diff options
Diffstat (limited to 'kernel/drivers/pci/host/pcie-iproc.c')
-rw-r--r-- | kernel/drivers/pci/host/pcie-iproc.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/kernel/drivers/pci/host/pcie-iproc.c b/kernel/drivers/pci/host/pcie-iproc.c new file mode 100644 index 000000000..329e1b545 --- /dev/null +++ b/kernel/drivers/pci/host/pcie-iproc.c @@ -0,0 +1,268 @@ +/* + * Copyright (C) 2014 Hauke Mehrtens <hauke@hauke-m.de> + * Copyright (C) 2015 Broadcom Corporatcommon ion + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/pci.h> +#include <linux/msi.h> +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/mbus.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/of_address.h> +#include <linux/of_pci.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/phy/phy.h> + +#include "pcie-iproc.h" + +#define CLK_CONTROL_OFFSET 0x000 +#define EP_MODE_SURVIVE_PERST_SHIFT 1 +#define EP_MODE_SURVIVE_PERST BIT(EP_MODE_SURVIVE_PERST_SHIFT) +#define RC_PCIE_RST_OUTPUT_SHIFT 0 +#define RC_PCIE_RST_OUTPUT BIT(RC_PCIE_RST_OUTPUT_SHIFT) + +#define CFG_IND_ADDR_OFFSET 0x120 +#define CFG_IND_ADDR_MASK 0x00001ffc + +#define CFG_IND_DATA_OFFSET 0x124 + +#define CFG_ADDR_OFFSET 0x1f8 +#define CFG_ADDR_BUS_NUM_SHIFT 20 +#define CFG_ADDR_BUS_NUM_MASK 0x0ff00000 +#define CFG_ADDR_DEV_NUM_SHIFT 15 +#define CFG_ADDR_DEV_NUM_MASK 0x000f8000 +#define CFG_ADDR_FUNC_NUM_SHIFT 12 +#define CFG_ADDR_FUNC_NUM_MASK 0x00007000 +#define CFG_ADDR_REG_NUM_SHIFT 2 +#define CFG_ADDR_REG_NUM_MASK 0x00000ffc +#define CFG_ADDR_CFG_TYPE_SHIFT 0 +#define CFG_ADDR_CFG_TYPE_MASK 0x00000003 + +#define CFG_DATA_OFFSET 0x1fc + +#define SYS_RC_INTX_EN 0x330 +#define SYS_RC_INTX_MASK 0xf + +static inline struct iproc_pcie *sys_to_pcie(struct pci_sys_data *sys) +{ + return sys->private_data; +} + +/** + * Note access to the configuration registers are protected at the higher layer + * by 'pci_lock' in drivers/pci/access.c + */ +static void __iomem *iproc_pcie_map_cfg_bus(struct pci_bus *bus, + unsigned int devfn, + int where) +{ + struct pci_sys_data *sys = bus->sysdata; + struct iproc_pcie *pcie = sys_to_pcie(sys); + unsigned slot = PCI_SLOT(devfn); + unsigned fn = PCI_FUNC(devfn); + unsigned busno = bus->number; + u32 val; + + /* root complex access */ + if (busno == 0) { + if (slot >= 1) + return NULL; + writel(where & CFG_IND_ADDR_MASK, + pcie->base + CFG_IND_ADDR_OFFSET); + return (pcie->base + CFG_IND_DATA_OFFSET); + } + + if (fn > 1) + return NULL; + + /* EP device access */ + val = (busno << CFG_ADDR_BUS_NUM_SHIFT) | + (slot << CFG_ADDR_DEV_NUM_SHIFT) | + (fn << CFG_ADDR_FUNC_NUM_SHIFT) | + (where & CFG_ADDR_REG_NUM_MASK) | + (1 & CFG_ADDR_CFG_TYPE_MASK); + writel(val, pcie->base + CFG_ADDR_OFFSET); + + return (pcie->base + CFG_DATA_OFFSET); +} + +static struct pci_ops iproc_pcie_ops = { + .map_bus = iproc_pcie_map_cfg_bus, + .read = pci_generic_config_read32, + .write = pci_generic_config_write32, +}; + +static void iproc_pcie_reset(struct iproc_pcie *pcie) +{ + u32 val; + + /* + * Configure the PCIe controller as root complex and send a downstream + * reset + */ + val = EP_MODE_SURVIVE_PERST | RC_PCIE_RST_OUTPUT; + writel(val, pcie->base + CLK_CONTROL_OFFSET); + udelay(250); + val &= ~EP_MODE_SURVIVE_PERST; + writel(val, pcie->base + CLK_CONTROL_OFFSET); + msleep(250); +} + +static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus) +{ + u8 hdr_type; + u32 link_ctrl; + u16 pos, link_status; + int link_is_active = 0; + + /* make sure we are not in EP mode */ + pci_bus_read_config_byte(bus, 0, PCI_HEADER_TYPE, &hdr_type); + if ((hdr_type & 0x7f) != PCI_HEADER_TYPE_BRIDGE) { + dev_err(pcie->dev, "in EP mode, hdr=%#02x\n", hdr_type); + return -EFAULT; + } + + /* force class to PCI_CLASS_BRIDGE_PCI (0x0604) */ + pci_bus_write_config_word(bus, 0, PCI_CLASS_DEVICE, + PCI_CLASS_BRIDGE_PCI); + + /* check link status to see if link is active */ + pos = pci_bus_find_capability(bus, 0, PCI_CAP_ID_EXP); + pci_bus_read_config_word(bus, 0, pos + PCI_EXP_LNKSTA, &link_status); + if (link_status & PCI_EXP_LNKSTA_NLW) + link_is_active = 1; + + if (!link_is_active) { + /* try GEN 1 link speed */ +#define PCI_LINK_STATUS_CTRL_2_OFFSET 0x0dc +#define PCI_TARGET_LINK_SPEED_MASK 0xf +#define PCI_TARGET_LINK_SPEED_GEN2 0x2 +#define PCI_TARGET_LINK_SPEED_GEN1 0x1 + pci_bus_read_config_dword(bus, 0, + PCI_LINK_STATUS_CTRL_2_OFFSET, + &link_ctrl); + if ((link_ctrl & PCI_TARGET_LINK_SPEED_MASK) == + PCI_TARGET_LINK_SPEED_GEN2) { + link_ctrl &= ~PCI_TARGET_LINK_SPEED_MASK; + link_ctrl |= PCI_TARGET_LINK_SPEED_GEN1; + pci_bus_write_config_dword(bus, 0, + PCI_LINK_STATUS_CTRL_2_OFFSET, + link_ctrl); + msleep(100); + + pos = pci_bus_find_capability(bus, 0, PCI_CAP_ID_EXP); + pci_bus_read_config_word(bus, 0, pos + PCI_EXP_LNKSTA, + &link_status); + if (link_status & PCI_EXP_LNKSTA_NLW) + link_is_active = 1; + } + } + + dev_info(pcie->dev, "link: %s\n", link_is_active ? "UP" : "DOWN"); + + return link_is_active ? 0 : -ENODEV; +} + +static void iproc_pcie_enable(struct iproc_pcie *pcie) +{ + writel(SYS_RC_INTX_MASK, pcie->base + SYS_RC_INTX_EN); +} + +int iproc_pcie_setup(struct iproc_pcie *pcie) +{ + int ret; + struct pci_bus *bus; + + if (!pcie || !pcie->dev || !pcie->base) + return -EINVAL; + + if (pcie->phy) { + ret = phy_init(pcie->phy); + if (ret) { + dev_err(pcie->dev, "unable to initialize PCIe PHY\n"); + return ret; + } + + ret = phy_power_on(pcie->phy); + if (ret) { + dev_err(pcie->dev, "unable to power on PCIe PHY\n"); + goto err_exit_phy; + } + + } + + iproc_pcie_reset(pcie); + + pcie->sysdata.private_data = pcie; + + bus = pci_create_root_bus(pcie->dev, 0, &iproc_pcie_ops, + &pcie->sysdata, pcie->resources); + if (!bus) { + dev_err(pcie->dev, "unable to create PCI root bus\n"); + ret = -ENOMEM; + goto err_power_off_phy; + } + pcie->root_bus = bus; + + ret = iproc_pcie_check_link(pcie, bus); + if (ret) { + dev_err(pcie->dev, "no PCIe EP device detected\n"); + goto err_rm_root_bus; + } + + iproc_pcie_enable(pcie); + + pci_scan_child_bus(bus); + pci_assign_unassigned_bus_resources(bus); + pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci); + pci_bus_add_devices(bus); + + return 0; + +err_rm_root_bus: + pci_stop_root_bus(bus); + pci_remove_root_bus(bus); + +err_power_off_phy: + if (pcie->phy) + phy_power_off(pcie->phy); +err_exit_phy: + if (pcie->phy) + phy_exit(pcie->phy); + + return ret; +} +EXPORT_SYMBOL(iproc_pcie_setup); + +int iproc_pcie_remove(struct iproc_pcie *pcie) +{ + pci_stop_root_bus(pcie->root_bus); + pci_remove_root_bus(pcie->root_bus); + + if (pcie->phy) { + phy_power_off(pcie->phy); + phy_exit(pcie->phy); + } + + return 0; +} +EXPORT_SYMBOL(iproc_pcie_remove); + +MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>"); +MODULE_DESCRIPTION("Broadcom iPROC PCIe common driver"); +MODULE_LICENSE("GPL v2"); |