[Patch Part3 v4] x86, PCI, MSI: Use hierarchy irqdomain to manage MSI interrupts

From: Jiang Liu
Date: Tue Nov 25 2014 - 21:21:52 EST


Enhance MSI code to support hierarchy irqdomain, it helps to make
the architecture more clear.

Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
---
Hi Thomas,
Sorry, my branch hasn't been updated to the latest tip/x86/apic
branch. With this patch rebased, all following patches should apply
cleanly without conflicts.
Regards!
Gerry
---
arch/x86/Kconfig | 1 +
arch/x86/include/asm/hw_irq.h | 9 ++-
arch/x86/include/asm/irq_remapping.h | 6 +-
arch/x86/include/asm/msi.h | 7 ++
arch/x86/kernel/apic/msi.c | 141 ++++++++++++++++++----------------
arch/x86/kernel/apic/vector.c | 2 +
drivers/iommu/irq_remapping.c | 1 -
7 files changed, 94 insertions(+), 73 deletions(-)
create mode 100644 arch/x86/include/asm/msi.h

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 14385ebfd560..e05be74d713d 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -883,6 +883,7 @@ config X86_LOCAL_APIC
depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
select IRQ_DOMAIN_HIERARCHY
+ select PCI_MSI_IRQ_DOMAIN if PCI_MSI

config X86_IO_APIC
def_bool X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index bd7881c5a57a..270c432971f8 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -110,9 +110,10 @@ struct irq_2_irte {
};
#endif /* CONFIG_IRQ_REMAP */

+struct irq_domain;
+
#ifdef CONFIG_X86_LOCAL_APIC
struct irq_data;
-struct irq_domain;
struct pci_dev;
struct msi_desc;

@@ -214,6 +215,12 @@ static inline void lock_vector_lock(void) {}
static inline void unlock_vector_lock(void) {}
#endif /* CONFIG_X86_LOCAL_APIC */

+#ifdef CONFIG_PCI_MSI
+extern void arch_init_msi_domain(struct irq_domain *domain);
+#else
+static inline void arch_init_msi_domain(struct irq_domain *domain) { }
+#endif
+
/* Statistics */
extern atomic_t irq_err_count;
extern atomic_t irq_mis_count;
diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 3421f10456d8..3b11f5a3e092 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -68,11 +68,7 @@ irq_remapping_get_irq_domain(struct irq_alloc_info *info);
extern void irq_remapping_print_chip(struct irq_data *data, struct seq_file *p);

/* Create PCI MSI/MSIx irqdomain, use @parent as the parent irqdomain. */
-static inline struct irq_domain *
-arch_create_msi_irq_domain(struct irq_domain *parent)
-{
- return NULL;
-}
+extern struct irq_domain *arch_create_msi_irq_domain(struct irq_domain *parent);

/* Get parent irqdomain for interrupt remapping irqdomain */
static inline struct irq_domain *arch_get_ir_parent_domain(void)
diff --git a/arch/x86/include/asm/msi.h b/arch/x86/include/asm/msi.h
new file mode 100644
index 000000000000..93724cc62177
--- /dev/null
+++ b/arch/x86/include/asm/msi.h
@@ -0,0 +1,7 @@
+#ifndef _ASM_X86_MSI_H
+#define _ASM_X86_MSI_H
+#include <asm/hw_irq.h>
+
+typedef struct irq_alloc_info msi_alloc_info_t;
+
+#endif /* _ASM_X86_MSI_H */
diff --git a/arch/x86/kernel/apic/msi.c b/arch/x86/kernel/apic/msi.c
index 10d9ae8f2166..e82ab7973477 100644
--- a/arch/x86/kernel/apic/msi.c
+++ b/arch/x86/kernel/apic/msi.c
@@ -3,6 +3,8 @@
*
* Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
* Moved from arch/x86/kernel/apic/io_apic.c.
+ * Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
+ * Convert to hierarchy irqdomain
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
@@ -21,6 +23,8 @@
#include <asm/apic.h>
#include <asm/irq_remapping.h>

+static struct irq_domain *msi_default_domain;
+
void native_compose_msi_msg(struct pci_dev *pdev,
unsigned int irq, unsigned int dest,
struct msi_msg *msg, u8 hpet_id)
@@ -114,102 +118,107 @@ static int msi_compose_msg(struct pci_dev *pdev, unsigned int irq,
return 0;
}

-static int
-msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
-{
- struct irq_cfg *cfg = irqd_cfg(data);
- struct msi_msg msg;
- unsigned int dest;
- int ret;
-
- ret = apic_set_affinity(data, mask, &dest);
- if (ret)
- return ret;
-
- __get_cached_msi_msg(data->msi_desc, &msg);
-
- msg.data &= ~MSI_DATA_VECTOR_MASK;
- msg.data |= MSI_DATA_VECTOR(cfg->vector);
- msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
- msg.address_lo |= MSI_ADDR_DEST_ID(dest);
-
- __pci_write_msi_msg(data->msi_desc, &msg);
-
- return IRQ_SET_MASK_OK_NOCOPY;
-}
-
/*
* IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
* which implement the MSI or MSI-X Capability Structure.
*/
-static struct irq_chip msi_chip = {
+static struct irq_chip pci_msi_controller = {
.name = "PCI-MSI",
.irq_unmask = pci_msi_unmask_irq,
.irq_mask = pci_msi_mask_irq,
- .irq_ack = apic_ack_edge,
- .irq_set_affinity = msi_set_affinity,
- .irq_retrigger = apic_retrigger_irq,
+ .irq_ack = irq_chip_ack_parent,
+ .irq_set_affinity = msi_domain_set_affinity,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .irq_print_chip = irq_remapping_print_chip,
+ .irq_compose_msi_msg = irq_msi_compose_msg,
+ .irq_write_msi_msg = pci_msi_domain_write_msg,
.flags = IRQCHIP_SKIP_SET_WAKE,
};

-int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc,
- unsigned int irq_base, unsigned int irq_offset)
+int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
- struct irq_chip *chip = &msi_chip;
- struct msi_msg msg;
- unsigned int irq = irq_base + irq_offset;
- int ret;
+ struct irq_domain *domain;
+ struct irq_alloc_info info;

- ret = msi_compose_msg(dev, irq, &msg, -1);
- if (ret < 0)
- return ret;
+ init_irq_alloc_info(&info, NULL);
+ info.type = X86_IRQ_ALLOC_TYPE_MSI;
+ info.msi_dev = dev;

- irq_set_msi_desc_off(irq_base, irq_offset, msidesc);
+ domain = irq_remapping_get_irq_domain(&info);
+ if (domain == NULL)
+ domain = msi_default_domain;
+ if (domain == NULL)
+ return -ENOSYS;

- /*
- * MSI-X message is written per-IRQ, the offset is always 0.
- * MSI message denotes a contiguous group of IRQs, written for 0th IRQ.
- */
- if (!irq_offset)
- pci_write_msi_msg(irq, &msg);
+ return pci_msi_domain_alloc_irqs(domain, dev, nvec, type);
+}

- setup_remapped_irq(irq, irq_cfg(irq), chip);
+void native_teardown_msi_irq(unsigned int irq)
+{
+ irq_domain_free_irqs(irq, 1);
+}

- irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
+static irq_hw_number_t pci_msi_get_hwirq(struct msi_domain_info *info,
+ msi_alloc_info_t *arg)
+{
+ return arg->msi_hwirq;
+}

- dev_dbg(&dev->dev, "irq %d for MSI/MSI-X\n", irq);
+static int pci_msi_prepare(struct irq_domain *domain, struct device *dev,
+ int nvec, msi_alloc_info_t *arg)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct msi_desc *desc = first_pci_msi_entry(pdev);
+
+ init_irq_alloc_info(arg, NULL);
+ arg->msi_dev = pdev;
+ if (desc->msi_attrib.is_msix) {
+ arg->type = X86_IRQ_ALLOC_TYPE_MSIX;
+ } else {
+ arg->type = X86_IRQ_ALLOC_TYPE_MSI;
+ arg->flags |= X86_IRQ_ALLOC_CONTIGOUS_VECTORS;
+ }

return 0;
}

-int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+static void pci_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
{
- struct msi_desc *msidesc;
- int irq, ret;
+ arg->msi_hwirq = pci_msi_domain_calc_hwirq(arg->msi_dev, desc);
+}

- /* Multiple MSI vectors only supported with interrupt remapping */
- if (type == PCI_CAP_ID_MSI && nvec > 1)
- return 1;
+static struct msi_domain_ops pci_msi_domain_ops = {
+ .get_hwirq = pci_msi_get_hwirq,
+ .msi_prepare = pci_msi_prepare,
+ .set_desc = pci_msi_set_desc,
+};

- list_for_each_entry(msidesc, &dev->msi_list, list) {
- irq = irq_domain_alloc_irqs(NULL, 1, NUMA_NO_NODE, NULL);
- if (irq <= 0)
- return -ENOSPC;
+static struct msi_domain_info pci_msi_domain_info = {
+ .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX,
+ .ops = &pci_msi_domain_ops,
+ .chip = &pci_msi_controller,
+ .handler = handle_edge_irq,
+ .handler_name = "edge",
+};

- ret = setup_msi_irq(dev, msidesc, irq, 0);
- if (ret < 0) {
- irq_domain_free_irqs(irq, 1);
- return ret;
- }
+void arch_init_msi_domain(struct irq_domain *parent)
+{
+ if (disable_apic)
+ return;

- }
- return 0;
+ msi_default_domain = pci_msi_create_irq_domain(NULL,
+ &pci_msi_domain_info, parent);
+ if (!msi_default_domain)
+ pr_warn("failed to initialize irqdomain for MSI/MSI-x.\n");
}

-void native_teardown_msi_irq(unsigned int irq)
+#ifdef CONFIG_IRQ_REMAP
+struct irq_domain *arch_create_msi_irq_domain(struct irq_domain *parent)
{
- irq_domain_free_irqs(irq, 1);
+ return msi_create_irq_domain(NULL, &pci_msi_domain_info, parent);
}
+#endif

#ifdef CONFIG_DMAR_TABLE
static int
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index f8340c72546f..e971c87f7858 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -364,6 +364,8 @@ int __init arch_early_irq_init(void)
BUG_ON(x86_vector_domain == NULL);
irq_set_default_host(x86_vector_domain);

+ arch_init_msi_domain(x86_vector_domain);
+
return arch_early_ioapic_init();
}

diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index 04ea5212cc28..6ec0099a16d1 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -171,7 +171,6 @@ static void __init irq_remapping_modify_x86_ops(void)
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;
}
--
1.7.10.4

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