AMD IOMMU: add MSI interrupt support

The AMD IOMMU can generate interrupts for various reasons. This patch
adds the basic interrupt enabling infrastructure to the driver.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Joerg Roedel 2008-09-11 16:51:41 +02:00 committed by Ingo Molnar
parent 3eaf28a1cd
commit a80dc3e0e0
5 changed files with 120 additions and 1 deletions

View File

@ -553,6 +553,7 @@ config CALGARY_IOMMU_ENABLED_BY_DEFAULT
config AMD_IOMMU
bool "AMD IOMMU support"
select SWIOTLB
select PCI_MSI
depends on X86_64 && PCI && ACPI
help
With this option you can enable support for AMD IOMMU hardware in

View File

@ -49,6 +49,17 @@ static int iommu_has_npcache(struct amd_iommu *iommu)
return iommu->cap & IOMMU_CAP_NPCACHE;
}
/****************************************************************************
*
* Interrupt handling functions
*
****************************************************************************/
irqreturn_t amd_iommu_int_handler(int irq, void *data)
{
return IRQ_NONE;
}
/****************************************************************************
*
* IOMMU command queuing functions

View File

@ -22,6 +22,8 @@
#include <linux/gfp.h>
#include <linux/list.h>
#include <linux/sysdev.h>
#include <linux/interrupt.h>
#include <linux/msi.h>
#include <asm/pci-direct.h>
#include <asm/amd_iommu_types.h>
#include <asm/amd_iommu.h>
@ -515,17 +517,20 @@ static void __init set_device_exclusion_range(u16 devid, struct ivmd_header *m)
static void __init init_iommu_from_pci(struct amd_iommu *iommu)
{
int cap_ptr = iommu->cap_ptr;
u32 range;
u32 range, misc;
pci_read_config_dword(iommu->dev, cap_ptr + MMIO_CAP_HDR_OFFSET,
&iommu->cap);
pci_read_config_dword(iommu->dev, cap_ptr + MMIO_RANGE_OFFSET,
&range);
pci_read_config_dword(iommu->dev, cap_ptr + MMIO_MISC_OFFSET,
&misc);
iommu->first_device = calc_devid(MMIO_GET_BUS(range),
MMIO_GET_FD(range));
iommu->last_device = calc_devid(MMIO_GET_BUS(range),
MMIO_GET_LD(range));
iommu->evt_msi_num = MMIO_MSI_NUM(misc);
}
/*
@ -696,6 +701,8 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h)
if (!iommu->evt_buf)
return -ENOMEM;
iommu->int_enabled = false;
init_iommu_from_pci(iommu);
init_iommu_from_acpi(iommu, h);
init_iommu_devices(iommu);
@ -741,6 +748,95 @@ static int __init init_iommu_all(struct acpi_table_header *table)
return 0;
}
/****************************************************************************
*
* The following functions initialize the MSI interrupts for all IOMMUs
* in the system. Its a bit challenging because there could be multiple
* IOMMUs per PCI BDF but we can call pci_enable_msi(x) only once per
* pci_dev.
*
****************************************************************************/
static int __init iommu_setup_msix(struct amd_iommu *iommu)
{
struct amd_iommu *curr;
struct msix_entry entries[32]; /* only 32 supported by AMD IOMMU */
int nvec = 0, i;
list_for_each_entry(curr, &amd_iommu_list, list) {
if (curr->dev == iommu->dev) {
entries[nvec].entry = curr->evt_msi_num;
entries[nvec].vector = 0;
curr->int_enabled = true;
nvec++;
}
}
if (pci_enable_msix(iommu->dev, entries, nvec)) {
pci_disable_msix(iommu->dev);
return 1;
}
for (i = 0; i < nvec; ++i) {
int r = request_irq(entries->vector, amd_iommu_int_handler,
IRQF_SAMPLE_RANDOM,
"AMD IOMMU",
NULL);
if (r)
goto out_free;
}
return 0;
out_free:
for (i -= 1; i >= 0; --i)
free_irq(entries->vector, NULL);
pci_disable_msix(iommu->dev);
return 1;
}
static int __init iommu_setup_msi(struct amd_iommu *iommu)
{
int r;
struct amd_iommu *curr;
list_for_each_entry(curr, &amd_iommu_list, list) {
if (curr->dev == iommu->dev)
curr->int_enabled = true;
}
if (pci_enable_msi(iommu->dev))
return 1;
r = request_irq(iommu->dev->irq, amd_iommu_int_handler,
IRQF_SAMPLE_RANDOM,
"AMD IOMMU",
NULL);
if (r) {
pci_disable_msi(iommu->dev);
return 1;
}
return 0;
}
static int __init iommu_init_msi(struct amd_iommu *iommu)
{
if (iommu->int_enabled)
return 0;
if (pci_find_capability(iommu->dev, PCI_CAP_ID_MSIX))
return iommu_setup_msix(iommu);
else if (pci_find_capability(iommu->dev, PCI_CAP_ID_MSI))
return iommu_setup_msi(iommu);
return 1;
}
/****************************************************************************
*
* The next functions belong to the third pass of parsing the ACPI
@ -862,6 +958,7 @@ static void __init enable_iommus(void)
list_for_each_entry(iommu, &amd_iommu_list, list) {
iommu_set_exclusion_range(iommu);
iommu_init_msi(iommu);
iommu_enable(iommu);
}
}

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@ -20,10 +20,13 @@
#ifndef _ASM_X86_AMD_IOMMU_H
#define _ASM_X86_AMD_IOMMU_H
#include <linux/irqreturn.h>
#ifdef CONFIG_AMD_IOMMU
extern int amd_iommu_init(void);
extern int amd_iommu_init_dma_ops(void);
extern void amd_iommu_detect(void);
extern irqreturn_t amd_iommu_int_handler(int irq, void *data);
#else
static inline int amd_iommu_init(void) { return -ENODEV; }
static inline void amd_iommu_detect(void) { }

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@ -37,6 +37,7 @@
/* Capability offsets used by the driver */
#define MMIO_CAP_HDR_OFFSET 0x00
#define MMIO_RANGE_OFFSET 0x0c
#define MMIO_MISC_OFFSET 0x10
/* Masks, shifts and macros to parse the device range capability */
#define MMIO_RANGE_LD_MASK 0xff000000
@ -48,6 +49,7 @@
#define MMIO_GET_LD(x) (((x) & MMIO_RANGE_LD_MASK) >> MMIO_RANGE_LD_SHIFT)
#define MMIO_GET_FD(x) (((x) & MMIO_RANGE_FD_MASK) >> MMIO_RANGE_FD_SHIFT)
#define MMIO_GET_BUS(x) (((x) & MMIO_RANGE_BUS_MASK) >> MMIO_RANGE_BUS_SHIFT)
#define MMIO_MSI_NUM(x) ((x) & 0x1f)
/* Flag masks for the AMD IOMMU exclusion range */
#define MMIO_EXCL_ENABLE_MASK 0x01ULL
@ -255,10 +257,15 @@ struct amd_iommu {
u8 *evt_buf;
/* size of event buffer */
u32 evt_buf_size;
/* MSI number for event interrupt */
u16 evt_msi_num;
/* if one, we need to send a completion wait command */
int need_sync;
/* true if interrupts for this IOMMU are already enabled */
bool int_enabled;
/* default dma_ops domain for that IOMMU */
struct dma_ops_domain *default_dom;
};