Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 366 insertions, 0 deletions

diff --git a/kernel/drivers/iommu/irq_remapping.c b/kernel/drivers/iommu/irq_remapping.c
new file mode 100644
index 000000000..390079ee1
--- /dev/null
+++ b/kernel/drivers/iommu/irq_remapping.c
@@ -0,0 +1,366 @@
+#include <linux/seq_file.h>
+#include <linux/cpumask.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/msi.h>
+#include <linux/irq.h>
+#include <linux/pci.h>
+
+#include <asm/hw_irq.h>
+#include <asm/irq_remapping.h>
+#include <asm/processor.h>
+#include <asm/x86_init.h>
+#include <asm/apic.h>
+#include <asm/hpet.h>
+
+#include "irq_remapping.h"
+
+int irq_remapping_enabled;
+int irq_remap_broken;
+int disable_sourceid_checking;
+int no_x2apic_optout;
+
+static int disable_irq_remap;
+static struct irq_remap_ops *remap_ops;
+
+static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec);
+static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
+				  int index, int sub_handle);
+static int set_remapped_irq_affinity(struct irq_data *data,
+				     const struct cpumask *mask,
+				     bool force);
+
+static bool irq_remapped(struct irq_cfg *cfg)
+{
+	return (cfg->remapped == 1);
+}
+
+static void irq_remapping_disable_io_apic(void)
+{
+	/*
+	 * With interrupt-remapping, for now we will use virtual wire A
+	 * mode, as virtual wire B is little complex (need to configure
+	 * both IOAPIC RTE as well as interrupt-remapping table entry).
+	 * As this gets called during crash dump, keep this simple for
+	 * now.
+	 */
+	if (cpu_has_apic || apic_from_smp_config())
+		disconnect_bsp_APIC(0);
+}
+
+static int do_setup_msi_irqs(struct pci_dev *dev, int nvec)
+{
+	int ret, sub_handle, nvec_pow2, index = 0;
+	unsigned int irq;
+	struct msi_desc *msidesc;
+
+	msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
+
+	irq = irq_alloc_hwirqs(nvec, dev_to_node(&dev->dev));
+	if (irq == 0)
+		return -ENOSPC;
+
+	nvec_pow2 = __roundup_pow_of_two(nvec);
+	for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
+		if (!sub_handle) {
+			index = msi_alloc_remapped_irq(dev, irq, nvec_pow2);
+			if (index < 0) {
+				ret = index;
+				goto error;
+			}
+		} else {
+			ret = msi_setup_remapped_irq(dev, irq + sub_handle,
+						     index, sub_handle);
+			if (ret < 0)
+				goto error;
+		}
+		ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
+		if (ret < 0)
+			goto error;
+	}
+	return 0;
+
+error:
+	irq_free_hwirqs(irq, nvec);
+
+	/*
+	 * Restore altered MSI descriptor fields and prevent just destroyed
+	 * IRQs from tearing down again in default_teardown_msi_irqs()
+	 */
+	msidesc->irq = 0;
+
+	return ret;
+}
+
+static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
+{
+	int node, ret, sub_handle, index = 0;
+	struct msi_desc *msidesc;
+	unsigned int irq;
+
+	node		= dev_to_node(&dev->dev);
+	sub_handle	= 0;
+
+	list_for_each_entry(msidesc, &dev->msi_list, list) {
+
+		irq = irq_alloc_hwirq(node);
+		if (irq == 0)
+			return -1;
+
+		if (sub_handle == 0)
+			ret = index = msi_alloc_remapped_irq(dev, irq, nvec);
+		else
+			ret = msi_setup_remapped_irq(dev, irq, index, sub_handle);
+
+		if (ret < 0)
+			goto error;
+
+		ret = setup_msi_irq(dev, msidesc, irq, 0);
+		if (ret < 0)
+			goto error;
+
+		sub_handle += 1;
+		irq        += 1;
+	}
+
+	return 0;
+
+error:
+	irq_free_hwirq(irq);
+	return ret;
+}
+
+static int irq_remapping_setup_msi_irqs(struct pci_dev *dev,
+					int nvec, int type)
+{
+	if (type == PCI_CAP_ID_MSI)
+		return do_setup_msi_irqs(dev, nvec);
+	else
+		return do_setup_msix_irqs(dev, nvec);
+}
+
+static void eoi_ioapic_pin_remapped(int apic, int pin, int vector)
+{
+	/*
+	 * Intr-remapping uses pin number as the virtual vector
+	 * in the RTE. Actual vector is programmed in
+	 * intr-remapping table entry. Hence for the io-apic
+	 * EOI we use the pin number.
+	 */
+	io_apic_eoi(apic, pin);
+}
+
+static void __init irq_remapping_modify_x86_ops(void)
+{
+	x86_io_apic_ops.disable		= irq_remapping_disable_io_apic;
+	x86_io_apic_ops.set_affinity	= set_remapped_irq_affinity;
+	x86_io_apic_ops.setup_entry	= setup_ioapic_remapped_entry;
+	x86_io_apic_ops.eoi_ioapic_pin	= eoi_ioapic_pin_remapped;
+	x86_msi.setup_msi_irqs		= irq_remapping_setup_msi_irqs;
+	x86_msi.setup_hpet_msi		= setup_hpet_msi_remapped;
+	x86_msi.compose_msi_msg		= compose_remapped_msi_msg;
+}
+
+static __init int setup_nointremap(char *str)
+{
+	disable_irq_remap = 1;
+	return 0;
+}
+early_param("nointremap", setup_nointremap);
+
+static __init int setup_irqremap(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	while (*str) {
+		if (!strncmp(str, "on", 2))
+			disable_irq_remap = 0;
+		else if (!strncmp(str, "off", 3))
+			disable_irq_remap = 1;
+		else if (!strncmp(str, "nosid", 5))
+			disable_sourceid_checking = 1;
+		else if (!strncmp(str, "no_x2apic_optout", 16))
+			no_x2apic_optout = 1;
+
+		str += strcspn(str, ",");
+		while (*str == ',')
+			str++;
+	}
+
+	return 0;
+}
+early_param("intremap", setup_irqremap);
+
+void set_irq_remapping_broken(void)
+{
+	irq_remap_broken = 1;
+}
+
+int __init irq_remapping_prepare(void)
+{
+	if (disable_irq_remap)
+		return -ENOSYS;
+
+	if (intel_irq_remap_ops.prepare() == 0)
+		remap_ops = &intel_irq_remap_ops;
+	else if (IS_ENABLED(CONFIG_AMD_IOMMU) &&
+		 amd_iommu_irq_ops.prepare() == 0)
+		remap_ops = &amd_iommu_irq_ops;
+	else
+		return -ENOSYS;
+
+	return 0;
+}
+
+int __init irq_remapping_enable(void)
+{
+	int ret;
+
+	if (!remap_ops->enable)
+		return -ENODEV;
+
+	ret = remap_ops->enable();
+
+	if (irq_remapping_enabled)
+		irq_remapping_modify_x86_ops();
+
+	return ret;
+}
+
+void irq_remapping_disable(void)
+{
+	if (irq_remapping_enabled && remap_ops->disable)
+		remap_ops->disable();
+}
+
+int irq_remapping_reenable(int mode)
+{
+	if (irq_remapping_enabled && remap_ops->reenable)
+		return remap_ops->reenable(mode);
+
+	return 0;
+}
+
+int __init irq_remap_enable_fault_handling(void)
+{
+	if (!irq_remapping_enabled)
+		return 0;
+
+	if (!remap_ops->enable_faulting)
+		return -ENODEV;
+
+	return remap_ops->enable_faulting();
+}
+
+int setup_ioapic_remapped_entry(int irq,
+				struct IO_APIC_route_entry *entry,
+				unsigned int destination, int vector,
+				struct io_apic_irq_attr *attr)
+{
+	if (!remap_ops->setup_ioapic_entry)
+		return -ENODEV;
+
+	return remap_ops->setup_ioapic_entry(irq, entry, destination,
+					     vector, attr);
+}
+
+static int set_remapped_irq_affinity(struct irq_data *data,
+				     const struct cpumask *mask, bool force)
+{
+	if (!config_enabled(CONFIG_SMP) || !remap_ops->set_affinity)
+		return 0;
+
+	return remap_ops->set_affinity(data, mask, force);
+}
+
+void free_remapped_irq(int irq)
+{
+	struct irq_cfg *cfg = irq_cfg(irq);
+
+	if (irq_remapped(cfg) && remap_ops->free_irq)
+		remap_ops->free_irq(irq);
+}
+
+void compose_remapped_msi_msg(struct pci_dev *pdev,
+			      unsigned int irq, unsigned int dest,
+			      struct msi_msg *msg, u8 hpet_id)
+{
+	struct irq_cfg *cfg = irq_cfg(irq);
+
+	if (!irq_remapped(cfg))
+		native_compose_msi_msg(pdev, irq, dest, msg, hpet_id);
+	else if (remap_ops->compose_msi_msg)
+		remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
+}
+
+static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
+{
+	if (!remap_ops->msi_alloc_irq)
+		return -ENODEV;
+
+	return remap_ops->msi_alloc_irq(pdev, irq, nvec);
+}
+
+static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
+				  int index, int sub_handle)
+{
+	if (!remap_ops->msi_setup_irq)
+		return -ENODEV;
+
+	return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle);
+}
+
+int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
+{
+	int ret;
+
+	if (!remap_ops->alloc_hpet_msi)
+		return -ENODEV;
+
+	ret = remap_ops->alloc_hpet_msi(irq, id);
+	if (ret)
+		return -EINVAL;
+
+	return default_setup_hpet_msi(irq, id);
+}
+
+void panic_if_irq_remap(const char *msg)
+{
+	if (irq_remapping_enabled)
+		panic(msg);
+}
+
+static void ir_ack_apic_edge(struct irq_data *data)
+{
+	ack_APIC_irq();
+}
+
+static void ir_ack_apic_level(struct irq_data *data)
+{
+	ack_APIC_irq();
+	eoi_ioapic_irq(data->irq, irqd_cfg(data));
+}
+
+static void ir_print_prefix(struct irq_data *data, struct seq_file *p)
+{
+	seq_printf(p, " IR-%s", data->chip->name);
+}
+
+void irq_remap_modify_chip_defaults(struct irq_chip *chip)
+{
+	chip->irq_print_chip = ir_print_prefix;
+	chip->irq_ack = ir_ack_apic_edge;
+	chip->irq_eoi = ir_ack_apic_level;
+	chip->irq_set_affinity = x86_io_apic_ops.set_affinity;
+}
+
+bool setup_remapped_irq(int irq, struct irq_cfg *cfg, struct irq_chip *chip)
+{
+	if (!irq_remapped(cfg))
+		return false;
+	irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
+	irq_remap_modify_chip_defaults(chip);
+	return true;
+}