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-rw-r--r--kernel/drivers/ntb/Kconfig13
-rw-r--r--kernel/drivers/ntb/Makefile3
-rw-r--r--kernel/drivers/ntb/ntb_hw.c1897
-rw-r--r--kernel/drivers/ntb/ntb_hw.h256
-rw-r--r--kernel/drivers/ntb/ntb_regs.h177
-rw-r--r--kernel/drivers/ntb/ntb_transport.c1776
6 files changed, 4122 insertions, 0 deletions
diff --git a/kernel/drivers/ntb/Kconfig b/kernel/drivers/ntb/Kconfig
new file mode 100644
index 000000000..f69df793d
--- /dev/null
+++ b/kernel/drivers/ntb/Kconfig
@@ -0,0 +1,13 @@
+config NTB
+ tristate "Intel Non-Transparent Bridge support"
+ depends on PCI
+ depends on X86
+ help
+ The PCI-E Non-transparent bridge hardware is a point-to-point PCI-E bus
+ connecting 2 systems. When configured, writes to the device's PCI
+ mapped memory will be mirrored to a buffer on the remote system. The
+ ntb Linux driver uses this point-to-point communication as a method to
+ transfer data from one system to the other.
+
+ If unsure, say N.
+
diff --git a/kernel/drivers/ntb/Makefile b/kernel/drivers/ntb/Makefile
new file mode 100644
index 000000000..15cb59fd3
--- /dev/null
+++ b/kernel/drivers/ntb/Makefile
@@ -0,0 +1,3 @@
+obj-$(CONFIG_NTB) += ntb.o
+
+ntb-objs := ntb_hw.o ntb_transport.o
diff --git a/kernel/drivers/ntb/ntb_hw.c b/kernel/drivers/ntb/ntb_hw.c
new file mode 100644
index 000000000..15f9b7c9e
--- /dev/null
+++ b/kernel/drivers/ntb/ntb_hw.c
@@ -0,0 +1,1897 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copy
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Intel PCIe NTB Linux driver
+ *
+ * Contact Information:
+ * Jon Mason <jon.mason@intel.com>
+ */
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include "ntb_hw.h"
+#include "ntb_regs.h"
+
+#define NTB_NAME "Intel(R) PCI-E Non-Transparent Bridge Driver"
+#define NTB_VER "1.0"
+
+MODULE_DESCRIPTION(NTB_NAME);
+MODULE_VERSION(NTB_VER);
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Intel Corporation");
+
+enum {
+ NTB_CONN_TRANSPARENT = 0,
+ NTB_CONN_B2B,
+ NTB_CONN_RP,
+};
+
+enum {
+ NTB_DEV_USD = 0,
+ NTB_DEV_DSD,
+};
+
+enum {
+ SNB_HW = 0,
+ BWD_HW,
+};
+
+static struct dentry *debugfs_dir;
+
+#define BWD_LINK_RECOVERY_TIME 500
+
+/* Translate memory window 0,1,2 to BAR 2,4,5 */
+#define MW_TO_BAR(mw) (mw == 0 ? 2 : (mw == 1 ? 4 : 5))
+
+static const struct pci_device_id ntb_pci_tbl[] = {
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_BWD)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_JSF)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_SNB)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_IVT)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_HSX)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_JSF)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_SNB)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_IVT)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_HSX)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_JSF)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_SNB)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_IVT)},
+ {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_HSX)},
+ {0}
+};
+MODULE_DEVICE_TABLE(pci, ntb_pci_tbl);
+
+static int is_ntb_xeon(struct ntb_device *ndev)
+{
+ switch (ndev->pdev->device) {
+ case PCI_DEVICE_ID_INTEL_NTB_SS_JSF:
+ case PCI_DEVICE_ID_INTEL_NTB_SS_SNB:
+ case PCI_DEVICE_ID_INTEL_NTB_SS_IVT:
+ case PCI_DEVICE_ID_INTEL_NTB_SS_HSX:
+ case PCI_DEVICE_ID_INTEL_NTB_PS_JSF:
+ case PCI_DEVICE_ID_INTEL_NTB_PS_SNB:
+ case PCI_DEVICE_ID_INTEL_NTB_PS_IVT:
+ case PCI_DEVICE_ID_INTEL_NTB_PS_HSX:
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_JSF:
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_SNB:
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_IVT:
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX:
+ return 1;
+ default:
+ return 0;
+ }
+
+ return 0;
+}
+
+static int is_ntb_atom(struct ntb_device *ndev)
+{
+ switch (ndev->pdev->device) {
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_BWD:
+ return 1;
+ default:
+ return 0;
+ }
+
+ return 0;
+}
+
+static void ntb_set_errata_flags(struct ntb_device *ndev)
+{
+ switch (ndev->pdev->device) {
+ /*
+ * this workaround applies to all platform up to IvyBridge
+ * Haswell has splitbar support and use a different workaround
+ */
+ case PCI_DEVICE_ID_INTEL_NTB_SS_JSF:
+ case PCI_DEVICE_ID_INTEL_NTB_SS_SNB:
+ case PCI_DEVICE_ID_INTEL_NTB_SS_IVT:
+ case PCI_DEVICE_ID_INTEL_NTB_SS_HSX:
+ case PCI_DEVICE_ID_INTEL_NTB_PS_JSF:
+ case PCI_DEVICE_ID_INTEL_NTB_PS_SNB:
+ case PCI_DEVICE_ID_INTEL_NTB_PS_IVT:
+ case PCI_DEVICE_ID_INTEL_NTB_PS_HSX:
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_JSF:
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_SNB:
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_IVT:
+ case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX:
+ ndev->wa_flags |= WA_SNB_ERR;
+ break;
+ }
+}
+
+/**
+ * ntb_register_event_callback() - register event callback
+ * @ndev: pointer to ntb_device instance
+ * @func: callback function to register
+ *
+ * This function registers a callback for any HW driver events such as link
+ * up/down, power management notices and etc.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_register_event_callback(struct ntb_device *ndev,
+ void (*func)(void *handle,
+ enum ntb_hw_event event))
+{
+ if (ndev->event_cb)
+ return -EINVAL;
+
+ ndev->event_cb = func;
+
+ return 0;
+}
+
+/**
+ * ntb_unregister_event_callback() - unregisters the event callback
+ * @ndev: pointer to ntb_device instance
+ *
+ * This function unregisters the existing callback from transport
+ */
+void ntb_unregister_event_callback(struct ntb_device *ndev)
+{
+ ndev->event_cb = NULL;
+}
+
+static void ntb_irq_work(unsigned long data)
+{
+ struct ntb_db_cb *db_cb = (struct ntb_db_cb *)data;
+ int rc;
+
+ rc = db_cb->callback(db_cb->data, db_cb->db_num);
+ if (rc)
+ tasklet_schedule(&db_cb->irq_work);
+ else {
+ struct ntb_device *ndev = db_cb->ndev;
+ unsigned long mask;
+
+ mask = readw(ndev->reg_ofs.ldb_mask);
+ clear_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+ writew(mask, ndev->reg_ofs.ldb_mask);
+ }
+}
+
+/**
+ * ntb_register_db_callback() - register a callback for doorbell interrupt
+ * @ndev: pointer to ntb_device instance
+ * @idx: doorbell index to register callback, zero based
+ * @data: pointer to be returned to caller with every callback
+ * @func: callback function to register
+ *
+ * This function registers a callback function for the doorbell interrupt
+ * on the primary side. The function will unmask the doorbell as well to
+ * allow interrupt.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx,
+ void *data, int (*func)(void *data, int db_num))
+{
+ unsigned long mask;
+
+ if (idx >= ndev->max_cbs || ndev->db_cb[idx].callback) {
+ dev_warn(&ndev->pdev->dev, "Invalid Index.\n");
+ return -EINVAL;
+ }
+
+ ndev->db_cb[idx].callback = func;
+ ndev->db_cb[idx].data = data;
+ ndev->db_cb[idx].ndev = ndev;
+
+ tasklet_init(&ndev->db_cb[idx].irq_work, ntb_irq_work,
+ (unsigned long) &ndev->db_cb[idx]);
+
+ /* unmask interrupt */
+ mask = readw(ndev->reg_ofs.ldb_mask);
+ clear_bit(idx * ndev->bits_per_vector, &mask);
+ writew(mask, ndev->reg_ofs.ldb_mask);
+
+ return 0;
+}
+
+/**
+ * ntb_unregister_db_callback() - unregister a callback for doorbell interrupt
+ * @ndev: pointer to ntb_device instance
+ * @idx: doorbell index to register callback, zero based
+ *
+ * This function unregisters a callback function for the doorbell interrupt
+ * on the primary side. The function will also mask the said doorbell.
+ */
+void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx)
+{
+ unsigned long mask;
+
+ if (idx >= ndev->max_cbs || !ndev->db_cb[idx].callback)
+ return;
+
+ mask = readw(ndev->reg_ofs.ldb_mask);
+ set_bit(idx * ndev->bits_per_vector, &mask);
+ writew(mask, ndev->reg_ofs.ldb_mask);
+
+ tasklet_disable(&ndev->db_cb[idx].irq_work);
+
+ ndev->db_cb[idx].callback = NULL;
+}
+
+/**
+ * ntb_find_transport() - find the transport pointer
+ * @transport: pointer to pci device
+ *
+ * Given the pci device pointer, return the transport pointer passed in when
+ * the transport attached when it was inited.
+ *
+ * RETURNS: pointer to transport.
+ */
+void *ntb_find_transport(struct pci_dev *pdev)
+{
+ struct ntb_device *ndev = pci_get_drvdata(pdev);
+ return ndev->ntb_transport;
+}
+
+/**
+ * ntb_register_transport() - Register NTB transport with NTB HW driver
+ * @transport: transport identifier
+ *
+ * This function allows a transport to reserve the hardware driver for
+ * NTB usage.
+ *
+ * RETURNS: pointer to ntb_device, NULL on error.
+ */
+struct ntb_device *ntb_register_transport(struct pci_dev *pdev, void *transport)
+{
+ struct ntb_device *ndev = pci_get_drvdata(pdev);
+
+ if (ndev->ntb_transport)
+ return NULL;
+
+ ndev->ntb_transport = transport;
+ return ndev;
+}
+
+/**
+ * ntb_unregister_transport() - Unregister the transport with the NTB HW driver
+ * @ndev - ntb_device of the transport to be freed
+ *
+ * This function unregisters the transport from the HW driver and performs any
+ * necessary cleanups.
+ */
+void ntb_unregister_transport(struct ntb_device *ndev)
+{
+ int i;
+
+ if (!ndev->ntb_transport)
+ return;
+
+ for (i = 0; i < ndev->max_cbs; i++)
+ ntb_unregister_db_callback(ndev, i);
+
+ ntb_unregister_event_callback(ndev);
+ ndev->ntb_transport = NULL;
+}
+
+/**
+ * ntb_write_local_spad() - write to the secondary scratchpad register
+ * @ndev: pointer to ntb_device instance
+ * @idx: index to the scratchpad register, 0 based
+ * @val: the data value to put into the register
+ *
+ * This function allows writing of a 32bit value to the indexed scratchpad
+ * register. This writes over the data mirrored to the local scratchpad register
+ * by the remote system.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_write_local_spad(struct ntb_device *ndev, unsigned int idx, u32 val)
+{
+ if (idx >= ndev->limits.max_spads)
+ return -EINVAL;
+
+ dev_dbg(&ndev->pdev->dev, "Writing %x to local scratch pad index %d\n",
+ val, idx);
+ writel(val, ndev->reg_ofs.spad_read + idx * 4);
+
+ return 0;
+}
+
+/**
+ * ntb_read_local_spad() - read from the primary scratchpad register
+ * @ndev: pointer to ntb_device instance
+ * @idx: index to scratchpad register, 0 based
+ * @val: pointer to 32bit integer for storing the register value
+ *
+ * This function allows reading of the 32bit scratchpad register on
+ * the primary (internal) side. This allows the local system to read data
+ * written and mirrored to the scratchpad register by the remote system.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_read_local_spad(struct ntb_device *ndev, unsigned int idx, u32 *val)
+{
+ if (idx >= ndev->limits.max_spads)
+ return -EINVAL;
+
+ *val = readl(ndev->reg_ofs.spad_write + idx * 4);
+ dev_dbg(&ndev->pdev->dev,
+ "Reading %x from local scratch pad index %d\n", *val, idx);
+
+ return 0;
+}
+
+/**
+ * ntb_write_remote_spad() - write to the secondary scratchpad register
+ * @ndev: pointer to ntb_device instance
+ * @idx: index to the scratchpad register, 0 based
+ * @val: the data value to put into the register
+ *
+ * This function allows writing of a 32bit value to the indexed scratchpad
+ * register. The register resides on the secondary (external) side. This allows
+ * the local system to write data to be mirrored to the remote systems
+ * scratchpad register.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_write_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 val)
+{
+ if (idx >= ndev->limits.max_spads)
+ return -EINVAL;
+
+ dev_dbg(&ndev->pdev->dev, "Writing %x to remote scratch pad index %d\n",
+ val, idx);
+ writel(val, ndev->reg_ofs.spad_write + idx * 4);
+
+ return 0;
+}
+
+/**
+ * ntb_read_remote_spad() - read from the primary scratchpad register
+ * @ndev: pointer to ntb_device instance
+ * @idx: index to scratchpad register, 0 based
+ * @val: pointer to 32bit integer for storing the register value
+ *
+ * This function allows reading of the 32bit scratchpad register on
+ * the primary (internal) side. This alloows the local system to read the data
+ * it wrote to be mirrored on the remote system.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_read_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 *val)
+{
+ if (idx >= ndev->limits.max_spads)
+ return -EINVAL;
+
+ *val = readl(ndev->reg_ofs.spad_read + idx * 4);
+ dev_dbg(&ndev->pdev->dev,
+ "Reading %x from remote scratch pad index %d\n", *val, idx);
+
+ return 0;
+}
+
+/**
+ * ntb_get_mw_base() - get addr for the NTB memory window
+ * @ndev: pointer to ntb_device instance
+ * @mw: memory window number
+ *
+ * This function provides the base address of the memory window specified.
+ *
+ * RETURNS: address, or NULL on error.
+ */
+resource_size_t ntb_get_mw_base(struct ntb_device *ndev, unsigned int mw)
+{
+ if (mw >= ntb_max_mw(ndev))
+ return 0;
+
+ return pci_resource_start(ndev->pdev, MW_TO_BAR(mw));
+}
+
+/**
+ * ntb_get_mw_vbase() - get virtual addr for the NTB memory window
+ * @ndev: pointer to ntb_device instance
+ * @mw: memory window number
+ *
+ * This function provides the base virtual address of the memory window
+ * specified.
+ *
+ * RETURNS: pointer to virtual address, or NULL on error.
+ */
+void __iomem *ntb_get_mw_vbase(struct ntb_device *ndev, unsigned int mw)
+{
+ if (mw >= ntb_max_mw(ndev))
+ return NULL;
+
+ return ndev->mw[mw].vbase;
+}
+
+/**
+ * ntb_get_mw_size() - return size of NTB memory window
+ * @ndev: pointer to ntb_device instance
+ * @mw: memory window number
+ *
+ * This function provides the physical size of the memory window specified
+ *
+ * RETURNS: the size of the memory window or zero on error
+ */
+u64 ntb_get_mw_size(struct ntb_device *ndev, unsigned int mw)
+{
+ if (mw >= ntb_max_mw(ndev))
+ return 0;
+
+ return ndev->mw[mw].bar_sz;
+}
+
+/**
+ * ntb_set_mw_addr - set the memory window address
+ * @ndev: pointer to ntb_device instance
+ * @mw: memory window number
+ * @addr: base address for data
+ *
+ * This function sets the base physical address of the memory window. This
+ * memory address is where data from the remote system will be transfered into
+ * or out of depending on how the transport is configured.
+ */
+void ntb_set_mw_addr(struct ntb_device *ndev, unsigned int mw, u64 addr)
+{
+ if (mw >= ntb_max_mw(ndev))
+ return;
+
+ dev_dbg(&ndev->pdev->dev, "Writing addr %Lx to BAR %d\n", addr,
+ MW_TO_BAR(mw));
+
+ ndev->mw[mw].phys_addr = addr;
+
+ switch (MW_TO_BAR(mw)) {
+ case NTB_BAR_23:
+ writeq(addr, ndev->reg_ofs.bar2_xlat);
+ break;
+ case NTB_BAR_4:
+ if (ndev->split_bar)
+ writel(addr, ndev->reg_ofs.bar4_xlat);
+ else
+ writeq(addr, ndev->reg_ofs.bar4_xlat);
+ break;
+ case NTB_BAR_5:
+ writel(addr, ndev->reg_ofs.bar5_xlat);
+ break;
+ }
+}
+
+/**
+ * ntb_ring_doorbell() - Set the doorbell on the secondary/external side
+ * @ndev: pointer to ntb_device instance
+ * @db: doorbell to ring
+ *
+ * This function allows triggering of a doorbell on the secondary/external
+ * side that will initiate an interrupt on the remote host
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+void ntb_ring_doorbell(struct ntb_device *ndev, unsigned int db)
+{
+ dev_dbg(&ndev->pdev->dev, "%s: ringing doorbell %d\n", __func__, db);
+
+ if (ndev->hw_type == BWD_HW)
+ writeq((u64) 1 << db, ndev->reg_ofs.rdb);
+ else
+ writew(((1 << ndev->bits_per_vector) - 1) <<
+ (db * ndev->bits_per_vector), ndev->reg_ofs.rdb);
+}
+
+static void bwd_recover_link(struct ntb_device *ndev)
+{
+ u32 status;
+
+ /* Driver resets the NTB ModPhy lanes - magic! */
+ writeb(0xe0, ndev->reg_base + BWD_MODPHY_PCSREG6);
+ writeb(0x40, ndev->reg_base + BWD_MODPHY_PCSREG4);
+ writeb(0x60, ndev->reg_base + BWD_MODPHY_PCSREG4);
+ writeb(0x60, ndev->reg_base + BWD_MODPHY_PCSREG6);
+
+ /* Driver waits 100ms to allow the NTB ModPhy to settle */
+ msleep(100);
+
+ /* Clear AER Errors, write to clear */
+ status = readl(ndev->reg_base + BWD_ERRCORSTS_OFFSET);
+ dev_dbg(&ndev->pdev->dev, "ERRCORSTS = %x\n", status);
+ status &= PCI_ERR_COR_REP_ROLL;
+ writel(status, ndev->reg_base + BWD_ERRCORSTS_OFFSET);
+
+ /* Clear unexpected electrical idle event in LTSSM, write to clear */
+ status = readl(ndev->reg_base + BWD_LTSSMERRSTS0_OFFSET);
+ dev_dbg(&ndev->pdev->dev, "LTSSMERRSTS0 = %x\n", status);
+ status |= BWD_LTSSMERRSTS0_UNEXPECTEDEI;
+ writel(status, ndev->reg_base + BWD_LTSSMERRSTS0_OFFSET);
+
+ /* Clear DeSkew Buffer error, write to clear */
+ status = readl(ndev->reg_base + BWD_DESKEWSTS_OFFSET);
+ dev_dbg(&ndev->pdev->dev, "DESKEWSTS = %x\n", status);
+ status |= BWD_DESKEWSTS_DBERR;
+ writel(status, ndev->reg_base + BWD_DESKEWSTS_OFFSET);
+
+ status = readl(ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET);
+ dev_dbg(&ndev->pdev->dev, "IBSTERRRCRVSTS0 = %x\n", status);
+ status &= BWD_IBIST_ERR_OFLOW;
+ writel(status, ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET);
+
+ /* Releases the NTB state machine to allow the link to retrain */
+ status = readl(ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET);
+ dev_dbg(&ndev->pdev->dev, "LTSSMSTATEJMP = %x\n", status);
+ status &= ~BWD_LTSSMSTATEJMP_FORCEDETECT;
+ writel(status, ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET);
+}
+
+static void ntb_link_event(struct ntb_device *ndev, int link_state)
+{
+ unsigned int event;
+
+ if (ndev->link_status == link_state)
+ return;
+
+ if (link_state == NTB_LINK_UP) {
+ u16 status;
+
+ dev_info(&ndev->pdev->dev, "Link Up\n");
+ ndev->link_status = NTB_LINK_UP;
+ event = NTB_EVENT_HW_LINK_UP;
+
+ if (is_ntb_atom(ndev) ||
+ ndev->conn_type == NTB_CONN_TRANSPARENT)
+ status = readw(ndev->reg_ofs.lnk_stat);
+ else {
+ int rc = pci_read_config_word(ndev->pdev,
+ SNB_LINK_STATUS_OFFSET,
+ &status);
+ if (rc)
+ return;
+ }
+
+ ndev->link_width = (status & NTB_LINK_WIDTH_MASK) >> 4;
+ ndev->link_speed = (status & NTB_LINK_SPEED_MASK);
+ dev_info(&ndev->pdev->dev, "Link Width %d, Link Speed %d\n",
+ ndev->link_width, ndev->link_speed);
+ } else {
+ dev_info(&ndev->pdev->dev, "Link Down\n");
+ ndev->link_status = NTB_LINK_DOWN;
+ event = NTB_EVENT_HW_LINK_DOWN;
+ /* Don't modify link width/speed, we need it in link recovery */
+ }
+
+ /* notify the upper layer if we have an event change */
+ if (ndev->event_cb)
+ ndev->event_cb(ndev->ntb_transport, event);
+}
+
+static int ntb_link_status(struct ntb_device *ndev)
+{
+ int link_state;
+
+ if (is_ntb_atom(ndev)) {
+ u32 ntb_cntl;
+
+ ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+ if (ntb_cntl & BWD_CNTL_LINK_DOWN)
+ link_state = NTB_LINK_DOWN;
+ else
+ link_state = NTB_LINK_UP;
+ } else {
+ u16 status;
+ int rc;
+
+ rc = pci_read_config_word(ndev->pdev, SNB_LINK_STATUS_OFFSET,
+ &status);
+ if (rc)
+ return rc;
+
+ if (status & NTB_LINK_STATUS_ACTIVE)
+ link_state = NTB_LINK_UP;
+ else
+ link_state = NTB_LINK_DOWN;
+ }
+
+ ntb_link_event(ndev, link_state);
+
+ return 0;
+}
+
+static void bwd_link_recovery(struct work_struct *work)
+{
+ struct ntb_device *ndev = container_of(work, struct ntb_device,
+ lr_timer.work);
+ u32 status32;
+
+ bwd_recover_link(ndev);
+ /* There is a potential race between the 2 NTB devices recovering at the
+ * same time. If the times are the same, the link will not recover and
+ * the driver will be stuck in this loop forever. Add a random interval
+ * to the recovery time to prevent this race.
+ */
+ msleep(BWD_LINK_RECOVERY_TIME + prandom_u32() % BWD_LINK_RECOVERY_TIME);
+
+ status32 = readl(ndev->reg_base + BWD_LTSSMSTATEJMP_OFFSET);
+ if (status32 & BWD_LTSSMSTATEJMP_FORCEDETECT)
+ goto retry;
+
+ status32 = readl(ndev->reg_base + BWD_IBSTERRRCRVSTS0_OFFSET);
+ if (status32 & BWD_IBIST_ERR_OFLOW)
+ goto retry;
+
+ status32 = readl(ndev->reg_ofs.lnk_cntl);
+ if (!(status32 & BWD_CNTL_LINK_DOWN)) {
+ unsigned char speed, width;
+ u16 status16;
+
+ status16 = readw(ndev->reg_ofs.lnk_stat);
+ width = (status16 & NTB_LINK_WIDTH_MASK) >> 4;
+ speed = (status16 & NTB_LINK_SPEED_MASK);
+ if (ndev->link_width != width || ndev->link_speed != speed)
+ goto retry;
+ }
+
+ schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT);
+ return;
+
+retry:
+ schedule_delayed_work(&ndev->lr_timer, NTB_HB_TIMEOUT);
+}
+
+/* BWD doesn't have link status interrupt, poll on that platform */
+static void bwd_link_poll(struct work_struct *work)
+{
+ struct ntb_device *ndev = container_of(work, struct ntb_device,
+ hb_timer.work);
+ unsigned long ts = jiffies;
+
+ /* If we haven't gotten an interrupt in a while, check the BWD link
+ * status bit
+ */
+ if (ts > ndev->last_ts + NTB_HB_TIMEOUT) {
+ int rc = ntb_link_status(ndev);
+ if (rc)
+ dev_err(&ndev->pdev->dev,
+ "Error determining link status\n");
+
+ /* Check to see if a link error is the cause of the link down */
+ if (ndev->link_status == NTB_LINK_DOWN) {
+ u32 status32 = readl(ndev->reg_base +
+ BWD_LTSSMSTATEJMP_OFFSET);
+ if (status32 & BWD_LTSSMSTATEJMP_FORCEDETECT) {
+ schedule_delayed_work(&ndev->lr_timer, 0);
+ return;
+ }
+ }
+ }
+
+ schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT);
+}
+
+static int ntb_xeon_setup(struct ntb_device *ndev)
+{
+ switch (ndev->conn_type) {
+ case NTB_CONN_B2B:
+ ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET;
+ ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET;
+ ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET;
+ ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET;
+ ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET;
+ if (ndev->split_bar)
+ ndev->reg_ofs.bar5_xlat =
+ ndev->reg_base + SNB_SBAR5XLAT_OFFSET;
+ ndev->limits.max_spads = SNB_MAX_B2B_SPADS;
+
+ /* There is a Xeon hardware errata related to writes to
+ * SDOORBELL or B2BDOORBELL in conjunction with inbound access
+ * to NTB MMIO Space, which may hang the system. To workaround
+ * this use the second memory window to access the interrupt and
+ * scratch pad registers on the remote system.
+ */
+ if (ndev->wa_flags & WA_SNB_ERR) {
+ if (!ndev->mw[ndev->limits.max_mw - 1].bar_sz)
+ return -EINVAL;
+
+ ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
+ ndev->reg_ofs.spad_write =
+ ndev->mw[ndev->limits.max_mw - 1].vbase +
+ SNB_SPAD_OFFSET;
+ ndev->reg_ofs.rdb =
+ ndev->mw[ndev->limits.max_mw - 1].vbase +
+ SNB_PDOORBELL_OFFSET;
+
+ /* Set the Limit register to 4k, the minimum size, to
+ * prevent an illegal access
+ */
+ writeq(ndev->mw[1].bar_sz + 0x1000, ndev->reg_base +
+ SNB_PBAR4LMT_OFFSET);
+ /* HW errata on the Limit registers. They can only be
+ * written when the base register is 4GB aligned and
+ * < 32bit. This should already be the case based on
+ * the driver defaults, but write the Limit registers
+ * first just in case.
+ */
+
+ ndev->limits.max_mw = SNB_ERRATA_MAX_MW;
+ } else {
+ /* HW Errata on bit 14 of b2bdoorbell register. Writes
+ * will not be mirrored to the remote system. Shrink
+ * the number of bits by one, since bit 14 is the last
+ * bit.
+ */
+ ndev->limits.max_db_bits = SNB_MAX_DB_BITS - 1;
+ ndev->reg_ofs.spad_write = ndev->reg_base +
+ SNB_B2B_SPAD_OFFSET;
+ ndev->reg_ofs.rdb = ndev->reg_base +
+ SNB_B2B_DOORBELL_OFFSET;
+
+ /* Disable the Limit register, just incase it is set to
+ * something silly. A 64bit write should handle it
+ * regardless of whether it has a split BAR or not.
+ */
+ writeq(0, ndev->reg_base + SNB_PBAR4LMT_OFFSET);
+ /* HW errata on the Limit registers. They can only be
+ * written when the base register is 4GB aligned and
+ * < 32bit. This should already be the case based on
+ * the driver defaults, but write the Limit registers
+ * first just in case.
+ */
+ if (ndev->split_bar)
+ ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
+ else
+ ndev->limits.max_mw = SNB_MAX_MW;
+ }
+
+ /* The Xeon errata workaround requires setting SBAR Base
+ * addresses to known values, so that the PBAR XLAT can be
+ * pointed at SBAR0 of the remote system.
+ */
+ if (ndev->dev_type == NTB_DEV_USD) {
+ writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base +
+ SNB_PBAR2XLAT_OFFSET);
+ if (ndev->wa_flags & WA_SNB_ERR)
+ writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base +
+ SNB_PBAR4XLAT_OFFSET);
+ else {
+ if (ndev->split_bar) {
+ writel(SNB_MBAR4_DSD_ADDR,
+ ndev->reg_base +
+ SNB_PBAR4XLAT_OFFSET);
+ writel(SNB_MBAR5_DSD_ADDR,
+ ndev->reg_base +
+ SNB_PBAR5XLAT_OFFSET);
+ } else
+ writeq(SNB_MBAR4_DSD_ADDR,
+ ndev->reg_base +
+ SNB_PBAR4XLAT_OFFSET);
+
+ /* B2B_XLAT_OFFSET is a 64bit register, but can
+ * only take 32bit writes
+ */
+ writel(SNB_MBAR01_DSD_ADDR & 0xffffffff,
+ ndev->reg_base + SNB_B2B_XLAT_OFFSETL);
+ writel(SNB_MBAR01_DSD_ADDR >> 32,
+ ndev->reg_base + SNB_B2B_XLAT_OFFSETU);
+ }
+
+ writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base +
+ SNB_SBAR0BASE_OFFSET);
+ writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base +
+ SNB_SBAR2BASE_OFFSET);
+ if (ndev->split_bar) {
+ writel(SNB_MBAR4_USD_ADDR, ndev->reg_base +
+ SNB_SBAR4BASE_OFFSET);
+ writel(SNB_MBAR5_USD_ADDR, ndev->reg_base +
+ SNB_SBAR5BASE_OFFSET);
+ } else
+ writeq(SNB_MBAR4_USD_ADDR, ndev->reg_base +
+ SNB_SBAR4BASE_OFFSET);
+ } else {
+ writeq(SNB_MBAR23_USD_ADDR, ndev->reg_base +
+ SNB_PBAR2XLAT_OFFSET);
+ if (ndev->wa_flags & WA_SNB_ERR)
+ writeq(SNB_MBAR01_USD_ADDR, ndev->reg_base +
+ SNB_PBAR4XLAT_OFFSET);
+ else {
+ if (ndev->split_bar) {
+ writel(SNB_MBAR4_USD_ADDR,
+ ndev->reg_base +
+ SNB_PBAR4XLAT_OFFSET);
+ writel(SNB_MBAR5_USD_ADDR,
+ ndev->reg_base +
+ SNB_PBAR5XLAT_OFFSET);
+ } else
+ writeq(SNB_MBAR4_USD_ADDR,
+ ndev->reg_base +
+ SNB_PBAR4XLAT_OFFSET);
+
+ /*
+ * B2B_XLAT_OFFSET is a 64bit register, but can
+ * only take 32bit writes
+ */
+ writel(SNB_MBAR01_USD_ADDR & 0xffffffff,
+ ndev->reg_base + SNB_B2B_XLAT_OFFSETL);
+ writel(SNB_MBAR01_USD_ADDR >> 32,
+ ndev->reg_base + SNB_B2B_XLAT_OFFSETU);
+ }
+ writeq(SNB_MBAR01_DSD_ADDR, ndev->reg_base +
+ SNB_SBAR0BASE_OFFSET);
+ writeq(SNB_MBAR23_DSD_ADDR, ndev->reg_base +
+ SNB_SBAR2BASE_OFFSET);
+ if (ndev->split_bar) {
+ writel(SNB_MBAR4_DSD_ADDR, ndev->reg_base +
+ SNB_SBAR4BASE_OFFSET);
+ writel(SNB_MBAR5_DSD_ADDR, ndev->reg_base +
+ SNB_SBAR5BASE_OFFSET);
+ } else
+ writeq(SNB_MBAR4_DSD_ADDR, ndev->reg_base +
+ SNB_SBAR4BASE_OFFSET);
+
+ }
+ break;
+ case NTB_CONN_RP:
+ if (ndev->wa_flags & WA_SNB_ERR) {
+ dev_err(&ndev->pdev->dev,
+ "NTB-RP disabled due to hardware errata.\n");
+ return -EINVAL;
+ }
+
+ /* Scratch pads need to have exclusive access from the primary
+ * or secondary side. Halve the num spads so that each side can
+ * have an equal amount.
+ */
+ ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2;
+ ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
+ /* Note: The SDOORBELL is the cause of the errata. You REALLY
+ * don't want to touch it.
+ */
+ ndev->reg_ofs.rdb = ndev->reg_base + SNB_SDOORBELL_OFFSET;
+ ndev->reg_ofs.ldb = ndev->reg_base + SNB_PDOORBELL_OFFSET;
+ ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_PDBMSK_OFFSET;
+ /* Offset the start of the spads to correspond to whether it is
+ * primary or secondary
+ */
+ ndev->reg_ofs.spad_write = ndev->reg_base + SNB_SPAD_OFFSET +
+ ndev->limits.max_spads * 4;
+ ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET;
+ ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_SBAR2XLAT_OFFSET;
+ ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_SBAR4XLAT_OFFSET;
+ if (ndev->split_bar) {
+ ndev->reg_ofs.bar5_xlat =
+ ndev->reg_base + SNB_SBAR5XLAT_OFFSET;
+ ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
+ } else
+ ndev->limits.max_mw = SNB_MAX_MW;
+ break;
+ case NTB_CONN_TRANSPARENT:
+ if (ndev->wa_flags & WA_SNB_ERR) {
+ dev_err(&ndev->pdev->dev,
+ "NTB-TRANSPARENT disabled due to hardware errata.\n");
+ return -EINVAL;
+ }
+
+ /* Scratch pads need to have exclusive access from the primary
+ * or secondary side. Halve the num spads so that each side can
+ * have an equal amount.
+ */
+ ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2;
+ ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
+ ndev->reg_ofs.rdb = ndev->reg_base + SNB_PDOORBELL_OFFSET;
+ ndev->reg_ofs.ldb = ndev->reg_base + SNB_SDOORBELL_OFFSET;
+ ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_SDBMSK_OFFSET;
+ ndev->reg_ofs.spad_write = ndev->reg_base + SNB_SPAD_OFFSET;
+ /* Offset the start of the spads to correspond to whether it is
+ * primary or secondary
+ */
+ ndev->reg_ofs.spad_read = ndev->reg_base + SNB_SPAD_OFFSET +
+ ndev->limits.max_spads * 4;
+ ndev->reg_ofs.bar2_xlat = ndev->reg_base + SNB_PBAR2XLAT_OFFSET;
+ ndev->reg_ofs.bar4_xlat = ndev->reg_base + SNB_PBAR4XLAT_OFFSET;
+
+ if (ndev->split_bar) {
+ ndev->reg_ofs.bar5_xlat =
+ ndev->reg_base + SNB_PBAR5XLAT_OFFSET;
+ ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
+ } else
+ ndev->limits.max_mw = SNB_MAX_MW;
+ break;
+ default:
+ /*
+ * we should never hit this. the detect function should've
+ * take cared of everything.
+ */
+ return -EINVAL;
+ }
+
+ ndev->reg_ofs.lnk_cntl = ndev->reg_base + SNB_NTBCNTL_OFFSET;
+ ndev->reg_ofs.lnk_stat = ndev->reg_base + SNB_SLINK_STATUS_OFFSET;
+ ndev->reg_ofs.spci_cmd = ndev->reg_base + SNB_PCICMD_OFFSET;
+
+ ndev->limits.msix_cnt = SNB_MSIX_CNT;
+ ndev->bits_per_vector = SNB_DB_BITS_PER_VEC;
+
+ return 0;
+}
+
+static int ntb_bwd_setup(struct ntb_device *ndev)
+{
+ int rc;
+ u32 val;
+
+ ndev->hw_type = BWD_HW;
+
+ rc = pci_read_config_dword(ndev->pdev, NTB_PPD_OFFSET, &val);
+ if (rc)
+ return rc;
+
+ switch ((val & BWD_PPD_CONN_TYPE) >> 8) {
+ case NTB_CONN_B2B:
+ ndev->conn_type = NTB_CONN_B2B;
+ break;
+ case NTB_CONN_RP:
+ default:
+ dev_err(&ndev->pdev->dev, "Unsupported NTB configuration\n");
+ return -EINVAL;
+ }
+
+ if (val & BWD_PPD_DEV_TYPE)
+ ndev->dev_type = NTB_DEV_DSD;
+ else
+ ndev->dev_type = NTB_DEV_USD;
+
+ /* Initiate PCI-E link training */
+ rc = pci_write_config_dword(ndev->pdev, NTB_PPD_OFFSET,
+ val | BWD_PPD_INIT_LINK);
+ if (rc)
+ return rc;
+
+ ndev->reg_ofs.ldb = ndev->reg_base + BWD_PDOORBELL_OFFSET;
+ ndev->reg_ofs.ldb_mask = ndev->reg_base + BWD_PDBMSK_OFFSET;
+ ndev->reg_ofs.rdb = ndev->reg_base + BWD_B2B_DOORBELL_OFFSET;
+ ndev->reg_ofs.bar2_xlat = ndev->reg_base + BWD_SBAR2XLAT_OFFSET;
+ ndev->reg_ofs.bar4_xlat = ndev->reg_base + BWD_SBAR4XLAT_OFFSET;
+ ndev->reg_ofs.lnk_cntl = ndev->reg_base + BWD_NTBCNTL_OFFSET;
+ ndev->reg_ofs.lnk_stat = ndev->reg_base + BWD_LINK_STATUS_OFFSET;
+ ndev->reg_ofs.spad_read = ndev->reg_base + BWD_SPAD_OFFSET;
+ ndev->reg_ofs.spad_write = ndev->reg_base + BWD_B2B_SPAD_OFFSET;
+ ndev->reg_ofs.spci_cmd = ndev->reg_base + BWD_PCICMD_OFFSET;
+ ndev->limits.max_mw = BWD_MAX_MW;
+ ndev->limits.max_spads = BWD_MAX_SPADS;
+ ndev->limits.max_db_bits = BWD_MAX_DB_BITS;
+ ndev->limits.msix_cnt = BWD_MSIX_CNT;
+ ndev->bits_per_vector = BWD_DB_BITS_PER_VEC;
+
+ /* Since bwd doesn't have a link interrupt, setup a poll timer */
+ INIT_DELAYED_WORK(&ndev->hb_timer, bwd_link_poll);
+ INIT_DELAYED_WORK(&ndev->lr_timer, bwd_link_recovery);
+ schedule_delayed_work(&ndev->hb_timer, NTB_HB_TIMEOUT);
+
+ return 0;
+}
+
+static int ntb_device_setup(struct ntb_device *ndev)
+{
+ int rc;
+
+ if (is_ntb_xeon(ndev))
+ rc = ntb_xeon_setup(ndev);
+ else if (is_ntb_atom(ndev))
+ rc = ntb_bwd_setup(ndev);
+ else
+ rc = -ENODEV;
+
+ if (rc)
+ return rc;
+
+ if (ndev->conn_type == NTB_CONN_B2B)
+ /* Enable Bus Master and Memory Space on the secondary side */
+ writew(PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER,
+ ndev->reg_ofs.spci_cmd);
+
+ return 0;
+}
+
+static void ntb_device_free(struct ntb_device *ndev)
+{
+ if (is_ntb_atom(ndev)) {
+ cancel_delayed_work_sync(&ndev->hb_timer);
+ cancel_delayed_work_sync(&ndev->lr_timer);
+ }
+}
+
+static irqreturn_t bwd_callback_msix_irq(int irq, void *data)
+{
+ struct ntb_db_cb *db_cb = data;
+ struct ntb_device *ndev = db_cb->ndev;
+ unsigned long mask;
+
+ dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq,
+ db_cb->db_num);
+
+ mask = readw(ndev->reg_ofs.ldb_mask);
+ set_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+ writew(mask, ndev->reg_ofs.ldb_mask);
+
+ tasklet_schedule(&db_cb->irq_work);
+
+ /* No need to check for the specific HB irq, any interrupt means
+ * we're connected.
+ */
+ ndev->last_ts = jiffies;
+
+ writeq((u64) 1 << db_cb->db_num, ndev->reg_ofs.ldb);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t xeon_callback_msix_irq(int irq, void *data)
+{
+ struct ntb_db_cb *db_cb = data;
+ struct ntb_device *ndev = db_cb->ndev;
+ unsigned long mask;
+
+ dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq,
+ db_cb->db_num);
+
+ mask = readw(ndev->reg_ofs.ldb_mask);
+ set_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+ writew(mask, ndev->reg_ofs.ldb_mask);
+
+ tasklet_schedule(&db_cb->irq_work);
+
+ /* On Sandybridge, there are 16 bits in the interrupt register
+ * but only 4 vectors. So, 5 bits are assigned to the first 3
+ * vectors, with the 4th having a single bit for link
+ * interrupts.
+ */
+ writew(((1 << ndev->bits_per_vector) - 1) <<
+ (db_cb->db_num * ndev->bits_per_vector), ndev->reg_ofs.ldb);
+
+ return IRQ_HANDLED;
+}
+
+/* Since we do not have a HW doorbell in BWD, this is only used in JF/JT */
+static irqreturn_t xeon_event_msix_irq(int irq, void *dev)
+{
+ struct ntb_device *ndev = dev;
+ int rc;
+
+ dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for Events\n", irq);
+
+ rc = ntb_link_status(ndev);
+ if (rc)
+ dev_err(&ndev->pdev->dev, "Error determining link status\n");
+
+ /* bit 15 is always the link bit */
+ writew(1 << SNB_LINK_DB, ndev->reg_ofs.ldb);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t ntb_interrupt(int irq, void *dev)
+{
+ struct ntb_device *ndev = dev;
+ unsigned int i = 0;
+
+ if (is_ntb_atom(ndev)) {
+ u64 ldb = readq(ndev->reg_ofs.ldb);
+
+ dev_dbg(&ndev->pdev->dev, "irq %d - ldb = %Lx\n", irq, ldb);
+
+ while (ldb) {
+ i = __ffs(ldb);
+ ldb &= ldb - 1;
+ bwd_callback_msix_irq(irq, &ndev->db_cb[i]);
+ }
+ } else {
+ u16 ldb = readw(ndev->reg_ofs.ldb);
+
+ dev_dbg(&ndev->pdev->dev, "irq %d - ldb = %x\n", irq, ldb);
+
+ if (ldb & SNB_DB_HW_LINK) {
+ xeon_event_msix_irq(irq, dev);
+ ldb &= ~SNB_DB_HW_LINK;
+ }
+
+ while (ldb) {
+ i = __ffs(ldb);
+ ldb &= ldb - 1;
+ xeon_callback_msix_irq(irq, &ndev->db_cb[i]);
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int ntb_setup_snb_msix(struct ntb_device *ndev, int msix_entries)
+{
+ struct pci_dev *pdev = ndev->pdev;
+ struct msix_entry *msix;
+ int rc, i;
+
+ if (msix_entries < ndev->limits.msix_cnt)
+ return -ENOSPC;
+
+ rc = pci_enable_msix_exact(pdev, ndev->msix_entries, msix_entries);
+ if (rc < 0)
+ return rc;
+
+ for (i = 0; i < msix_entries; i++) {
+ msix = &ndev->msix_entries[i];
+ WARN_ON(!msix->vector);
+
+ if (i == msix_entries - 1) {
+ rc = request_irq(msix->vector,
+ xeon_event_msix_irq, 0,
+ "ntb-event-msix", ndev);
+ if (rc)
+ goto err;
+ } else {
+ rc = request_irq(msix->vector,
+ xeon_callback_msix_irq, 0,
+ "ntb-callback-msix",
+ &ndev->db_cb[i]);
+ if (rc)
+ goto err;
+ }
+ }
+
+ ndev->num_msix = msix_entries;
+ ndev->max_cbs = msix_entries - 1;
+
+ return 0;
+
+err:
+ while (--i >= 0) {
+ /* Code never reaches here for entry nr 'ndev->num_msix - 1' */
+ msix = &ndev->msix_entries[i];
+ free_irq(msix->vector, &ndev->db_cb[i]);
+ }
+
+ pci_disable_msix(pdev);
+ ndev->num_msix = 0;
+
+ return rc;
+}
+
+static int ntb_setup_bwd_msix(struct ntb_device *ndev, int msix_entries)
+{
+ struct pci_dev *pdev = ndev->pdev;
+ struct msix_entry *msix;
+ int rc, i;
+
+ msix_entries = pci_enable_msix_range(pdev, ndev->msix_entries,
+ 1, msix_entries);
+ if (msix_entries < 0)
+ return msix_entries;
+
+ for (i = 0; i < msix_entries; i++) {
+ msix = &ndev->msix_entries[i];
+ WARN_ON(!msix->vector);
+
+ rc = request_irq(msix->vector, bwd_callback_msix_irq, 0,
+ "ntb-callback-msix", &ndev->db_cb[i]);
+ if (rc)
+ goto err;
+ }
+
+ ndev->num_msix = msix_entries;
+ ndev->max_cbs = msix_entries;
+
+ return 0;
+
+err:
+ while (--i >= 0)
+ free_irq(msix->vector, &ndev->db_cb[i]);
+
+ pci_disable_msix(pdev);
+ ndev->num_msix = 0;
+
+ return rc;
+}
+
+static int ntb_setup_msix(struct ntb_device *ndev)
+{
+ struct pci_dev *pdev = ndev->pdev;
+ int msix_entries;
+ int rc, i;
+
+ msix_entries = pci_msix_vec_count(pdev);
+ if (msix_entries < 0) {
+ rc = msix_entries;
+ goto err;
+ } else if (msix_entries > ndev->limits.msix_cnt) {
+ rc = -EINVAL;
+ goto err;
+ }
+
+ ndev->msix_entries = kmalloc(sizeof(struct msix_entry) * msix_entries,
+ GFP_KERNEL);
+ if (!ndev->msix_entries) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ for (i = 0; i < msix_entries; i++)
+ ndev->msix_entries[i].entry = i;
+
+ if (is_ntb_atom(ndev))
+ rc = ntb_setup_bwd_msix(ndev, msix_entries);
+ else
+ rc = ntb_setup_snb_msix(ndev, msix_entries);
+ if (rc)
+ goto err1;
+
+ return 0;
+
+err1:
+ kfree(ndev->msix_entries);
+err:
+ dev_err(&pdev->dev, "Error allocating MSI-X interrupt\n");
+ return rc;
+}
+
+static int ntb_setup_msi(struct ntb_device *ndev)
+{
+ struct pci_dev *pdev = ndev->pdev;
+ int rc;
+
+ rc = pci_enable_msi(pdev);
+ if (rc)
+ return rc;
+
+ rc = request_irq(pdev->irq, ntb_interrupt, 0, "ntb-msi", ndev);
+ if (rc) {
+ pci_disable_msi(pdev);
+ dev_err(&pdev->dev, "Error allocating MSI interrupt\n");
+ return rc;
+ }
+
+ return 0;
+}
+
+static int ntb_setup_intx(struct ntb_device *ndev)
+{
+ struct pci_dev *pdev = ndev->pdev;
+ int rc;
+
+ pci_msi_off(pdev);
+
+ /* Verify intx is enabled */
+ pci_intx(pdev, 1);
+
+ rc = request_irq(pdev->irq, ntb_interrupt, IRQF_SHARED, "ntb-intx",
+ ndev);
+ if (rc)
+ return rc;
+
+ return 0;
+}
+
+static int ntb_setup_interrupts(struct ntb_device *ndev)
+{
+ int rc;
+
+ /* On BWD, disable all interrupts. On SNB, disable all but Link
+ * Interrupt. The rest will be unmasked as callbacks are registered.
+ */
+ if (is_ntb_atom(ndev))
+ writeq(~0, ndev->reg_ofs.ldb_mask);
+ else {
+ u16 var = 1 << SNB_LINK_DB;
+ writew(~var, ndev->reg_ofs.ldb_mask);
+ }
+
+ rc = ntb_setup_msix(ndev);
+ if (!rc)
+ goto done;
+
+ ndev->bits_per_vector = 1;
+ ndev->max_cbs = ndev->limits.max_db_bits;
+
+ rc = ntb_setup_msi(ndev);
+ if (!rc)
+ goto done;
+
+ rc = ntb_setup_intx(ndev);
+ if (rc) {
+ dev_err(&ndev->pdev->dev, "no usable interrupts\n");
+ return rc;
+ }
+
+done:
+ return 0;
+}
+
+static void ntb_free_interrupts(struct ntb_device *ndev)
+{
+ struct pci_dev *pdev = ndev->pdev;
+
+ /* mask interrupts */
+ if (is_ntb_atom(ndev))
+ writeq(~0, ndev->reg_ofs.ldb_mask);
+ else
+ writew(~0, ndev->reg_ofs.ldb_mask);
+
+ if (ndev->num_msix) {
+ struct msix_entry *msix;
+ u32 i;
+
+ for (i = 0; i < ndev->num_msix; i++) {
+ msix = &ndev->msix_entries[i];
+ if (is_ntb_xeon(ndev) && i == ndev->num_msix - 1)
+ free_irq(msix->vector, ndev);
+ else
+ free_irq(msix->vector, &ndev->db_cb[i]);
+ }
+ pci_disable_msix(pdev);
+ kfree(ndev->msix_entries);
+ } else {
+ free_irq(pdev->irq, ndev);
+
+ if (pci_dev_msi_enabled(pdev))
+ pci_disable_msi(pdev);
+ }
+}
+
+static int ntb_create_callbacks(struct ntb_device *ndev)
+{
+ int i;
+
+ /* Chicken-egg issue. We won't know how many callbacks are necessary
+ * until we see how many MSI-X vectors we get, but these pointers need
+ * to be passed into the MSI-X register function. So, we allocate the
+ * max, knowing that they might not all be used, to work around this.
+ */
+ ndev->db_cb = kcalloc(ndev->limits.max_db_bits,
+ sizeof(struct ntb_db_cb),
+ GFP_KERNEL);
+ if (!ndev->db_cb)
+ return -ENOMEM;
+
+ for (i = 0; i < ndev->limits.max_db_bits; i++) {
+ ndev->db_cb[i].db_num = i;
+ ndev->db_cb[i].ndev = ndev;
+ }
+
+ return 0;
+}
+
+static void ntb_free_callbacks(struct ntb_device *ndev)
+{
+ int i;
+
+ for (i = 0; i < ndev->limits.max_db_bits; i++)
+ ntb_unregister_db_callback(ndev, i);
+
+ kfree(ndev->db_cb);
+}
+
+static ssize_t ntb_debugfs_read(struct file *filp, char __user *ubuf,
+ size_t count, loff_t *offp)
+{
+ struct ntb_device *ndev;
+ char *buf;
+ ssize_t ret, offset, out_count;
+
+ out_count = 500;
+
+ buf = kmalloc(out_count, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ndev = filp->private_data;
+ offset = 0;
+ offset += snprintf(buf + offset, out_count - offset,
+ "NTB Device Information:\n");
+ offset += snprintf(buf + offset, out_count - offset,
+ "Connection Type - \t\t%s\n",
+ ndev->conn_type == NTB_CONN_TRANSPARENT ?
+ "Transparent" : (ndev->conn_type == NTB_CONN_B2B) ?
+ "Back to back" : "Root Port");
+ offset += snprintf(buf + offset, out_count - offset,
+ "Device Type - \t\t\t%s\n",
+ ndev->dev_type == NTB_DEV_USD ?
+ "DSD/USP" : "USD/DSP");
+ offset += snprintf(buf + offset, out_count - offset,
+ "Max Number of Callbacks - \t%u\n",
+ ntb_max_cbs(ndev));
+ offset += snprintf(buf + offset, out_count - offset,
+ "Link Status - \t\t\t%s\n",
+ ntb_hw_link_status(ndev) ? "Up" : "Down");
+ if (ntb_hw_link_status(ndev)) {
+ offset += snprintf(buf + offset, out_count - offset,
+ "Link Speed - \t\t\tPCI-E Gen %u\n",
+ ndev->link_speed);
+ offset += snprintf(buf + offset, out_count - offset,
+ "Link Width - \t\t\tx%u\n",
+ ndev->link_width);
+ }
+
+ if (is_ntb_xeon(ndev)) {
+ u32 status32;
+ u16 status16;
+ int rc;
+
+ offset += snprintf(buf + offset, out_count - offset,
+ "\nNTB Device Statistics:\n");
+ offset += snprintf(buf + offset, out_count - offset,
+ "Upstream Memory Miss - \t%u\n",
+ readw(ndev->reg_base +
+ SNB_USMEMMISS_OFFSET));
+
+ offset += snprintf(buf + offset, out_count - offset,
+ "\nNTB Hardware Errors:\n");
+
+ rc = pci_read_config_word(ndev->pdev, SNB_DEVSTS_OFFSET,
+ &status16);
+ if (!rc)
+ offset += snprintf(buf + offset, out_count - offset,
+ "DEVSTS - \t%#06x\n", status16);
+
+ rc = pci_read_config_word(ndev->pdev, SNB_LINK_STATUS_OFFSET,
+ &status16);
+ if (!rc)
+ offset += snprintf(buf + offset, out_count - offset,
+ "LNKSTS - \t%#06x\n", status16);
+
+ rc = pci_read_config_dword(ndev->pdev, SNB_UNCERRSTS_OFFSET,
+ &status32);
+ if (!rc)
+ offset += snprintf(buf + offset, out_count - offset,
+ "UNCERRSTS - \t%#010x\n", status32);
+
+ rc = pci_read_config_dword(ndev->pdev, SNB_CORERRSTS_OFFSET,
+ &status32);
+ if (!rc)
+ offset += snprintf(buf + offset, out_count - offset,
+ "CORERRSTS - \t%#010x\n", status32);
+ }
+
+ if (offset > out_count)
+ offset = out_count;
+
+ ret = simple_read_from_buffer(ubuf, count, offp, buf, offset);
+ kfree(buf);
+ return ret;
+}
+
+static const struct file_operations ntb_debugfs_info = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = ntb_debugfs_read,
+};
+
+static void ntb_setup_debugfs(struct ntb_device *ndev)
+{
+ if (!debugfs_initialized())
+ return;
+
+ if (!debugfs_dir)
+ debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+
+ ndev->debugfs_dir = debugfs_create_dir(pci_name(ndev->pdev),
+ debugfs_dir);
+ if (ndev->debugfs_dir)
+ ndev->debugfs_info = debugfs_create_file("info", S_IRUSR,
+ ndev->debugfs_dir,
+ ndev,
+ &ntb_debugfs_info);
+}
+
+static void ntb_free_debugfs(struct ntb_device *ndev)
+{
+ debugfs_remove_recursive(ndev->debugfs_dir);
+
+ if (debugfs_dir && simple_empty(debugfs_dir)) {
+ debugfs_remove_recursive(debugfs_dir);
+ debugfs_dir = NULL;
+ }
+}
+
+static void ntb_hw_link_up(struct ntb_device *ndev)
+{
+ if (ndev->conn_type == NTB_CONN_TRANSPARENT)
+ ntb_link_event(ndev, NTB_LINK_UP);
+ else {
+ u32 ntb_cntl;
+
+ /* Let's bring the NTB link up */
+ ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+ ntb_cntl &= ~(NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK);
+ ntb_cntl |= NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP;
+ ntb_cntl |= NTB_CNTL_P2S_BAR4_SNOOP | NTB_CNTL_S2P_BAR4_SNOOP;
+ if (ndev->split_bar)
+ ntb_cntl |= NTB_CNTL_P2S_BAR5_SNOOP |
+ NTB_CNTL_S2P_BAR5_SNOOP;
+
+ writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+ }
+}
+
+static void ntb_hw_link_down(struct ntb_device *ndev)
+{
+ u32 ntb_cntl;
+
+ if (ndev->conn_type == NTB_CONN_TRANSPARENT) {
+ ntb_link_event(ndev, NTB_LINK_DOWN);
+ return;
+ }
+
+ /* Bring NTB link down */
+ ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+ ntb_cntl &= ~(NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP);
+ ntb_cntl &= ~(NTB_CNTL_P2S_BAR4_SNOOP | NTB_CNTL_S2P_BAR4_SNOOP);
+ if (ndev->split_bar)
+ ntb_cntl &= ~(NTB_CNTL_P2S_BAR5_SNOOP |
+ NTB_CNTL_S2P_BAR5_SNOOP);
+ ntb_cntl |= NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK;
+ writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+}
+
+static void ntb_max_mw_detect(struct ntb_device *ndev)
+{
+ if (ndev->split_bar)
+ ndev->limits.max_mw = HSX_SPLITBAR_MAX_MW;
+ else
+ ndev->limits.max_mw = SNB_MAX_MW;
+}
+
+static int ntb_xeon_detect(struct ntb_device *ndev)
+{
+ int rc, bars_mask;
+ u32 bars;
+ u8 ppd;
+
+ ndev->hw_type = SNB_HW;
+
+ rc = pci_read_config_byte(ndev->pdev, NTB_PPD_OFFSET, &ppd);
+ if (rc)
+ return -EIO;
+
+ if (ppd & SNB_PPD_DEV_TYPE)
+ ndev->dev_type = NTB_DEV_USD;
+ else
+ ndev->dev_type = NTB_DEV_DSD;
+
+ ndev->split_bar = (ppd & SNB_PPD_SPLIT_BAR) ? 1 : 0;
+
+ switch (ppd & SNB_PPD_CONN_TYPE) {
+ case NTB_CONN_B2B:
+ dev_info(&ndev->pdev->dev, "Conn Type = B2B\n");
+ ndev->conn_type = NTB_CONN_B2B;
+ break;
+ case NTB_CONN_RP:
+ dev_info(&ndev->pdev->dev, "Conn Type = RP\n");
+ ndev->conn_type = NTB_CONN_RP;
+ break;
+ case NTB_CONN_TRANSPARENT:
+ dev_info(&ndev->pdev->dev, "Conn Type = TRANSPARENT\n");
+ ndev->conn_type = NTB_CONN_TRANSPARENT;
+ /*
+ * This mode is default to USD/DSP. HW does not report
+ * properly in transparent mode as it has no knowledge of
+ * NTB. We will just force correct here.
+ */
+ ndev->dev_type = NTB_DEV_USD;
+
+ /*
+ * This is a way for transparent BAR to figure out if we
+ * are doing split BAR or not. There is no way for the hw
+ * on the transparent side to know and set the PPD.
+ */
+ bars_mask = pci_select_bars(ndev->pdev, IORESOURCE_MEM);
+ bars = hweight32(bars_mask);
+ if (bars == (HSX_SPLITBAR_MAX_MW + 1))
+ ndev->split_bar = 1;
+
+ break;
+ default:
+ dev_err(&ndev->pdev->dev, "Unknown PPD %x\n", ppd);
+ return -ENODEV;
+ }
+
+ ntb_max_mw_detect(ndev);
+
+ return 0;
+}
+
+static int ntb_atom_detect(struct ntb_device *ndev)
+{
+ int rc;
+ u32 ppd;
+
+ ndev->hw_type = BWD_HW;
+ ndev->limits.max_mw = BWD_MAX_MW;
+
+ rc = pci_read_config_dword(ndev->pdev, NTB_PPD_OFFSET, &ppd);
+ if (rc)
+ return rc;
+
+ switch ((ppd & BWD_PPD_CONN_TYPE) >> 8) {
+ case NTB_CONN_B2B:
+ dev_info(&ndev->pdev->dev, "Conn Type = B2B\n");
+ ndev->conn_type = NTB_CONN_B2B;
+ break;
+ case NTB_CONN_RP:
+ default:
+ dev_err(&ndev->pdev->dev, "Unsupported NTB configuration\n");
+ return -EINVAL;
+ }
+
+ if (ppd & BWD_PPD_DEV_TYPE)
+ ndev->dev_type = NTB_DEV_DSD;
+ else
+ ndev->dev_type = NTB_DEV_USD;
+
+ return 0;
+}
+
+static int ntb_device_detect(struct ntb_device *ndev)
+{
+ int rc;
+
+ if (is_ntb_xeon(ndev))
+ rc = ntb_xeon_detect(ndev);
+ else if (is_ntb_atom(ndev))
+ rc = ntb_atom_detect(ndev);
+ else
+ rc = -ENODEV;
+
+ dev_info(&ndev->pdev->dev, "Device Type = %s\n",
+ ndev->dev_type == NTB_DEV_USD ? "USD/DSP" : "DSD/USP");
+
+ return 0;
+}
+
+static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ struct ntb_device *ndev;
+ int rc, i;
+
+ ndev = kzalloc(sizeof(struct ntb_device), GFP_KERNEL);
+ if (!ndev)
+ return -ENOMEM;
+
+ ndev->pdev = pdev;
+
+ ntb_set_errata_flags(ndev);
+
+ ndev->link_status = NTB_LINK_DOWN;
+ pci_set_drvdata(pdev, ndev);
+ ntb_setup_debugfs(ndev);
+
+ rc = pci_enable_device(pdev);
+ if (rc)
+ goto err;
+
+ pci_set_master(ndev->pdev);
+
+ rc = ntb_device_detect(ndev);
+ if (rc)
+ goto err;
+
+ ndev->mw = kcalloc(ndev->limits.max_mw, sizeof(struct ntb_mw),
+ GFP_KERNEL);
+ if (!ndev->mw) {
+ rc = -ENOMEM;
+ goto err1;
+ }
+
+ if (ndev->split_bar)
+ rc = pci_request_selected_regions(pdev, NTB_SPLITBAR_MASK,
+ KBUILD_MODNAME);
+ else
+ rc = pci_request_selected_regions(pdev, NTB_BAR_MASK,
+ KBUILD_MODNAME);
+
+ if (rc)
+ goto err2;
+
+ ndev->reg_base = pci_ioremap_bar(pdev, NTB_BAR_MMIO);
+ if (!ndev->reg_base) {
+ dev_warn(&pdev->dev, "Cannot remap BAR 0\n");
+ rc = -EIO;
+ goto err3;
+ }
+
+ for (i = 0; i < ndev->limits.max_mw; i++) {
+ ndev->mw[i].bar_sz = pci_resource_len(pdev, MW_TO_BAR(i));
+
+ /*
+ * with the errata we need to steal last of the memory
+ * windows for workarounds and they point to MMIO registers.
+ */
+ if ((ndev->wa_flags & WA_SNB_ERR) &&
+ (i == (ndev->limits.max_mw - 1))) {
+ ndev->mw[i].vbase =
+ ioremap_nocache(pci_resource_start(pdev,
+ MW_TO_BAR(i)),
+ ndev->mw[i].bar_sz);
+ } else {
+ ndev->mw[i].vbase =
+ ioremap_wc(pci_resource_start(pdev,
+ MW_TO_BAR(i)),
+ ndev->mw[i].bar_sz);
+ }
+
+ dev_info(&pdev->dev, "MW %d size %llu\n", i,
+ (unsigned long long) ndev->mw[i].bar_sz);
+ if (!ndev->mw[i].vbase) {
+ dev_warn(&pdev->dev, "Cannot remap BAR %d\n",
+ MW_TO_BAR(i));
+ rc = -EIO;
+ goto err4;
+ }
+ }
+
+ rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
+ if (rc) {
+ rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (rc)
+ goto err4;
+
+ dev_warn(&pdev->dev, "Cannot DMA highmem\n");
+ }
+
+ rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
+ if (rc) {
+ rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (rc)
+ goto err4;
+
+ dev_warn(&pdev->dev, "Cannot DMA consistent highmem\n");
+ }
+
+ rc = ntb_device_setup(ndev);
+ if (rc)
+ goto err4;
+
+ rc = ntb_create_callbacks(ndev);
+ if (rc)
+ goto err5;
+
+ rc = ntb_setup_interrupts(ndev);
+ if (rc)
+ goto err6;
+
+ /* The scratchpad registers keep the values between rmmod/insmod,
+ * blast them now
+ */
+ for (i = 0; i < ndev->limits.max_spads; i++) {
+ ntb_write_local_spad(ndev, i, 0);
+ ntb_write_remote_spad(ndev, i, 0);
+ }
+
+ rc = ntb_transport_init(pdev);
+ if (rc)
+ goto err7;
+
+ ntb_hw_link_up(ndev);
+
+ return 0;
+
+err7:
+ ntb_free_interrupts(ndev);
+err6:
+ ntb_free_callbacks(ndev);
+err5:
+ ntb_device_free(ndev);
+err4:
+ for (i--; i >= 0; i--)
+ iounmap(ndev->mw[i].vbase);
+ iounmap(ndev->reg_base);
+err3:
+ if (ndev->split_bar)
+ pci_release_selected_regions(pdev, NTB_SPLITBAR_MASK);
+ else
+ pci_release_selected_regions(pdev, NTB_BAR_MASK);
+err2:
+ kfree(ndev->mw);
+err1:
+ pci_disable_device(pdev);
+err:
+ ntb_free_debugfs(ndev);
+ kfree(ndev);
+
+ dev_err(&pdev->dev, "Error loading %s module\n", KBUILD_MODNAME);
+ return rc;
+}
+
+static void ntb_pci_remove(struct pci_dev *pdev)
+{
+ struct ntb_device *ndev = pci_get_drvdata(pdev);
+ int i;
+
+ ntb_hw_link_down(ndev);
+
+ ntb_transport_free(ndev->ntb_transport);
+
+ ntb_free_interrupts(ndev);
+ ntb_free_callbacks(ndev);
+ ntb_device_free(ndev);
+
+ /* need to reset max_mw limits so we can unmap properly */
+ if (ndev->hw_type == SNB_HW)
+ ntb_max_mw_detect(ndev);
+
+ for (i = 0; i < ndev->limits.max_mw; i++)
+ iounmap(ndev->mw[i].vbase);
+
+ kfree(ndev->mw);
+ iounmap(ndev->reg_base);
+ if (ndev->split_bar)
+ pci_release_selected_regions(pdev, NTB_SPLITBAR_MASK);
+ else
+ pci_release_selected_regions(pdev, NTB_BAR_MASK);
+ pci_disable_device(pdev);
+ ntb_free_debugfs(ndev);
+ kfree(ndev);
+}
+
+static struct pci_driver ntb_pci_driver = {
+ .name = KBUILD_MODNAME,
+ .id_table = ntb_pci_tbl,
+ .probe = ntb_pci_probe,
+ .remove = ntb_pci_remove,
+};
+
+module_pci_driver(ntb_pci_driver);
diff --git a/kernel/drivers/ntb/ntb_hw.h b/kernel/drivers/ntb/ntb_hw.h
new file mode 100644
index 000000000..96de5fc95
--- /dev/null
+++ b/kernel/drivers/ntb/ntb_hw.h
@@ -0,0 +1,256 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copy
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Intel PCIe NTB Linux driver
+ *
+ * Contact Information:
+ * Jon Mason <jon.mason@intel.com>
+ */
+#include <linux/ntb.h>
+
+#define PCI_DEVICE_ID_INTEL_NTB_B2B_JSF 0x3725
+#define PCI_DEVICE_ID_INTEL_NTB_PS_JSF 0x3726
+#define PCI_DEVICE_ID_INTEL_NTB_SS_JSF 0x3727
+#define PCI_DEVICE_ID_INTEL_NTB_B2B_SNB 0x3C0D
+#define PCI_DEVICE_ID_INTEL_NTB_PS_SNB 0x3C0E
+#define PCI_DEVICE_ID_INTEL_NTB_SS_SNB 0x3C0F
+#define PCI_DEVICE_ID_INTEL_NTB_B2B_IVT 0x0E0D
+#define PCI_DEVICE_ID_INTEL_NTB_PS_IVT 0x0E0E
+#define PCI_DEVICE_ID_INTEL_NTB_SS_IVT 0x0E0F
+#define PCI_DEVICE_ID_INTEL_NTB_B2B_HSX 0x2F0D
+#define PCI_DEVICE_ID_INTEL_NTB_PS_HSX 0x2F0E
+#define PCI_DEVICE_ID_INTEL_NTB_SS_HSX 0x2F0F
+#define PCI_DEVICE_ID_INTEL_NTB_B2B_BWD 0x0C4E
+
+#ifndef readq
+static inline u64 readq(void __iomem *addr)
+{
+ return readl(addr) | (((u64) readl(addr + 4)) << 32LL);
+}
+#endif
+
+#ifndef writeq
+static inline void writeq(u64 val, void __iomem *addr)
+{
+ writel(val & 0xffffffff, addr);
+ writel(val >> 32, addr + 4);
+}
+#endif
+
+#define NTB_BAR_MMIO 0
+#define NTB_BAR_23 2
+#define NTB_BAR_4 4
+#define NTB_BAR_5 5
+
+#define NTB_BAR_MASK ((1 << NTB_BAR_MMIO) | (1 << NTB_BAR_23) |\
+ (1 << NTB_BAR_4))
+#define NTB_SPLITBAR_MASK ((1 << NTB_BAR_MMIO) | (1 << NTB_BAR_23) |\
+ (1 << NTB_BAR_4) | (1 << NTB_BAR_5))
+
+#define NTB_HB_TIMEOUT msecs_to_jiffies(1000)
+
+enum ntb_hw_event {
+ NTB_EVENT_SW_EVENT0 = 0,
+ NTB_EVENT_SW_EVENT1,
+ NTB_EVENT_SW_EVENT2,
+ NTB_EVENT_HW_ERROR,
+ NTB_EVENT_HW_LINK_UP,
+ NTB_EVENT_HW_LINK_DOWN,
+};
+
+struct ntb_mw {
+ dma_addr_t phys_addr;
+ void __iomem *vbase;
+ resource_size_t bar_sz;
+};
+
+struct ntb_db_cb {
+ int (*callback)(void *data, int db_num);
+ unsigned int db_num;
+ void *data;
+ struct ntb_device *ndev;
+ struct tasklet_struct irq_work;
+};
+
+#define WA_SNB_ERR 0x00000001
+
+struct ntb_device {
+ struct pci_dev *pdev;
+ struct msix_entry *msix_entries;
+ void __iomem *reg_base;
+ struct ntb_mw *mw;
+ struct {
+ unsigned char max_mw;
+ unsigned char max_spads;
+ unsigned char max_db_bits;
+ unsigned char msix_cnt;
+ } limits;
+ struct {
+ void __iomem *ldb;
+ void __iomem *ldb_mask;
+ void __iomem *rdb;
+ void __iomem *bar2_xlat;
+ void __iomem *bar4_xlat;
+ void __iomem *bar5_xlat;
+ void __iomem *spad_write;
+ void __iomem *spad_read;
+ void __iomem *lnk_cntl;
+ void __iomem *lnk_stat;
+ void __iomem *spci_cmd;
+ } reg_ofs;
+ struct ntb_transport *ntb_transport;
+ void (*event_cb)(void *handle, enum ntb_hw_event event);
+
+ struct ntb_db_cb *db_cb;
+ unsigned char hw_type;
+ unsigned char conn_type;
+ unsigned char dev_type;
+ unsigned char num_msix;
+ unsigned char bits_per_vector;
+ unsigned char max_cbs;
+ unsigned char link_width;
+ unsigned char link_speed;
+ unsigned char link_status;
+ unsigned char split_bar;
+
+ struct delayed_work hb_timer;
+ unsigned long last_ts;
+
+ struct delayed_work lr_timer;
+
+ struct dentry *debugfs_dir;
+ struct dentry *debugfs_info;
+
+ unsigned int wa_flags;
+};
+
+/**
+ * ntb_max_cbs() - return the max callbacks
+ * @ndev: pointer to ntb_device instance
+ *
+ * Given the ntb pointer, return the maximum number of callbacks
+ *
+ * RETURNS: the maximum number of callbacks
+ */
+static inline unsigned char ntb_max_cbs(struct ntb_device *ndev)
+{
+ return ndev->max_cbs;
+}
+
+/**
+ * ntb_max_mw() - return the max number of memory windows
+ * @ndev: pointer to ntb_device instance
+ *
+ * Given the ntb pointer, return the maximum number of memory windows
+ *
+ * RETURNS: the maximum number of memory windows
+ */
+static inline unsigned char ntb_max_mw(struct ntb_device *ndev)
+{
+ return ndev->limits.max_mw;
+}
+
+/**
+ * ntb_hw_link_status() - return the hardware link status
+ * @ndev: pointer to ntb_device instance
+ *
+ * Returns true if the hardware is connected to the remote system
+ *
+ * RETURNS: true or false based on the hardware link state
+ */
+static inline bool ntb_hw_link_status(struct ntb_device *ndev)
+{
+ return ndev->link_status == NTB_LINK_UP;
+}
+
+/**
+ * ntb_query_pdev() - return the pci_dev pointer
+ * @ndev: pointer to ntb_device instance
+ *
+ * Given the ntb pointer, return the pci_dev pointer for the NTB hardware device
+ *
+ * RETURNS: a pointer to the ntb pci_dev
+ */
+static inline struct pci_dev *ntb_query_pdev(struct ntb_device *ndev)
+{
+ return ndev->pdev;
+}
+
+/**
+ * ntb_query_debugfs() - return the debugfs pointer
+ * @ndev: pointer to ntb_device instance
+ *
+ * Given the ntb pointer, return the debugfs directory pointer for the NTB
+ * hardware device
+ *
+ * RETURNS: a pointer to the debugfs directory
+ */
+static inline struct dentry *ntb_query_debugfs(struct ntb_device *ndev)
+{
+ return ndev->debugfs_dir;
+}
+
+struct ntb_device *ntb_register_transport(struct pci_dev *pdev,
+ void *transport);
+void ntb_unregister_transport(struct ntb_device *ndev);
+void ntb_set_mw_addr(struct ntb_device *ndev, unsigned int mw, u64 addr);
+int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx,
+ void *data, int (*db_cb_func)(void *data,
+ int db_num));
+void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx);
+int ntb_register_event_callback(struct ntb_device *ndev,
+ void (*event_cb_func)(void *handle,
+ enum ntb_hw_event event));
+void ntb_unregister_event_callback(struct ntb_device *ndev);
+int ntb_get_max_spads(struct ntb_device *ndev);
+int ntb_write_local_spad(struct ntb_device *ndev, unsigned int idx, u32 val);
+int ntb_read_local_spad(struct ntb_device *ndev, unsigned int idx, u32 *val);
+int ntb_write_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 val);
+int ntb_read_remote_spad(struct ntb_device *ndev, unsigned int idx, u32 *val);
+resource_size_t ntb_get_mw_base(struct ntb_device *ndev, unsigned int mw);
+void __iomem *ntb_get_mw_vbase(struct ntb_device *ndev, unsigned int mw);
+u64 ntb_get_mw_size(struct ntb_device *ndev, unsigned int mw);
+void ntb_ring_doorbell(struct ntb_device *ndev, unsigned int idx);
+void *ntb_find_transport(struct pci_dev *pdev);
+
+int ntb_transport_init(struct pci_dev *pdev);
+void ntb_transport_free(void *transport);
diff --git a/kernel/drivers/ntb/ntb_regs.h b/kernel/drivers/ntb/ntb_regs.h
new file mode 100644
index 000000000..f028ff81f
--- /dev/null
+++ b/kernel/drivers/ntb/ntb_regs.h
@@ -0,0 +1,177 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copy
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Intel PCIe NTB Linux driver
+ *
+ * Contact Information:
+ * Jon Mason <jon.mason@intel.com>
+ */
+
+#define NTB_LINK_STATUS_ACTIVE 0x2000
+#define NTB_LINK_SPEED_MASK 0x000f
+#define NTB_LINK_WIDTH_MASK 0x03f0
+
+#define SNB_MSIX_CNT 4
+#define SNB_MAX_B2B_SPADS 16
+#define SNB_MAX_COMPAT_SPADS 16
+/* Reserve the uppermost bit for link interrupt */
+#define SNB_MAX_DB_BITS 15
+#define SNB_LINK_DB 15
+#define SNB_DB_BITS_PER_VEC 5
+#define HSX_SPLITBAR_MAX_MW 3
+#define SNB_MAX_MW 2
+#define SNB_ERRATA_MAX_MW 1
+
+#define SNB_DB_HW_LINK 0x8000
+
+#define SNB_UNCERRSTS_OFFSET 0x014C
+#define SNB_CORERRSTS_OFFSET 0x0158
+#define SNB_LINK_STATUS_OFFSET 0x01A2
+#define SNB_PCICMD_OFFSET 0x0504
+#define SNB_DEVCTRL_OFFSET 0x0598
+#define SNB_DEVSTS_OFFSET 0x059A
+#define SNB_SLINK_STATUS_OFFSET 0x05A2
+
+#define SNB_PBAR2LMT_OFFSET 0x0000
+#define SNB_PBAR4LMT_OFFSET 0x0008
+#define SNB_PBAR5LMT_OFFSET 0x000C
+#define SNB_PBAR2XLAT_OFFSET 0x0010
+#define SNB_PBAR4XLAT_OFFSET 0x0018
+#define SNB_PBAR5XLAT_OFFSET 0x001C
+#define SNB_SBAR2LMT_OFFSET 0x0020
+#define SNB_SBAR4LMT_OFFSET 0x0028
+#define SNB_SBAR5LMT_OFFSET 0x002C
+#define SNB_SBAR2XLAT_OFFSET 0x0030
+#define SNB_SBAR4XLAT_OFFSET 0x0038
+#define SNB_SBAR5XLAT_OFFSET 0x003C
+#define SNB_SBAR0BASE_OFFSET 0x0040
+#define SNB_SBAR2BASE_OFFSET 0x0048
+#define SNB_SBAR4BASE_OFFSET 0x0050
+#define SNB_SBAR5BASE_OFFSET 0x0054
+#define SNB_NTBCNTL_OFFSET 0x0058
+#define SNB_SBDF_OFFSET 0x005C
+#define SNB_PDOORBELL_OFFSET 0x0060
+#define SNB_PDBMSK_OFFSET 0x0062
+#define SNB_SDOORBELL_OFFSET 0x0064
+#define SNB_SDBMSK_OFFSET 0x0066
+#define SNB_USMEMMISS_OFFSET 0x0070
+#define SNB_SPAD_OFFSET 0x0080
+#define SNB_SPADSEMA4_OFFSET 0x00c0
+#define SNB_WCCNTRL_OFFSET 0x00e0
+#define SNB_B2B_SPAD_OFFSET 0x0100
+#define SNB_B2B_DOORBELL_OFFSET 0x0140
+#define SNB_B2B_XLAT_OFFSETL 0x0144
+#define SNB_B2B_XLAT_OFFSETU 0x0148
+
+/*
+ * The addresses are setup so the 32bit BARs can function. Thus
+ * the addresses are all in 32bit space
+ */
+#define SNB_MBAR01_USD_ADDR 0x000000002100000CULL
+#define SNB_MBAR23_USD_ADDR 0x000000004100000CULL
+#define SNB_MBAR4_USD_ADDR 0x000000008100000CULL
+#define SNB_MBAR5_USD_ADDR 0x00000000A100000CULL
+#define SNB_MBAR01_DSD_ADDR 0x000000002000000CULL
+#define SNB_MBAR23_DSD_ADDR 0x000000004000000CULL
+#define SNB_MBAR4_DSD_ADDR 0x000000008000000CULL
+#define SNB_MBAR5_DSD_ADDR 0x00000000A000000CULL
+
+#define BWD_MSIX_CNT 34
+#define BWD_MAX_SPADS 16
+#define BWD_MAX_DB_BITS 34
+#define BWD_DB_BITS_PER_VEC 1
+#define BWD_MAX_MW 2
+
+#define BWD_PCICMD_OFFSET 0xb004
+#define BWD_MBAR23_OFFSET 0xb018
+#define BWD_MBAR45_OFFSET 0xb020
+#define BWD_DEVCTRL_OFFSET 0xb048
+#define BWD_LINK_STATUS_OFFSET 0xb052
+#define BWD_ERRCORSTS_OFFSET 0xb110
+
+#define BWD_SBAR2XLAT_OFFSET 0x0008
+#define BWD_SBAR4XLAT_OFFSET 0x0010
+#define BWD_PDOORBELL_OFFSET 0x0020
+#define BWD_PDBMSK_OFFSET 0x0028
+#define BWD_NTBCNTL_OFFSET 0x0060
+#define BWD_EBDF_OFFSET 0x0064
+#define BWD_SPAD_OFFSET 0x0080
+#define BWD_SPADSEMA_OFFSET 0x00c0
+#define BWD_STKYSPAD_OFFSET 0x00c4
+#define BWD_PBAR2XLAT_OFFSET 0x8008
+#define BWD_PBAR4XLAT_OFFSET 0x8010
+#define BWD_B2B_DOORBELL_OFFSET 0x8020
+#define BWD_B2B_SPAD_OFFSET 0x8080
+#define BWD_B2B_SPADSEMA_OFFSET 0x80c0
+#define BWD_B2B_STKYSPAD_OFFSET 0x80c4
+
+#define BWD_MODPHY_PCSREG4 0x1c004
+#define BWD_MODPHY_PCSREG6 0x1c006
+
+#define BWD_IP_BASE 0xC000
+#define BWD_DESKEWSTS_OFFSET (BWD_IP_BASE + 0x3024)
+#define BWD_LTSSMERRSTS0_OFFSET (BWD_IP_BASE + 0x3180)
+#define BWD_LTSSMSTATEJMP_OFFSET (BWD_IP_BASE + 0x3040)
+#define BWD_IBSTERRRCRVSTS0_OFFSET (BWD_IP_BASE + 0x3324)
+
+#define BWD_DESKEWSTS_DBERR (1 << 15)
+#define BWD_LTSSMERRSTS0_UNEXPECTEDEI (1 << 20)
+#define BWD_LTSSMSTATEJMP_FORCEDETECT (1 << 2)
+#define BWD_IBIST_ERR_OFLOW 0x7FFF7FFF
+
+#define NTB_CNTL_CFG_LOCK (1 << 0)
+#define NTB_CNTL_LINK_DISABLE (1 << 1)
+#define NTB_CNTL_S2P_BAR23_SNOOP (1 << 2)
+#define NTB_CNTL_P2S_BAR23_SNOOP (1 << 4)
+#define NTB_CNTL_S2P_BAR4_SNOOP (1 << 6)
+#define NTB_CNTL_P2S_BAR4_SNOOP (1 << 8)
+#define NTB_CNTL_S2P_BAR5_SNOOP (1 << 12)
+#define NTB_CNTL_P2S_BAR5_SNOOP (1 << 14)
+#define BWD_CNTL_LINK_DOWN (1 << 16)
+
+#define NTB_PPD_OFFSET 0x00D4
+#define SNB_PPD_CONN_TYPE 0x0003
+#define SNB_PPD_DEV_TYPE 0x0010
+#define SNB_PPD_SPLIT_BAR (1 << 6)
+#define BWD_PPD_INIT_LINK 0x0008
+#define BWD_PPD_CONN_TYPE 0x0300
+#define BWD_PPD_DEV_TYPE 0x1000
diff --git a/kernel/drivers/ntb/ntb_transport.c b/kernel/drivers/ntb/ntb_transport.c
new file mode 100644
index 000000000..e9bf2f47b
--- /dev/null
+++ b/kernel/drivers/ntb/ntb_transport.c
@@ -0,0 +1,1776 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copy
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Intel PCIe NTB Linux driver
+ *
+ * Contact Information:
+ * Jon Mason <jon.mason@intel.com>
+ */
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include "ntb_hw.h"
+
+#define NTB_TRANSPORT_VERSION 3
+
+static unsigned int transport_mtu = 0x401E;
+module_param(transport_mtu, uint, 0644);
+MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets");
+
+static unsigned char max_num_clients;
+module_param(max_num_clients, byte, 0644);
+MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients");
+
+static unsigned int copy_bytes = 1024;
+module_param(copy_bytes, uint, 0644);
+MODULE_PARM_DESC(copy_bytes, "Threshold under which NTB will use the CPU to copy instead of DMA");
+
+struct ntb_queue_entry {
+ /* ntb_queue list reference */
+ struct list_head entry;
+ /* pointers to data to be transfered */
+ void *cb_data;
+ void *buf;
+ unsigned int len;
+ unsigned int flags;
+
+ struct ntb_transport_qp *qp;
+ union {
+ struct ntb_payload_header __iomem *tx_hdr;
+ struct ntb_payload_header *rx_hdr;
+ };
+ unsigned int index;
+};
+
+struct ntb_rx_info {
+ unsigned int entry;
+};
+
+struct ntb_transport_qp {
+ struct ntb_transport *transport;
+ struct ntb_device *ndev;
+ void *cb_data;
+ struct dma_chan *dma_chan;
+
+ bool client_ready;
+ bool qp_link;
+ u8 qp_num; /* Only 64 QP's are allowed. 0-63 */
+
+ struct ntb_rx_info __iomem *rx_info;
+ struct ntb_rx_info *remote_rx_info;
+
+ void (*tx_handler)(struct ntb_transport_qp *qp, void *qp_data,
+ void *data, int len);
+ struct list_head tx_free_q;
+ spinlock_t ntb_tx_free_q_lock;
+ void __iomem *tx_mw;
+ dma_addr_t tx_mw_phys;
+ unsigned int tx_index;
+ unsigned int tx_max_entry;
+ unsigned int tx_max_frame;
+
+ void (*rx_handler)(struct ntb_transport_qp *qp, void *qp_data,
+ void *data, int len);
+ struct list_head rx_pend_q;
+ struct list_head rx_free_q;
+ spinlock_t ntb_rx_pend_q_lock;
+ spinlock_t ntb_rx_free_q_lock;
+ void *rx_buff;
+ unsigned int rx_index;
+ unsigned int rx_max_entry;
+ unsigned int rx_max_frame;
+ dma_cookie_t last_cookie;
+
+ void (*event_handler)(void *data, int status);
+ struct delayed_work link_work;
+ struct work_struct link_cleanup;
+
+ struct dentry *debugfs_dir;
+ struct dentry *debugfs_stats;
+
+ /* Stats */
+ u64 rx_bytes;
+ u64 rx_pkts;
+ u64 rx_ring_empty;
+ u64 rx_err_no_buf;
+ u64 rx_err_oflow;
+ u64 rx_err_ver;
+ u64 rx_memcpy;
+ u64 rx_async;
+ u64 tx_bytes;
+ u64 tx_pkts;
+ u64 tx_ring_full;
+ u64 tx_err_no_buf;
+ u64 tx_memcpy;
+ u64 tx_async;
+};
+
+struct ntb_transport_mw {
+ size_t size;
+ void *virt_addr;
+ dma_addr_t dma_addr;
+};
+
+struct ntb_transport_client_dev {
+ struct list_head entry;
+ struct device dev;
+};
+
+struct ntb_transport {
+ struct list_head entry;
+ struct list_head client_devs;
+
+ struct ntb_device *ndev;
+ struct ntb_transport_mw *mw;
+ struct ntb_transport_qp *qps;
+ unsigned int max_qps;
+ unsigned long qp_bitmap;
+ bool transport_link;
+ struct delayed_work link_work;
+ struct work_struct link_cleanup;
+};
+
+enum {
+ DESC_DONE_FLAG = 1 << 0,
+ LINK_DOWN_FLAG = 1 << 1,
+};
+
+struct ntb_payload_header {
+ unsigned int ver;
+ unsigned int len;
+ unsigned int flags;
+};
+
+enum {
+ VERSION = 0,
+ QP_LINKS,
+ NUM_QPS,
+ NUM_MWS,
+ MW0_SZ_HIGH,
+ MW0_SZ_LOW,
+ MW1_SZ_HIGH,
+ MW1_SZ_LOW,
+ MAX_SPAD,
+};
+
+#define QP_TO_MW(ndev, qp) ((qp) % ntb_max_mw(ndev))
+#define NTB_QP_DEF_NUM_ENTRIES 100
+#define NTB_LINK_DOWN_TIMEOUT 10
+
+static int ntb_match_bus(struct device *dev, struct device_driver *drv)
+{
+ return !strncmp(dev_name(dev), drv->name, strlen(drv->name));
+}
+
+static int ntb_client_probe(struct device *dev)
+{
+ const struct ntb_client *drv = container_of(dev->driver,
+ struct ntb_client, driver);
+ struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev);
+ int rc = -EINVAL;
+
+ get_device(dev);
+ if (drv && drv->probe)
+ rc = drv->probe(pdev);
+ if (rc)
+ put_device(dev);
+
+ return rc;
+}
+
+static int ntb_client_remove(struct device *dev)
+{
+ const struct ntb_client *drv = container_of(dev->driver,
+ struct ntb_client, driver);
+ struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev);
+
+ if (drv && drv->remove)
+ drv->remove(pdev);
+
+ put_device(dev);
+
+ return 0;
+}
+
+static struct bus_type ntb_bus_type = {
+ .name = "ntb_bus",
+ .match = ntb_match_bus,
+ .probe = ntb_client_probe,
+ .remove = ntb_client_remove,
+};
+
+static LIST_HEAD(ntb_transport_list);
+
+static int ntb_bus_init(struct ntb_transport *nt)
+{
+ if (list_empty(&ntb_transport_list)) {
+ int rc = bus_register(&ntb_bus_type);
+ if (rc)
+ return rc;
+ }
+
+ list_add(&nt->entry, &ntb_transport_list);
+
+ return 0;
+}
+
+static void ntb_bus_remove(struct ntb_transport *nt)
+{
+ struct ntb_transport_client_dev *client_dev, *cd;
+
+ list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) {
+ dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n",
+ dev_name(&client_dev->dev));
+ list_del(&client_dev->entry);
+ device_unregister(&client_dev->dev);
+ }
+
+ list_del(&nt->entry);
+
+ if (list_empty(&ntb_transport_list))
+ bus_unregister(&ntb_bus_type);
+}
+
+static void ntb_client_release(struct device *dev)
+{
+ struct ntb_transport_client_dev *client_dev;
+ client_dev = container_of(dev, struct ntb_transport_client_dev, dev);
+
+ kfree(client_dev);
+}
+
+/**
+ * ntb_unregister_client_dev - Unregister NTB client device
+ * @device_name: Name of NTB client device
+ *
+ * Unregister an NTB client device with the NTB transport layer
+ */
+void ntb_unregister_client_dev(char *device_name)
+{
+ struct ntb_transport_client_dev *client, *cd;
+ struct ntb_transport *nt;
+
+ list_for_each_entry(nt, &ntb_transport_list, entry)
+ list_for_each_entry_safe(client, cd, &nt->client_devs, entry)
+ if (!strncmp(dev_name(&client->dev), device_name,
+ strlen(device_name))) {
+ list_del(&client->entry);
+ device_unregister(&client->dev);
+ }
+}
+EXPORT_SYMBOL_GPL(ntb_unregister_client_dev);
+
+/**
+ * ntb_register_client_dev - Register NTB client device
+ * @device_name: Name of NTB client device
+ *
+ * Register an NTB client device with the NTB transport layer
+ */
+int ntb_register_client_dev(char *device_name)
+{
+ struct ntb_transport_client_dev *client_dev;
+ struct ntb_transport *nt;
+ int rc, i = 0;
+
+ if (list_empty(&ntb_transport_list))
+ return -ENODEV;
+
+ list_for_each_entry(nt, &ntb_transport_list, entry) {
+ struct device *dev;
+
+ client_dev = kzalloc(sizeof(struct ntb_transport_client_dev),
+ GFP_KERNEL);
+ if (!client_dev) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ dev = &client_dev->dev;
+
+ /* setup and register client devices */
+ dev_set_name(dev, "%s%d", device_name, i);
+ dev->bus = &ntb_bus_type;
+ dev->release = ntb_client_release;
+ dev->parent = &ntb_query_pdev(nt->ndev)->dev;
+
+ rc = device_register(dev);
+ if (rc) {
+ kfree(client_dev);
+ goto err;
+ }
+
+ list_add_tail(&client_dev->entry, &nt->client_devs);
+ i++;
+ }
+
+ return 0;
+
+err:
+ ntb_unregister_client_dev(device_name);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(ntb_register_client_dev);
+
+/**
+ * ntb_register_client - Register NTB client driver
+ * @drv: NTB client driver to be registered
+ *
+ * Register an NTB client driver with the NTB transport layer
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_register_client(struct ntb_client *drv)
+{
+ drv->driver.bus = &ntb_bus_type;
+
+ if (list_empty(&ntb_transport_list))
+ return -ENODEV;
+
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(ntb_register_client);
+
+/**
+ * ntb_unregister_client - Unregister NTB client driver
+ * @drv: NTB client driver to be unregistered
+ *
+ * Unregister an NTB client driver with the NTB transport layer
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+void ntb_unregister_client(struct ntb_client *drv)
+{
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(ntb_unregister_client);
+
+static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count,
+ loff_t *offp)
+{
+ struct ntb_transport_qp *qp;
+ char *buf;
+ ssize_t ret, out_offset, out_count;
+
+ out_count = 1000;
+
+ buf = kmalloc(out_count, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ qp = filp->private_data;
+ out_offset = 0;
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "NTB QP stats\n");
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_bytes - \t%llu\n", qp->rx_bytes);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_pkts - \t%llu\n", qp->rx_pkts);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_memcpy - \t%llu\n", qp->rx_memcpy);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_async - \t%llu\n", qp->rx_async);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_ring_empty - %llu\n", qp->rx_ring_empty);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_err_no_buf - %llu\n", qp->rx_err_no_buf);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_err_oflow - \t%llu\n", qp->rx_err_oflow);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_err_ver - \t%llu\n", qp->rx_err_ver);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_buff - \t%p\n", qp->rx_buff);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_index - \t%u\n", qp->rx_index);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "rx_max_entry - \t%u\n", qp->rx_max_entry);
+
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_bytes - \t%llu\n", qp->tx_bytes);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_pkts - \t%llu\n", qp->tx_pkts);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_memcpy - \t%llu\n", qp->tx_memcpy);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_async - \t%llu\n", qp->tx_async);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_ring_full - \t%llu\n", qp->tx_ring_full);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_err_no_buf - %llu\n", qp->tx_err_no_buf);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_mw - \t%p\n", qp->tx_mw);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_index - \t%u\n", qp->tx_index);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "tx_max_entry - \t%u\n", qp->tx_max_entry);
+
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "\nQP Link %s\n", (qp->qp_link == NTB_LINK_UP) ?
+ "Up" : "Down");
+ if (out_offset > out_count)
+ out_offset = out_count;
+
+ ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
+ kfree(buf);
+ return ret;
+}
+
+static const struct file_operations ntb_qp_debugfs_stats = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = debugfs_read,
+};
+
+static void ntb_list_add(spinlock_t *lock, struct list_head *entry,
+ struct list_head *list)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(lock, flags);
+ list_add_tail(entry, list);
+ spin_unlock_irqrestore(lock, flags);
+}
+
+static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock,
+ struct list_head *list)
+{
+ struct ntb_queue_entry *entry;
+ unsigned long flags;
+
+ spin_lock_irqsave(lock, flags);
+ if (list_empty(list)) {
+ entry = NULL;
+ goto out;
+ }
+ entry = list_first_entry(list, struct ntb_queue_entry, entry);
+ list_del(&entry->entry);
+out:
+ spin_unlock_irqrestore(lock, flags);
+
+ return entry;
+}
+
+static void ntb_transport_setup_qp_mw(struct ntb_transport *nt,
+ unsigned int qp_num)
+{
+ struct ntb_transport_qp *qp = &nt->qps[qp_num];
+ unsigned int rx_size, num_qps_mw;
+ u8 mw_num, mw_max;
+ unsigned int i;
+
+ mw_max = ntb_max_mw(nt->ndev);
+ mw_num = QP_TO_MW(nt->ndev, qp_num);
+
+ WARN_ON(nt->mw[mw_num].virt_addr == NULL);
+
+ if (nt->max_qps % mw_max && mw_num + 1 < nt->max_qps / mw_max)
+ num_qps_mw = nt->max_qps / mw_max + 1;
+ else
+ num_qps_mw = nt->max_qps / mw_max;
+
+ rx_size = (unsigned int) nt->mw[mw_num].size / num_qps_mw;
+ qp->rx_buff = nt->mw[mw_num].virt_addr + qp_num / mw_max * rx_size;
+ rx_size -= sizeof(struct ntb_rx_info);
+
+ qp->remote_rx_info = qp->rx_buff + rx_size;
+
+ /* Due to housekeeping, there must be atleast 2 buffs */
+ qp->rx_max_frame = min(transport_mtu, rx_size / 2);
+ qp->rx_max_entry = rx_size / qp->rx_max_frame;
+ qp->rx_index = 0;
+
+ qp->remote_rx_info->entry = qp->rx_max_entry - 1;
+
+ /* setup the hdr offsets with 0's */
+ for (i = 0; i < qp->rx_max_entry; i++) {
+ void *offset = qp->rx_buff + qp->rx_max_frame * (i + 1) -
+ sizeof(struct ntb_payload_header);
+ memset(offset, 0, sizeof(struct ntb_payload_header));
+ }
+
+ qp->rx_pkts = 0;
+ qp->tx_pkts = 0;
+ qp->tx_index = 0;
+}
+
+static void ntb_free_mw(struct ntb_transport *nt, int num_mw)
+{
+ struct ntb_transport_mw *mw = &nt->mw[num_mw];
+ struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
+
+ if (!mw->virt_addr)
+ return;
+
+ dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr);
+ mw->virt_addr = NULL;
+}
+
+static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
+{
+ struct ntb_transport_mw *mw = &nt->mw[num_mw];
+ struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
+
+ /* No need to re-setup */
+ if (mw->size == ALIGN(size, 4096))
+ return 0;
+
+ if (mw->size != 0)
+ ntb_free_mw(nt, num_mw);
+
+ /* Alloc memory for receiving data. Must be 4k aligned */
+ mw->size = ALIGN(size, 4096);
+
+ mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr,
+ GFP_KERNEL);
+ if (!mw->virt_addr) {
+ mw->size = 0;
+ dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n",
+ (int) mw->size);
+ return -ENOMEM;
+ }
+
+ /*
+ * we must ensure that the memory address allocated is BAR size
+ * aligned in order for the XLAT register to take the value. This
+ * is a requirement of the hardware. It is recommended to setup CMA
+ * for BAR sizes equal or greater than 4MB.
+ */
+ if (!IS_ALIGNED(mw->dma_addr, mw->size)) {
+ dev_err(&pdev->dev, "DMA memory %pad not aligned to BAR size\n",
+ &mw->dma_addr);
+ ntb_free_mw(nt, num_mw);
+ return -ENOMEM;
+ }
+
+ /* Notify HW the memory location of the receive buffer */
+ ntb_set_mw_addr(nt->ndev, num_mw, mw->dma_addr);
+
+ return 0;
+}
+
+static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp)
+{
+ struct ntb_transport *nt = qp->transport;
+ struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
+
+ if (qp->qp_link == NTB_LINK_DOWN) {
+ cancel_delayed_work_sync(&qp->link_work);
+ return;
+ }
+
+ if (qp->event_handler)
+ qp->event_handler(qp->cb_data, NTB_LINK_DOWN);
+
+ dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num);
+ qp->qp_link = NTB_LINK_DOWN;
+}
+
+static void ntb_qp_link_cleanup_work(struct work_struct *work)
+{
+ struct ntb_transport_qp *qp = container_of(work,
+ struct ntb_transport_qp,
+ link_cleanup);
+ struct ntb_transport *nt = qp->transport;
+
+ ntb_qp_link_cleanup(qp);
+
+ if (nt->transport_link == NTB_LINK_UP)
+ schedule_delayed_work(&qp->link_work,
+ msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
+}
+
+static void ntb_qp_link_down(struct ntb_transport_qp *qp)
+{
+ schedule_work(&qp->link_cleanup);
+}
+
+static void ntb_transport_link_cleanup(struct ntb_transport *nt)
+{
+ int i;
+
+ /* Pass along the info to any clients */
+ for (i = 0; i < nt->max_qps; i++)
+ if (!test_bit(i, &nt->qp_bitmap))
+ ntb_qp_link_cleanup(&nt->qps[i]);
+
+ if (nt->transport_link == NTB_LINK_DOWN)
+ cancel_delayed_work_sync(&nt->link_work);
+ else
+ nt->transport_link = NTB_LINK_DOWN;
+
+ /* The scratchpad registers keep the values if the remote side
+ * goes down, blast them now to give them a sane value the next
+ * time they are accessed
+ */
+ for (i = 0; i < MAX_SPAD; i++)
+ ntb_write_local_spad(nt->ndev, i, 0);
+}
+
+static void ntb_transport_link_cleanup_work(struct work_struct *work)
+{
+ struct ntb_transport *nt = container_of(work, struct ntb_transport,
+ link_cleanup);
+
+ ntb_transport_link_cleanup(nt);
+}
+
+static void ntb_transport_event_callback(void *data, enum ntb_hw_event event)
+{
+ struct ntb_transport *nt = data;
+
+ switch (event) {
+ case NTB_EVENT_HW_LINK_UP:
+ schedule_delayed_work(&nt->link_work, 0);
+ break;
+ case NTB_EVENT_HW_LINK_DOWN:
+ schedule_work(&nt->link_cleanup);
+ break;
+ default:
+ BUG();
+ }
+}
+
+static void ntb_transport_link_work(struct work_struct *work)
+{
+ struct ntb_transport *nt = container_of(work, struct ntb_transport,
+ link_work.work);
+ struct ntb_device *ndev = nt->ndev;
+ struct pci_dev *pdev = ntb_query_pdev(ndev);
+ u32 val;
+ int rc, i;
+
+ /* send the local info, in the opposite order of the way we read it */
+ for (i = 0; i < ntb_max_mw(ndev); i++) {
+ rc = ntb_write_remote_spad(ndev, MW0_SZ_HIGH + (i * 2),
+ ntb_get_mw_size(ndev, i) >> 32);
+ if (rc) {
+ dev_err(&pdev->dev, "Error writing %u to remote spad %d\n",
+ (u32)(ntb_get_mw_size(ndev, i) >> 32),
+ MW0_SZ_HIGH + (i * 2));
+ goto out;
+ }
+
+ rc = ntb_write_remote_spad(ndev, MW0_SZ_LOW + (i * 2),
+ (u32) ntb_get_mw_size(ndev, i));
+ if (rc) {
+ dev_err(&pdev->dev, "Error writing %u to remote spad %d\n",
+ (u32) ntb_get_mw_size(ndev, i),
+ MW0_SZ_LOW + (i * 2));
+ goto out;
+ }
+ }
+
+ rc = ntb_write_remote_spad(ndev, NUM_MWS, ntb_max_mw(ndev));
+ if (rc) {
+ dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
+ ntb_max_mw(ndev), NUM_MWS);
+ goto out;
+ }
+
+ rc = ntb_write_remote_spad(ndev, NUM_QPS, nt->max_qps);
+ if (rc) {
+ dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
+ nt->max_qps, NUM_QPS);
+ goto out;
+ }
+
+ rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION);
+ if (rc) {
+ dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
+ NTB_TRANSPORT_VERSION, VERSION);
+ goto out;
+ }
+
+ /* Query the remote side for its info */
+ rc = ntb_read_remote_spad(ndev, VERSION, &val);
+ if (rc) {
+ dev_err(&pdev->dev, "Error reading remote spad %d\n", VERSION);
+ goto out;
+ }
+
+ if (val != NTB_TRANSPORT_VERSION)
+ goto out;
+ dev_dbg(&pdev->dev, "Remote version = %d\n", val);
+
+ rc = ntb_read_remote_spad(ndev, NUM_QPS, &val);
+ if (rc) {
+ dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_QPS);
+ goto out;
+ }
+
+ if (val != nt->max_qps)
+ goto out;
+ dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val);
+
+ rc = ntb_read_remote_spad(ndev, NUM_MWS, &val);
+ if (rc) {
+ dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_MWS);
+ goto out;
+ }
+
+ if (val != ntb_max_mw(ndev))
+ goto out;
+ dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val);
+
+ for (i = 0; i < ntb_max_mw(ndev); i++) {
+ u64 val64;
+
+ rc = ntb_read_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), &val);
+ if (rc) {
+ dev_err(&pdev->dev, "Error reading remote spad %d\n",
+ MW0_SZ_HIGH + (i * 2));
+ goto out1;
+ }
+
+ val64 = (u64) val << 32;
+
+ rc = ntb_read_remote_spad(ndev, MW0_SZ_LOW + (i * 2), &val);
+ if (rc) {
+ dev_err(&pdev->dev, "Error reading remote spad %d\n",
+ MW0_SZ_LOW + (i * 2));
+ goto out1;
+ }
+
+ val64 |= val;
+
+ dev_dbg(&pdev->dev, "Remote MW%d size = %llu\n", i, val64);
+
+ rc = ntb_set_mw(nt, i, val64);
+ if (rc)
+ goto out1;
+ }
+
+ nt->transport_link = NTB_LINK_UP;
+
+ for (i = 0; i < nt->max_qps; i++) {
+ struct ntb_transport_qp *qp = &nt->qps[i];
+
+ ntb_transport_setup_qp_mw(nt, i);
+
+ if (qp->client_ready == NTB_LINK_UP)
+ schedule_delayed_work(&qp->link_work, 0);
+ }
+
+ return;
+
+out1:
+ for (i = 0; i < ntb_max_mw(ndev); i++)
+ ntb_free_mw(nt, i);
+out:
+ if (ntb_hw_link_status(ndev))
+ schedule_delayed_work(&nt->link_work,
+ msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
+}
+
+static void ntb_qp_link_work(struct work_struct *work)
+{
+ struct ntb_transport_qp *qp = container_of(work,
+ struct ntb_transport_qp,
+ link_work.work);
+ struct pci_dev *pdev = ntb_query_pdev(qp->ndev);
+ struct ntb_transport *nt = qp->transport;
+ int rc, val;
+
+ WARN_ON(nt->transport_link != NTB_LINK_UP);
+
+ rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val);
+ if (rc) {
+ dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS);
+ return;
+ }
+
+ rc = ntb_write_remote_spad(nt->ndev, QP_LINKS, val | 1 << qp->qp_num);
+ if (rc)
+ dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
+ val | 1 << qp->qp_num, QP_LINKS);
+
+ /* query remote spad for qp ready bits */
+ rc = ntb_read_remote_spad(nt->ndev, QP_LINKS, &val);
+ if (rc)
+ dev_err(&pdev->dev, "Error reading remote spad %d\n", QP_LINKS);
+
+ dev_dbg(&pdev->dev, "Remote QP link status = %x\n", val);
+
+ /* See if the remote side is up */
+ if (1 << qp->qp_num & val) {
+ qp->qp_link = NTB_LINK_UP;
+
+ dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num);
+ if (qp->event_handler)
+ qp->event_handler(qp->cb_data, NTB_LINK_UP);
+ } else if (nt->transport_link == NTB_LINK_UP)
+ schedule_delayed_work(&qp->link_work,
+ msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
+}
+
+static int ntb_transport_init_queue(struct ntb_transport *nt,
+ unsigned int qp_num)
+{
+ struct ntb_transport_qp *qp;
+ unsigned int num_qps_mw, tx_size;
+ u8 mw_num, mw_max;
+ u64 qp_offset;
+
+ mw_max = ntb_max_mw(nt->ndev);
+ mw_num = QP_TO_MW(nt->ndev, qp_num);
+
+ qp = &nt->qps[qp_num];
+ qp->qp_num = qp_num;
+ qp->transport = nt;
+ qp->ndev = nt->ndev;
+ qp->qp_link = NTB_LINK_DOWN;
+ qp->client_ready = NTB_LINK_DOWN;
+ qp->event_handler = NULL;
+
+ if (nt->max_qps % mw_max && mw_num + 1 < nt->max_qps / mw_max)
+ num_qps_mw = nt->max_qps / mw_max + 1;
+ else
+ num_qps_mw = nt->max_qps / mw_max;
+
+ tx_size = (unsigned int) ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw;
+ qp_offset = qp_num / mw_max * tx_size;
+ qp->tx_mw = ntb_get_mw_vbase(nt->ndev, mw_num) + qp_offset;
+ if (!qp->tx_mw)
+ return -EINVAL;
+
+ qp->tx_mw_phys = ntb_get_mw_base(qp->ndev, mw_num) + qp_offset;
+ if (!qp->tx_mw_phys)
+ return -EINVAL;
+
+ tx_size -= sizeof(struct ntb_rx_info);
+ qp->rx_info = qp->tx_mw + tx_size;
+
+ /* Due to housekeeping, there must be atleast 2 buffs */
+ qp->tx_max_frame = min(transport_mtu, tx_size / 2);
+ qp->tx_max_entry = tx_size / qp->tx_max_frame;
+
+ if (ntb_query_debugfs(nt->ndev)) {
+ char debugfs_name[4];
+
+ snprintf(debugfs_name, 4, "qp%d", qp_num);
+ qp->debugfs_dir = debugfs_create_dir(debugfs_name,
+ ntb_query_debugfs(nt->ndev));
+
+ qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR,
+ qp->debugfs_dir, qp,
+ &ntb_qp_debugfs_stats);
+ }
+
+ INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work);
+ INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup_work);
+
+ spin_lock_init(&qp->ntb_rx_pend_q_lock);
+ spin_lock_init(&qp->ntb_rx_free_q_lock);
+ spin_lock_init(&qp->ntb_tx_free_q_lock);
+
+ INIT_LIST_HEAD(&qp->rx_pend_q);
+ INIT_LIST_HEAD(&qp->rx_free_q);
+ INIT_LIST_HEAD(&qp->tx_free_q);
+
+ return 0;
+}
+
+int ntb_transport_init(struct pci_dev *pdev)
+{
+ struct ntb_transport *nt;
+ int rc, i;
+
+ nt = kzalloc(sizeof(struct ntb_transport), GFP_KERNEL);
+ if (!nt)
+ return -ENOMEM;
+
+ nt->ndev = ntb_register_transport(pdev, nt);
+ if (!nt->ndev) {
+ rc = -EIO;
+ goto err;
+ }
+
+ nt->mw = kcalloc(ntb_max_mw(nt->ndev), sizeof(struct ntb_transport_mw),
+ GFP_KERNEL);
+ if (!nt->mw) {
+ rc = -ENOMEM;
+ goto err1;
+ }
+
+ if (max_num_clients)
+ nt->max_qps = min(ntb_max_cbs(nt->ndev), max_num_clients);
+ else
+ nt->max_qps = min(ntb_max_cbs(nt->ndev), ntb_max_mw(nt->ndev));
+
+ nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp),
+ GFP_KERNEL);
+ if (!nt->qps) {
+ rc = -ENOMEM;
+ goto err2;
+ }
+
+ nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1;
+
+ for (i = 0; i < nt->max_qps; i++) {
+ rc = ntb_transport_init_queue(nt, i);
+ if (rc)
+ goto err3;
+ }
+
+ INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work);
+ INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup_work);
+
+ rc = ntb_register_event_callback(nt->ndev,
+ ntb_transport_event_callback);
+ if (rc)
+ goto err3;
+
+ INIT_LIST_HEAD(&nt->client_devs);
+ rc = ntb_bus_init(nt);
+ if (rc)
+ goto err4;
+
+ if (ntb_hw_link_status(nt->ndev))
+ schedule_delayed_work(&nt->link_work, 0);
+
+ return 0;
+
+err4:
+ ntb_unregister_event_callback(nt->ndev);
+err3:
+ kfree(nt->qps);
+err2:
+ kfree(nt->mw);
+err1:
+ ntb_unregister_transport(nt->ndev);
+err:
+ kfree(nt);
+ return rc;
+}
+
+void ntb_transport_free(void *transport)
+{
+ struct ntb_transport *nt = transport;
+ struct ntb_device *ndev = nt->ndev;
+ int i;
+
+ ntb_transport_link_cleanup(nt);
+
+ /* verify that all the qp's are freed */
+ for (i = 0; i < nt->max_qps; i++) {
+ if (!test_bit(i, &nt->qp_bitmap))
+ ntb_transport_free_queue(&nt->qps[i]);
+ debugfs_remove_recursive(nt->qps[i].debugfs_dir);
+ }
+
+ ntb_bus_remove(nt);
+
+ cancel_delayed_work_sync(&nt->link_work);
+
+ ntb_unregister_event_callback(ndev);
+
+ for (i = 0; i < ntb_max_mw(ndev); i++)
+ ntb_free_mw(nt, i);
+
+ kfree(nt->qps);
+ kfree(nt->mw);
+ ntb_unregister_transport(ndev);
+ kfree(nt);
+}
+
+static void ntb_rx_copy_callback(void *data)
+{
+ struct ntb_queue_entry *entry = data;
+ struct ntb_transport_qp *qp = entry->qp;
+ void *cb_data = entry->cb_data;
+ unsigned int len = entry->len;
+ struct ntb_payload_header *hdr = entry->rx_hdr;
+
+ /* Ensure that the data is fully copied out before clearing the flag */
+ wmb();
+ hdr->flags = 0;
+
+ iowrite32(entry->index, &qp->rx_info->entry);
+
+ ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q);
+
+ if (qp->rx_handler && qp->client_ready == NTB_LINK_UP)
+ qp->rx_handler(qp, qp->cb_data, cb_data, len);
+}
+
+static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset)
+{
+ void *buf = entry->buf;
+ size_t len = entry->len;
+
+ memcpy(buf, offset, len);
+
+ ntb_rx_copy_callback(entry);
+}
+
+static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset,
+ size_t len)
+{
+ struct dma_async_tx_descriptor *txd;
+ struct ntb_transport_qp *qp = entry->qp;
+ struct dma_chan *chan = qp->dma_chan;
+ struct dma_device *device;
+ size_t pay_off, buff_off;
+ struct dmaengine_unmap_data *unmap;
+ dma_cookie_t cookie;
+ void *buf = entry->buf;
+
+ entry->len = len;
+
+ if (!chan)
+ goto err;
+
+ if (len < copy_bytes)
+ goto err_wait;
+
+ device = chan->device;
+ pay_off = (size_t) offset & ~PAGE_MASK;
+ buff_off = (size_t) buf & ~PAGE_MASK;
+
+ if (!is_dma_copy_aligned(device, pay_off, buff_off, len))
+ goto err_wait;
+
+ unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT);
+ if (!unmap)
+ goto err_wait;
+
+ unmap->len = len;
+ unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset),
+ pay_off, len, DMA_TO_DEVICE);
+ if (dma_mapping_error(device->dev, unmap->addr[0]))
+ goto err_get_unmap;
+
+ unmap->to_cnt = 1;
+
+ unmap->addr[1] = dma_map_page(device->dev, virt_to_page(buf),
+ buff_off, len, DMA_FROM_DEVICE);
+ if (dma_mapping_error(device->dev, unmap->addr[1]))
+ goto err_get_unmap;
+
+ unmap->from_cnt = 1;
+
+ txd = device->device_prep_dma_memcpy(chan, unmap->addr[1],
+ unmap->addr[0], len,
+ DMA_PREP_INTERRUPT);
+ if (!txd)
+ goto err_get_unmap;
+
+ txd->callback = ntb_rx_copy_callback;
+ txd->callback_param = entry;
+ dma_set_unmap(txd, unmap);
+
+ cookie = dmaengine_submit(txd);
+ if (dma_submit_error(cookie))
+ goto err_set_unmap;
+
+ dmaengine_unmap_put(unmap);
+
+ qp->last_cookie = cookie;
+
+ qp->rx_async++;
+
+ return;
+
+err_set_unmap:
+ dmaengine_unmap_put(unmap);
+err_get_unmap:
+ dmaengine_unmap_put(unmap);
+err_wait:
+ /* If the callbacks come out of order, the writing of the index to the
+ * last completed will be out of order. This may result in the
+ * receive stalling forever.
+ */
+ dma_sync_wait(chan, qp->last_cookie);
+err:
+ ntb_memcpy_rx(entry, offset);
+ qp->rx_memcpy++;
+}
+
+static int ntb_process_rxc(struct ntb_transport_qp *qp)
+{
+ struct ntb_payload_header *hdr;
+ struct ntb_queue_entry *entry;
+ void *offset;
+
+ offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index;
+ hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header);
+
+ entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q);
+ if (!entry) {
+ dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
+ "no buffer - HDR ver %u, len %d, flags %x\n",
+ hdr->ver, hdr->len, hdr->flags);
+ qp->rx_err_no_buf++;
+ return -ENOMEM;
+ }
+
+ if (!(hdr->flags & DESC_DONE_FLAG)) {
+ ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
+ &qp->rx_pend_q);
+ qp->rx_ring_empty++;
+ return -EAGAIN;
+ }
+
+ if (hdr->ver != (u32) qp->rx_pkts) {
+ dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
+ "qp %d: version mismatch, expected %llu - got %u\n",
+ qp->qp_num, qp->rx_pkts, hdr->ver);
+ ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
+ &qp->rx_pend_q);
+ qp->rx_err_ver++;
+ return -EIO;
+ }
+
+ if (hdr->flags & LINK_DOWN_FLAG) {
+ ntb_qp_link_down(qp);
+
+ goto err;
+ }
+
+ dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
+ "rx offset %u, ver %u - %d payload received, buf size %d\n",
+ qp->rx_index, hdr->ver, hdr->len, entry->len);
+
+ qp->rx_bytes += hdr->len;
+ qp->rx_pkts++;
+
+ if (hdr->len > entry->len) {
+ qp->rx_err_oflow++;
+ dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
+ "RX overflow! Wanted %d got %d\n",
+ hdr->len, entry->len);
+
+ goto err;
+ }
+
+ entry->index = qp->rx_index;
+ entry->rx_hdr = hdr;
+
+ ntb_async_rx(entry, offset, hdr->len);
+
+out:
+ qp->rx_index++;
+ qp->rx_index %= qp->rx_max_entry;
+
+ return 0;
+
+err:
+ ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q);
+ /* Ensure that the data is fully copied out before clearing the flag */
+ wmb();
+ hdr->flags = 0;
+ iowrite32(qp->rx_index, &qp->rx_info->entry);
+
+ goto out;
+}
+
+static int ntb_transport_rxc_db(void *data, int db_num)
+{
+ struct ntb_transport_qp *qp = data;
+ int rc, i;
+
+ dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n",
+ __func__, db_num);
+
+ /* Limit the number of packets processed in a single interrupt to
+ * provide fairness to others
+ */
+ for (i = 0; i < qp->rx_max_entry; i++) {
+ rc = ntb_process_rxc(qp);
+ if (rc)
+ break;
+ }
+
+ if (qp->dma_chan)
+ dma_async_issue_pending(qp->dma_chan);
+
+ return i;
+}
+
+static void ntb_tx_copy_callback(void *data)
+{
+ struct ntb_queue_entry *entry = data;
+ struct ntb_transport_qp *qp = entry->qp;
+ struct ntb_payload_header __iomem *hdr = entry->tx_hdr;
+
+ /* Ensure that the data is fully copied out before setting the flags */
+ wmb();
+ iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags);
+
+ ntb_ring_doorbell(qp->ndev, qp->qp_num);
+
+ /* The entry length can only be zero if the packet is intended to be a
+ * "link down" or similar. Since no payload is being sent in these
+ * cases, there is nothing to add to the completion queue.
+ */
+ if (entry->len > 0) {
+ qp->tx_bytes += entry->len;
+
+ if (qp->tx_handler)
+ qp->tx_handler(qp, qp->cb_data, entry->cb_data,
+ entry->len);
+ }
+
+ ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q);
+}
+
+static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset)
+{
+ memcpy_toio(offset, entry->buf, entry->len);
+
+ ntb_tx_copy_callback(entry);
+}
+
+static void ntb_async_tx(struct ntb_transport_qp *qp,
+ struct ntb_queue_entry *entry)
+{
+ struct ntb_payload_header __iomem *hdr;
+ struct dma_async_tx_descriptor *txd;
+ struct dma_chan *chan = qp->dma_chan;
+ struct dma_device *device;
+ size_t dest_off, buff_off;
+ struct dmaengine_unmap_data *unmap;
+ dma_addr_t dest;
+ dma_cookie_t cookie;
+ void __iomem *offset;
+ size_t len = entry->len;
+ void *buf = entry->buf;
+
+ offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index;
+ hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header);
+ entry->tx_hdr = hdr;
+
+ iowrite32(entry->len, &hdr->len);
+ iowrite32((u32) qp->tx_pkts, &hdr->ver);
+
+ if (!chan)
+ goto err;
+
+ if (len < copy_bytes)
+ goto err;
+
+ device = chan->device;
+ dest = qp->tx_mw_phys + qp->tx_max_frame * qp->tx_index;
+ buff_off = (size_t) buf & ~PAGE_MASK;
+ dest_off = (size_t) dest & ~PAGE_MASK;
+
+ if (!is_dma_copy_aligned(device, buff_off, dest_off, len))
+ goto err;
+
+ unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT);
+ if (!unmap)
+ goto err;
+
+ unmap->len = len;
+ unmap->addr[0] = dma_map_page(device->dev, virt_to_page(buf),
+ buff_off, len, DMA_TO_DEVICE);
+ if (dma_mapping_error(device->dev, unmap->addr[0]))
+ goto err_get_unmap;
+
+ unmap->to_cnt = 1;
+
+ txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], len,
+ DMA_PREP_INTERRUPT);
+ if (!txd)
+ goto err_get_unmap;
+
+ txd->callback = ntb_tx_copy_callback;
+ txd->callback_param = entry;
+ dma_set_unmap(txd, unmap);
+
+ cookie = dmaengine_submit(txd);
+ if (dma_submit_error(cookie))
+ goto err_set_unmap;
+
+ dmaengine_unmap_put(unmap);
+
+ dma_async_issue_pending(chan);
+ qp->tx_async++;
+
+ return;
+err_set_unmap:
+ dmaengine_unmap_put(unmap);
+err_get_unmap:
+ dmaengine_unmap_put(unmap);
+err:
+ ntb_memcpy_tx(entry, offset);
+ qp->tx_memcpy++;
+}
+
+static int ntb_process_tx(struct ntb_transport_qp *qp,
+ struct ntb_queue_entry *entry)
+{
+ dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - tx %u, entry len %d flags %x buff %p\n",
+ qp->tx_pkts, qp->tx_index, entry->len, entry->flags,
+ entry->buf);
+ if (qp->tx_index == qp->remote_rx_info->entry) {
+ qp->tx_ring_full++;
+ return -EAGAIN;
+ }
+
+ if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) {
+ if (qp->tx_handler)
+ qp->tx_handler(qp->cb_data, qp, NULL, -EIO);
+
+ ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
+ &qp->tx_free_q);
+ return 0;
+ }
+
+ ntb_async_tx(qp, entry);
+
+ qp->tx_index++;
+ qp->tx_index %= qp->tx_max_entry;
+
+ qp->tx_pkts++;
+
+ return 0;
+}
+
+static void ntb_send_link_down(struct ntb_transport_qp *qp)
+{
+ struct pci_dev *pdev = ntb_query_pdev(qp->ndev);
+ struct ntb_queue_entry *entry;
+ int i, rc;
+
+ if (qp->qp_link == NTB_LINK_DOWN)
+ return;
+
+ qp->qp_link = NTB_LINK_DOWN;
+ dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num);
+
+ for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) {
+ entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q);
+ if (entry)
+ break;
+ msleep(100);
+ }
+
+ if (!entry)
+ return;
+
+ entry->cb_data = NULL;
+ entry->buf = NULL;
+ entry->len = 0;
+ entry->flags = LINK_DOWN_FLAG;
+
+ rc = ntb_process_tx(qp, entry);
+ if (rc)
+ dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n",
+ qp->qp_num);
+}
+
+/**
+ * ntb_transport_create_queue - Create a new NTB transport layer queue
+ * @rx_handler: receive callback function
+ * @tx_handler: transmit callback function
+ * @event_handler: event callback function
+ *
+ * Create a new NTB transport layer queue and provide the queue with a callback
+ * routine for both transmit and receive. The receive callback routine will be
+ * used to pass up data when the transport has received it on the queue. The
+ * transmit callback routine will be called when the transport has completed the
+ * transmission of the data on the queue and the data is ready to be freed.
+ *
+ * RETURNS: pointer to newly created ntb_queue, NULL on error.
+ */
+struct ntb_transport_qp *
+ntb_transport_create_queue(void *data, struct pci_dev *pdev,
+ const struct ntb_queue_handlers *handlers)
+{
+ struct ntb_queue_entry *entry;
+ struct ntb_transport_qp *qp;
+ struct ntb_transport *nt;
+ unsigned int free_queue;
+ int rc, i;
+
+ nt = ntb_find_transport(pdev);
+ if (!nt)
+ goto err;
+
+ free_queue = ffs(nt->qp_bitmap);
+ if (!free_queue)
+ goto err;
+
+ /* decrement free_queue to make it zero based */
+ free_queue--;
+
+ clear_bit(free_queue, &nt->qp_bitmap);
+
+ qp = &nt->qps[free_queue];
+ qp->cb_data = data;
+ qp->rx_handler = handlers->rx_handler;
+ qp->tx_handler = handlers->tx_handler;
+ qp->event_handler = handlers->event_handler;
+
+ dmaengine_get();
+ qp->dma_chan = dma_find_channel(DMA_MEMCPY);
+ if (!qp->dma_chan) {
+ dmaengine_put();
+ dev_info(&pdev->dev, "Unable to allocate DMA channel, using CPU instead\n");
+ }
+
+ for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
+ entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC);
+ if (!entry)
+ goto err1;
+
+ entry->qp = qp;
+ ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry,
+ &qp->rx_free_q);
+ }
+
+ for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
+ entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC);
+ if (!entry)
+ goto err2;
+
+ entry->qp = qp;
+ ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
+ &qp->tx_free_q);
+ }
+
+ rc = ntb_register_db_callback(qp->ndev, free_queue, qp,
+ ntb_transport_rxc_db);
+ if (rc)
+ goto err2;
+
+ dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num);
+
+ return qp;
+
+err2:
+ while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q)))
+ kfree(entry);
+err1:
+ while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q)))
+ kfree(entry);
+ if (qp->dma_chan)
+ dmaengine_put();
+ set_bit(free_queue, &nt->qp_bitmap);
+err:
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(ntb_transport_create_queue);
+
+/**
+ * ntb_transport_free_queue - Frees NTB transport queue
+ * @qp: NTB queue to be freed
+ *
+ * Frees NTB transport queue
+ */
+void ntb_transport_free_queue(struct ntb_transport_qp *qp)
+{
+ struct pci_dev *pdev;
+ struct ntb_queue_entry *entry;
+
+ if (!qp)
+ return;
+
+ pdev = ntb_query_pdev(qp->ndev);
+
+ if (qp->dma_chan) {
+ struct dma_chan *chan = qp->dma_chan;
+ /* Putting the dma_chan to NULL will force any new traffic to be
+ * processed by the CPU instead of the DAM engine
+ */
+ qp->dma_chan = NULL;
+
+ /* Try to be nice and wait for any queued DMA engine
+ * transactions to process before smashing it with a rock
+ */
+ dma_sync_wait(chan, qp->last_cookie);
+ dmaengine_terminate_all(chan);
+ dmaengine_put();
+ }
+
+ ntb_unregister_db_callback(qp->ndev, qp->qp_num);
+
+ cancel_delayed_work_sync(&qp->link_work);
+
+ while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q)))
+ kfree(entry);
+
+ while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) {
+ dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n");
+ kfree(entry);
+ }
+
+ while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q)))
+ kfree(entry);
+
+ set_bit(qp->qp_num, &qp->transport->qp_bitmap);
+
+ dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num);
+}
+EXPORT_SYMBOL_GPL(ntb_transport_free_queue);
+
+/**
+ * ntb_transport_rx_remove - Dequeues enqueued rx packet
+ * @qp: NTB queue to be freed
+ * @len: pointer to variable to write enqueued buffers length
+ *
+ * Dequeues unused buffers from receive queue. Should only be used during
+ * shutdown of qp.
+ *
+ * RETURNS: NULL error value on error, or void* for success.
+ */
+void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len)
+{
+ struct ntb_queue_entry *entry;
+ void *buf;
+
+ if (!qp || qp->client_ready == NTB_LINK_UP)
+ return NULL;
+
+ entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q);
+ if (!entry)
+ return NULL;
+
+ buf = entry->cb_data;
+ *len = entry->len;
+
+ ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q);
+
+ return buf;
+}
+EXPORT_SYMBOL_GPL(ntb_transport_rx_remove);
+
+/**
+ * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry
+ * @qp: NTB transport layer queue the entry is to be enqueued on
+ * @cb: per buffer pointer for callback function to use
+ * @data: pointer to data buffer that incoming packets will be copied into
+ * @len: length of the data buffer
+ *
+ * Enqueue a new receive buffer onto the transport queue into which a NTB
+ * payload can be received into.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data,
+ unsigned int len)
+{
+ struct ntb_queue_entry *entry;
+
+ if (!qp)
+ return -EINVAL;
+
+ entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->cb_data = cb;
+ entry->buf = data;
+ entry->len = len;
+
+ ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue);
+
+/**
+ * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry
+ * @qp: NTB transport layer queue the entry is to be enqueued on
+ * @cb: per buffer pointer for callback function to use
+ * @data: pointer to data buffer that will be sent
+ * @len: length of the data buffer
+ *
+ * Enqueue a new transmit buffer onto the transport queue from which a NTB
+ * payload will be transmitted. This assumes that a lock is being held to
+ * serialize access to the qp.
+ *
+ * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
+ */
+int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data,
+ unsigned int len)
+{
+ struct ntb_queue_entry *entry;
+ int rc;
+
+ if (!qp || qp->qp_link != NTB_LINK_UP || !len)
+ return -EINVAL;
+
+ entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q);
+ if (!entry) {
+ qp->tx_err_no_buf++;
+ return -ENOMEM;
+ }
+
+ entry->cb_data = cb;
+ entry->buf = data;
+ entry->len = len;
+ entry->flags = 0;
+
+ rc = ntb_process_tx(qp, entry);
+ if (rc)
+ ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
+ &qp->tx_free_q);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue);
+
+/**
+ * ntb_transport_link_up - Notify NTB transport of client readiness to use queue
+ * @qp: NTB transport layer queue to be enabled
+ *
+ * Notify NTB transport layer of client readiness to use queue
+ */
+void ntb_transport_link_up(struct ntb_transport_qp *qp)
+{
+ if (!qp)
+ return;
+
+ qp->client_ready = NTB_LINK_UP;
+
+ if (qp->transport->transport_link == NTB_LINK_UP)
+ schedule_delayed_work(&qp->link_work, 0);
+}
+EXPORT_SYMBOL_GPL(ntb_transport_link_up);
+
+/**
+ * ntb_transport_link_down - Notify NTB transport to no longer enqueue data
+ * @qp: NTB transport layer queue to be disabled
+ *
+ * Notify NTB transport layer of client's desire to no longer receive data on
+ * transport queue specified. It is the client's responsibility to ensure all
+ * entries on queue are purged or otherwise handled appropriately.
+ */
+void ntb_transport_link_down(struct ntb_transport_qp *qp)
+{
+ struct pci_dev *pdev;
+ int rc, val;
+
+ if (!qp)
+ return;
+
+ pdev = ntb_query_pdev(qp->ndev);
+ qp->client_ready = NTB_LINK_DOWN;
+
+ rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val);
+ if (rc) {
+ dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS);
+ return;
+ }
+
+ rc = ntb_write_remote_spad(qp->ndev, QP_LINKS,
+ val & ~(1 << qp->qp_num));
+ if (rc)
+ dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
+ val & ~(1 << qp->qp_num), QP_LINKS);
+
+ if (qp->qp_link == NTB_LINK_UP)
+ ntb_send_link_down(qp);
+ else
+ cancel_delayed_work_sync(&qp->link_work);
+}
+EXPORT_SYMBOL_GPL(ntb_transport_link_down);
+
+/**
+ * ntb_transport_link_query - Query transport link state
+ * @qp: NTB transport layer queue to be queried
+ *
+ * Query connectivity to the remote system of the NTB transport queue
+ *
+ * RETURNS: true for link up or false for link down
+ */
+bool ntb_transport_link_query(struct ntb_transport_qp *qp)
+{
+ if (!qp)
+ return false;
+
+ return qp->qp_link == NTB_LINK_UP;
+}
+EXPORT_SYMBOL_GPL(ntb_transport_link_query);
+
+/**
+ * ntb_transport_qp_num - Query the qp number
+ * @qp: NTB transport layer queue to be queried
+ *
+ * Query qp number of the NTB transport queue
+ *
+ * RETURNS: a zero based number specifying the qp number
+ */
+unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp)
+{
+ if (!qp)
+ return 0;
+
+ return qp->qp_num;
+}
+EXPORT_SYMBOL_GPL(ntb_transport_qp_num);
+
+/**
+ * ntb_transport_max_size - Query the max payload size of a qp
+ * @qp: NTB transport layer queue to be queried
+ *
+ * Query the maximum payload size permissible on the given qp
+ *
+ * RETURNS: the max payload size of a qp
+ */
+unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp)
+{
+ unsigned int max;
+
+ if (!qp)
+ return 0;
+
+ if (!qp->dma_chan)
+ return qp->tx_max_frame - sizeof(struct ntb_payload_header);
+
+ /* If DMA engine usage is possible, try to find the max size for that */
+ max = qp->tx_max_frame - sizeof(struct ntb_payload_header);
+ max -= max % (1 << qp->dma_chan->device->copy_align);
+
+ return max;
+}
+EXPORT_SYMBOL_GPL(ntb_transport_max_size);