linux-sg2042/drivers/iommu/intel_irq_remapping.c

1126 lines
26 KiB
C

#include <linux/interrupt.h>
#include <linux/dmar.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/hpet.h>
#include <linux/pci.h>
#include <linux/irq.h>
#include <asm/io_apic.h>
#include <asm/smp.h>
#include <asm/cpu.h>
#include <linux/intel-iommu.h>
#include <acpi/acpi.h>
#include <asm/irq_remapping.h>
#include <asm/pci-direct.h>
#include <asm/msidef.h>
#include "irq_remapping.h"
struct ioapic_scope {
struct intel_iommu *iommu;
unsigned int id;
unsigned int bus; /* PCI bus number */
unsigned int devfn; /* PCI devfn number */
};
struct hpet_scope {
struct intel_iommu *iommu;
u8 id;
unsigned int bus;
unsigned int devfn;
};
#define IR_X2APIC_MODE(mode) (mode ? (1 << 11) : 0)
#define IRTE_DEST(dest) ((x2apic_mode) ? dest : dest << 8)
static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
static struct hpet_scope ir_hpet[MAX_HPET_TBS];
static int ir_ioapic_num, ir_hpet_num;
static DEFINE_RAW_SPINLOCK(irq_2_ir_lock);
static struct irq_2_iommu *irq_2_iommu(unsigned int irq)
{
struct irq_cfg *cfg = irq_get_chip_data(irq);
return cfg ? &cfg->irq_2_iommu : NULL;
}
int get_irte(int irq, struct irte *entry)
{
struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
unsigned long flags;
int index;
if (!entry || !irq_iommu)
return -1;
raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
index = irq_iommu->irte_index + irq_iommu->sub_handle;
*entry = *(irq_iommu->iommu->ir_table->base + index);
raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
return 0;
}
static int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
{
struct ir_table *table = iommu->ir_table;
struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
struct irq_cfg *cfg = irq_get_chip_data(irq);
u16 index, start_index;
unsigned int mask = 0;
unsigned long flags;
int i;
if (!count || !irq_iommu)
return -1;
/*
* start the IRTE search from index 0.
*/
index = start_index = 0;
if (count > 1) {
count = __roundup_pow_of_two(count);
mask = ilog2(count);
}
if (mask > ecap_max_handle_mask(iommu->ecap)) {
printk(KERN_ERR
"Requested mask %x exceeds the max invalidation handle"
" mask value %Lx\n", mask,
ecap_max_handle_mask(iommu->ecap));
return -1;
}
raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
do {
for (i = index; i < index + count; i++)
if (table->base[i].present)
break;
/* empty index found */
if (i == index + count)
break;
index = (index + count) % INTR_REMAP_TABLE_ENTRIES;
if (index == start_index) {
raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
printk(KERN_ERR "can't allocate an IRTE\n");
return -1;
}
} while (1);
for (i = index; i < index + count; i++)
table->base[i].present = 1;
cfg->remapped = 1;
irq_iommu->iommu = iommu;
irq_iommu->irte_index = index;
irq_iommu->sub_handle = 0;
irq_iommu->irte_mask = mask;
raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
return index;
}
static int qi_flush_iec(struct intel_iommu *iommu, int index, int mask)
{
struct qi_desc desc;
desc.low = QI_IEC_IIDEX(index) | QI_IEC_TYPE | QI_IEC_IM(mask)
| QI_IEC_SELECTIVE;
desc.high = 0;
return qi_submit_sync(&desc, iommu);
}
static int map_irq_to_irte_handle(int irq, u16 *sub_handle)
{
struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
unsigned long flags;
int index;
if (!irq_iommu)
return -1;
raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
*sub_handle = irq_iommu->sub_handle;
index = irq_iommu->irte_index;
raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
return index;
}
static int set_irte_irq(int irq, struct intel_iommu *iommu, u16 index, u16 subhandle)
{
struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
struct irq_cfg *cfg = irq_get_chip_data(irq);
unsigned long flags;
if (!irq_iommu)
return -1;
raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
cfg->remapped = 1;
irq_iommu->iommu = iommu;
irq_iommu->irte_index = index;
irq_iommu->sub_handle = subhandle;
irq_iommu->irte_mask = 0;
raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
return 0;
}
static int modify_irte(int irq, struct irte *irte_modified)
{
struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
struct intel_iommu *iommu;
unsigned long flags;
struct irte *irte;
int rc, index;
if (!irq_iommu)
return -1;
raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
iommu = irq_iommu->iommu;
index = irq_iommu->irte_index + irq_iommu->sub_handle;
irte = &iommu->ir_table->base[index];
set_64bit(&irte->low, irte_modified->low);
set_64bit(&irte->high, irte_modified->high);
__iommu_flush_cache(iommu, irte, sizeof(*irte));
rc = qi_flush_iec(iommu, index, 0);
raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
return rc;
}
static struct intel_iommu *map_hpet_to_ir(u8 hpet_id)
{
int i;
for (i = 0; i < MAX_HPET_TBS; i++)
if (ir_hpet[i].id == hpet_id)
return ir_hpet[i].iommu;
return NULL;
}
static struct intel_iommu *map_ioapic_to_ir(int apic)
{
int i;
for (i = 0; i < MAX_IO_APICS; i++)
if (ir_ioapic[i].id == apic)
return ir_ioapic[i].iommu;
return NULL;
}
static struct intel_iommu *map_dev_to_ir(struct pci_dev *dev)
{
struct dmar_drhd_unit *drhd;
drhd = dmar_find_matched_drhd_unit(dev);
if (!drhd)
return NULL;
return drhd->iommu;
}
static int clear_entries(struct irq_2_iommu *irq_iommu)
{
struct irte *start, *entry, *end;
struct intel_iommu *iommu;
int index;
if (irq_iommu->sub_handle)
return 0;
iommu = irq_iommu->iommu;
index = irq_iommu->irte_index + irq_iommu->sub_handle;
start = iommu->ir_table->base + index;
end = start + (1 << irq_iommu->irte_mask);
for (entry = start; entry < end; entry++) {
set_64bit(&entry->low, 0);
set_64bit(&entry->high, 0);
}
return qi_flush_iec(iommu, index, irq_iommu->irte_mask);
}
static int free_irte(int irq)
{
struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
unsigned long flags;
int rc;
if (!irq_iommu)
return -1;
raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
rc = clear_entries(irq_iommu);
irq_iommu->iommu = NULL;
irq_iommu->irte_index = 0;
irq_iommu->sub_handle = 0;
irq_iommu->irte_mask = 0;
raw_spin_unlock_irqrestore(&irq_2_ir_lock, flags);
return rc;
}
/*
* source validation type
*/
#define SVT_NO_VERIFY 0x0 /* no verification is required */
#define SVT_VERIFY_SID_SQ 0x1 /* verify using SID and SQ fields */
#define SVT_VERIFY_BUS 0x2 /* verify bus of request-id */
/*
* source-id qualifier
*/
#define SQ_ALL_16 0x0 /* verify all 16 bits of request-id */
#define SQ_13_IGNORE_1 0x1 /* verify most significant 13 bits, ignore
* the third least significant bit
*/
#define SQ_13_IGNORE_2 0x2 /* verify most significant 13 bits, ignore
* the second and third least significant bits
*/
#define SQ_13_IGNORE_3 0x3 /* verify most significant 13 bits, ignore
* the least three significant bits
*/
/*
* set SVT, SQ and SID fields of irte to verify
* source ids of interrupt requests
*/
static void set_irte_sid(struct irte *irte, unsigned int svt,
unsigned int sq, unsigned int sid)
{
if (disable_sourceid_checking)
svt = SVT_NO_VERIFY;
irte->svt = svt;
irte->sq = sq;
irte->sid = sid;
}
static int set_ioapic_sid(struct irte *irte, int apic)
{
int i;
u16 sid = 0;
if (!irte)
return -1;
for (i = 0; i < MAX_IO_APICS; i++) {
if (ir_ioapic[i].id == apic) {
sid = (ir_ioapic[i].bus << 8) | ir_ioapic[i].devfn;
break;
}
}
if (sid == 0) {
pr_warning("Failed to set source-id of IOAPIC (%d)\n", apic);
return -1;
}
set_irte_sid(irte, 1, 0, sid);
return 0;
}
static int set_hpet_sid(struct irte *irte, u8 id)
{
int i;
u16 sid = 0;
if (!irte)
return -1;
for (i = 0; i < MAX_HPET_TBS; i++) {
if (ir_hpet[i].id == id) {
sid = (ir_hpet[i].bus << 8) | ir_hpet[i].devfn;
break;
}
}
if (sid == 0) {
pr_warning("Failed to set source-id of HPET block (%d)\n", id);
return -1;
}
/*
* Should really use SQ_ALL_16. Some platforms are broken.
* While we figure out the right quirks for these broken platforms, use
* SQ_13_IGNORE_3 for now.
*/
set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_13_IGNORE_3, sid);
return 0;
}
static int set_msi_sid(struct irte *irte, struct pci_dev *dev)
{
struct pci_dev *bridge;
if (!irte || !dev)
return -1;
/* PCIe device or Root Complex integrated PCI device */
if (pci_is_pcie(dev) || !dev->bus->parent) {
set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
(dev->bus->number << 8) | dev->devfn);
return 0;
}
bridge = pci_find_upstream_pcie_bridge(dev);
if (bridge) {
if (pci_is_pcie(bridge))/* this is a PCIe-to-PCI/PCIX bridge */
set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16,
(bridge->bus->number << 8) | dev->bus->number);
else /* this is a legacy PCI bridge */
set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
(bridge->bus->number << 8) | bridge->devfn);
}
return 0;
}
static void iommu_set_irq_remapping(struct intel_iommu *iommu, int mode)
{
u64 addr;
u32 sts;
unsigned long flags;
addr = virt_to_phys((void *)iommu->ir_table->base);
raw_spin_lock_irqsave(&iommu->register_lock, flags);
dmar_writeq(iommu->reg + DMAR_IRTA_REG,
(addr) | IR_X2APIC_MODE(mode) | INTR_REMAP_TABLE_REG_SIZE);
/* Set interrupt-remapping table pointer */
iommu->gcmd |= DMA_GCMD_SIRTP;
writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
readl, (sts & DMA_GSTS_IRTPS), sts);
raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
/*
* global invalidation of interrupt entry cache before enabling
* interrupt-remapping.
*/
qi_global_iec(iommu);
raw_spin_lock_irqsave(&iommu->register_lock, flags);
/* Enable interrupt-remapping */
iommu->gcmd |= DMA_GCMD_IRE;
iommu->gcmd &= ~DMA_GCMD_CFI; /* Block compatibility-format MSIs */
writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
readl, (sts & DMA_GSTS_IRES), sts);
/*
* With CFI clear in the Global Command register, we should be
* protected from dangerous (i.e. compatibility) interrupts
* regardless of x2apic status. Check just to be sure.
*/
if (sts & DMA_GSTS_CFIS)
WARN(1, KERN_WARNING
"Compatibility-format IRQs enabled despite intr remapping;\n"
"you are vulnerable to IRQ injection.\n");
raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
}
static int intel_setup_irq_remapping(struct intel_iommu *iommu, int mode)
{
struct ir_table *ir_table;
struct page *pages;
ir_table = iommu->ir_table = kzalloc(sizeof(struct ir_table),
GFP_ATOMIC);
if (!iommu->ir_table)
return -ENOMEM;
pages = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
INTR_REMAP_PAGE_ORDER);
if (!pages) {
printk(KERN_ERR "failed to allocate pages of order %d\n",
INTR_REMAP_PAGE_ORDER);
kfree(iommu->ir_table);
return -ENOMEM;
}
ir_table->base = page_address(pages);
iommu_set_irq_remapping(iommu, mode);
return 0;
}
/*
* Disable Interrupt Remapping.
*/
static void iommu_disable_irq_remapping(struct intel_iommu *iommu)
{
unsigned long flags;
u32 sts;
if (!ecap_ir_support(iommu->ecap))
return;
/*
* global invalidation of interrupt entry cache before disabling
* interrupt-remapping.
*/
qi_global_iec(iommu);
raw_spin_lock_irqsave(&iommu->register_lock, flags);
sts = dmar_readq(iommu->reg + DMAR_GSTS_REG);
if (!(sts & DMA_GSTS_IRES))
goto end;
iommu->gcmd &= ~DMA_GCMD_IRE;
writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
readl, !(sts & DMA_GSTS_IRES), sts);
end:
raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
}
static int __init dmar_x2apic_optout(void)
{
struct acpi_table_dmar *dmar;
dmar = (struct acpi_table_dmar *)dmar_tbl;
if (!dmar || no_x2apic_optout)
return 0;
return dmar->flags & DMAR_X2APIC_OPT_OUT;
}
static int __init intel_irq_remapping_supported(void)
{
struct dmar_drhd_unit *drhd;
if (disable_irq_remap)
return 0;
if (irq_remap_broken) {
printk(KERN_WARNING
"This system BIOS has enabled interrupt remapping\n"
"on a chipset that contains an erratum making that\n"
"feature unstable. To maintain system stability\n"
"interrupt remapping is being disabled. Please\n"
"contact your BIOS vendor for an update\n");
add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
disable_irq_remap = 1;
return 0;
}
if (!dmar_ir_support())
return 0;
for_each_drhd_unit(drhd) {
struct intel_iommu *iommu = drhd->iommu;
if (!ecap_ir_support(iommu->ecap))
return 0;
}
return 1;
}
static int __init intel_enable_irq_remapping(void)
{
struct dmar_drhd_unit *drhd;
bool x2apic_present;
int setup = 0;
int eim = 0;
x2apic_present = x2apic_supported();
if (parse_ioapics_under_ir() != 1) {
printk(KERN_INFO "Not enable interrupt remapping\n");
goto error;
}
if (x2apic_present) {
eim = !dmar_x2apic_optout();
if (!eim)
printk(KERN_WARNING
"Your BIOS is broken and requested that x2apic be disabled.\n"
"This will slightly decrease performance.\n"
"Use 'intremap=no_x2apic_optout' to override BIOS request.\n");
}
for_each_drhd_unit(drhd) {
struct intel_iommu *iommu = drhd->iommu;
/*
* If the queued invalidation is already initialized,
* shouldn't disable it.
*/
if (iommu->qi)
continue;
/*
* Clear previous faults.
*/
dmar_fault(-1, iommu);
/*
* Disable intr remapping and queued invalidation, if already
* enabled prior to OS handover.
*/
iommu_disable_irq_remapping(iommu);
dmar_disable_qi(iommu);
}
/*
* check for the Interrupt-remapping support
*/
for_each_drhd_unit(drhd) {
struct intel_iommu *iommu = drhd->iommu;
if (!ecap_ir_support(iommu->ecap))
continue;
if (eim && !ecap_eim_support(iommu->ecap)) {
printk(KERN_INFO "DRHD %Lx: EIM not supported by DRHD, "
" ecap %Lx\n", drhd->reg_base_addr, iommu->ecap);
goto error;
}
}
/*
* Enable queued invalidation for all the DRHD's.
*/
for_each_drhd_unit(drhd) {
int ret;
struct intel_iommu *iommu = drhd->iommu;
ret = dmar_enable_qi(iommu);
if (ret) {
printk(KERN_ERR "DRHD %Lx: failed to enable queued, "
" invalidation, ecap %Lx, ret %d\n",
drhd->reg_base_addr, iommu->ecap, ret);
goto error;
}
}
/*
* Setup Interrupt-remapping for all the DRHD's now.
*/
for_each_drhd_unit(drhd) {
struct intel_iommu *iommu = drhd->iommu;
if (!ecap_ir_support(iommu->ecap))
continue;
if (intel_setup_irq_remapping(iommu, eim))
goto error;
setup = 1;
}
if (!setup)
goto error;
irq_remapping_enabled = 1;
/*
* VT-d has a different layout for IO-APIC entries when
* interrupt remapping is enabled. So it needs a special routine
* to print IO-APIC entries for debugging purposes too.
*/
x86_io_apic_ops.print_entries = intel_ir_io_apic_print_entries;
pr_info("Enabled IRQ remapping in %s mode\n", eim ? "x2apic" : "xapic");
return eim ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
error:
/*
* handle error condition gracefully here!
*/
if (x2apic_present)
pr_warn("Failed to enable irq remapping. You are vulnerable to irq-injection attacks.\n");
return -1;
}
static void ir_parse_one_hpet_scope(struct acpi_dmar_device_scope *scope,
struct intel_iommu *iommu)
{
struct acpi_dmar_pci_path *path;
u8 bus;
int count;
bus = scope->bus;
path = (struct acpi_dmar_pci_path *)(scope + 1);
count = (scope->length - sizeof(struct acpi_dmar_device_scope))
/ sizeof(struct acpi_dmar_pci_path);
while (--count > 0) {
/*
* Access PCI directly due to the PCI
* subsystem isn't initialized yet.
*/
bus = read_pci_config_byte(bus, path->device, path->function,
PCI_SECONDARY_BUS);
path++;
}
ir_hpet[ir_hpet_num].bus = bus;
ir_hpet[ir_hpet_num].devfn = PCI_DEVFN(path->device, path->function);
ir_hpet[ir_hpet_num].iommu = iommu;
ir_hpet[ir_hpet_num].id = scope->enumeration_id;
ir_hpet_num++;
}
static void ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope,
struct intel_iommu *iommu)
{
struct acpi_dmar_pci_path *path;
u8 bus;
int count;
bus = scope->bus;
path = (struct acpi_dmar_pci_path *)(scope + 1);
count = (scope->length - sizeof(struct acpi_dmar_device_scope))
/ sizeof(struct acpi_dmar_pci_path);
while (--count > 0) {
/*
* Access PCI directly due to the PCI
* subsystem isn't initialized yet.
*/
bus = read_pci_config_byte(bus, path->device, path->function,
PCI_SECONDARY_BUS);
path++;
}
ir_ioapic[ir_ioapic_num].bus = bus;
ir_ioapic[ir_ioapic_num].devfn = PCI_DEVFN(path->device, path->function);
ir_ioapic[ir_ioapic_num].iommu = iommu;
ir_ioapic[ir_ioapic_num].id = scope->enumeration_id;
ir_ioapic_num++;
}
static int ir_parse_ioapic_hpet_scope(struct acpi_dmar_header *header,
struct intel_iommu *iommu)
{
struct acpi_dmar_hardware_unit *drhd;
struct acpi_dmar_device_scope *scope;
void *start, *end;
drhd = (struct acpi_dmar_hardware_unit *)header;
start = (void *)(drhd + 1);
end = ((void *)drhd) + header->length;
while (start < end) {
scope = start;
if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC) {
if (ir_ioapic_num == MAX_IO_APICS) {
printk(KERN_WARNING "Exceeded Max IO APICS\n");
return -1;
}
printk(KERN_INFO "IOAPIC id %d under DRHD base "
" 0x%Lx IOMMU %d\n", scope->enumeration_id,
drhd->address, iommu->seq_id);
ir_parse_one_ioapic_scope(scope, iommu);
} else if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_HPET) {
if (ir_hpet_num == MAX_HPET_TBS) {
printk(KERN_WARNING "Exceeded Max HPET blocks\n");
return -1;
}
printk(KERN_INFO "HPET id %d under DRHD base"
" 0x%Lx\n", scope->enumeration_id,
drhd->address);
ir_parse_one_hpet_scope(scope, iommu);
}
start += scope->length;
}
return 0;
}
/*
* Finds the assocaition between IOAPIC's and its Interrupt-remapping
* hardware unit.
*/
int __init parse_ioapics_under_ir(void)
{
struct dmar_drhd_unit *drhd;
int ir_supported = 0;
int ioapic_idx;
for_each_drhd_unit(drhd) {
struct intel_iommu *iommu = drhd->iommu;
if (ecap_ir_support(iommu->ecap)) {
if (ir_parse_ioapic_hpet_scope(drhd->hdr, iommu))
return -1;
ir_supported = 1;
}
}
if (!ir_supported)
return 0;
for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++) {
int ioapic_id = mpc_ioapic_id(ioapic_idx);
if (!map_ioapic_to_ir(ioapic_id)) {
pr_err(FW_BUG "ioapic %d has no mapping iommu, "
"interrupt remapping will be disabled\n",
ioapic_id);
return -1;
}
}
return 1;
}
int __init ir_dev_scope_init(void)
{
if (!irq_remapping_enabled)
return 0;
return dmar_dev_scope_init();
}
rootfs_initcall(ir_dev_scope_init);
static void disable_irq_remapping(void)
{
struct dmar_drhd_unit *drhd;
struct intel_iommu *iommu = NULL;
/*
* Disable Interrupt-remapping for all the DRHD's now.
*/
for_each_iommu(iommu, drhd) {
if (!ecap_ir_support(iommu->ecap))
continue;
iommu_disable_irq_remapping(iommu);
}
}
static int reenable_irq_remapping(int eim)
{
struct dmar_drhd_unit *drhd;
int setup = 0;
struct intel_iommu *iommu = NULL;
for_each_iommu(iommu, drhd)
if (iommu->qi)
dmar_reenable_qi(iommu);
/*
* Setup Interrupt-remapping for all the DRHD's now.
*/
for_each_iommu(iommu, drhd) {
if (!ecap_ir_support(iommu->ecap))
continue;
/* Set up interrupt remapping for iommu.*/
iommu_set_irq_remapping(iommu, eim);
setup = 1;
}
if (!setup)
goto error;
return 0;
error:
/*
* handle error condition gracefully here!
*/
return -1;
}
static void prepare_irte(struct irte *irte, int vector,
unsigned int dest)
{
memset(irte, 0, sizeof(*irte));
irte->present = 1;
irte->dst_mode = apic->irq_dest_mode;
/*
* Trigger mode in the IRTE will always be edge, and for IO-APIC, the
* actual level or edge trigger will be setup in the IO-APIC
* RTE. This will help simplify level triggered irq migration.
* For more details, see the comments (in io_apic.c) explainig IO-APIC
* irq migration in the presence of interrupt-remapping.
*/
irte->trigger_mode = 0;
irte->dlvry_mode = apic->irq_delivery_mode;
irte->vector = vector;
irte->dest_id = IRTE_DEST(dest);
irte->redir_hint = 1;
}
static int intel_setup_ioapic_entry(int irq,
struct IO_APIC_route_entry *route_entry,
unsigned int destination, int vector,
struct io_apic_irq_attr *attr)
{
int ioapic_id = mpc_ioapic_id(attr->ioapic);
struct intel_iommu *iommu = map_ioapic_to_ir(ioapic_id);
struct IR_IO_APIC_route_entry *entry;
struct irte irte;
int index;
if (!iommu) {
pr_warn("No mapping iommu for ioapic %d\n", ioapic_id);
return -ENODEV;
}
entry = (struct IR_IO_APIC_route_entry *)route_entry;
index = alloc_irte(iommu, irq, 1);
if (index < 0) {
pr_warn("Failed to allocate IRTE for ioapic %d\n", ioapic_id);
return -ENOMEM;
}
prepare_irte(&irte, vector, destination);
/* Set source-id of interrupt request */
set_ioapic_sid(&irte, ioapic_id);
modify_irte(irq, &irte);
apic_printk(APIC_VERBOSE, KERN_DEBUG "IOAPIC[%d]: "
"Set IRTE entry (P:%d FPD:%d Dst_Mode:%d "
"Redir_hint:%d Trig_Mode:%d Dlvry_Mode:%X "
"Avail:%X Vector:%02X Dest:%08X "
"SID:%04X SQ:%X SVT:%X)\n",
attr->ioapic, irte.present, irte.fpd, irte.dst_mode,
irte.redir_hint, irte.trigger_mode, irte.dlvry_mode,
irte.avail, irte.vector, irte.dest_id,
irte.sid, irte.sq, irte.svt);
memset(entry, 0, sizeof(*entry));
entry->index2 = (index >> 15) & 0x1;
entry->zero = 0;
entry->format = 1;
entry->index = (index & 0x7fff);
/*
* IO-APIC RTE will be configured with virtual vector.
* irq handler will do the explicit EOI to the io-apic.
*/
entry->vector = attr->ioapic_pin;
entry->mask = 0; /* enable IRQ */
entry->trigger = attr->trigger;
entry->polarity = attr->polarity;
/* Mask level triggered irqs.
* Use IRQ_DELAYED_DISABLE for edge triggered irqs.
*/
if (attr->trigger)
entry->mask = 1;
return 0;
}
/*
* Migrate the IO-APIC irq in the presence of intr-remapping.
*
* For both level and edge triggered, irq migration is a simple atomic
* update(of vector and cpu destination) of IRTE and flush the hardware cache.
*
* For level triggered, we eliminate the io-apic RTE modification (with the
* updated vector information), by using a virtual vector (io-apic pin number).
* Real vector that is used for interrupting cpu will be coming from
* the interrupt-remapping table entry.
*
* As the migration is a simple atomic update of IRTE, the same mechanism
* is used to migrate MSI irq's in the presence of interrupt-remapping.
*/
static int
intel_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
bool force)
{
struct irq_cfg *cfg = data->chip_data;
unsigned int dest, irq = data->irq;
struct irte irte;
int err;
if (!config_enabled(CONFIG_SMP))
return -EINVAL;
if (!cpumask_intersects(mask, cpu_online_mask))
return -EINVAL;
if (get_irte(irq, &irte))
return -EBUSY;
err = assign_irq_vector(irq, cfg, mask);
if (err)
return err;
err = apic->cpu_mask_to_apicid_and(cfg->domain, mask, &dest);
if (err) {
if (assign_irq_vector(irq, cfg, data->affinity))
pr_err("Failed to recover vector for irq %d\n", irq);
return err;
}
irte.vector = cfg->vector;
irte.dest_id = IRTE_DEST(dest);
/*
* Atomically updates the IRTE with the new destination, vector
* and flushes the interrupt entry cache.
*/
modify_irte(irq, &irte);
/*
* After this point, all the interrupts will start arriving
* at the new destination. So, time to cleanup the previous
* vector allocation.
*/
if (cfg->move_in_progress)
send_cleanup_vector(cfg);
cpumask_copy(data->affinity, mask);
return 0;
}
static void intel_compose_msi_msg(struct pci_dev *pdev,
unsigned int irq, unsigned int dest,
struct msi_msg *msg, u8 hpet_id)
{
struct irq_cfg *cfg;
struct irte irte;
u16 sub_handle = 0;
int ir_index;
cfg = irq_get_chip_data(irq);
ir_index = map_irq_to_irte_handle(irq, &sub_handle);
BUG_ON(ir_index == -1);
prepare_irte(&irte, cfg->vector, dest);
/* Set source-id of interrupt request */
if (pdev)
set_msi_sid(&irte, pdev);
else
set_hpet_sid(&irte, hpet_id);
modify_irte(irq, &irte);
msg->address_hi = MSI_ADDR_BASE_HI;
msg->data = sub_handle;
msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_IR_EXT_INT |
MSI_ADDR_IR_SHV |
MSI_ADDR_IR_INDEX1(ir_index) |
MSI_ADDR_IR_INDEX2(ir_index);
}
/*
* Map the PCI dev to the corresponding remapping hardware unit
* and allocate 'nvec' consecutive interrupt-remapping table entries
* in it.
*/
static int intel_msi_alloc_irq(struct pci_dev *dev, int irq, int nvec)
{
struct intel_iommu *iommu;
int index;
iommu = map_dev_to_ir(dev);
if (!iommu) {
printk(KERN_ERR
"Unable to map PCI %s to iommu\n", pci_name(dev));
return -ENOENT;
}
index = alloc_irte(iommu, irq, nvec);
if (index < 0) {
printk(KERN_ERR
"Unable to allocate %d IRTE for PCI %s\n", nvec,
pci_name(dev));
return -ENOSPC;
}
return index;
}
static int intel_msi_setup_irq(struct pci_dev *pdev, unsigned int irq,
int index, int sub_handle)
{
struct intel_iommu *iommu;
iommu = map_dev_to_ir(pdev);
if (!iommu)
return -ENOENT;
/*
* setup the mapping between the irq and the IRTE
* base index, the sub_handle pointing to the
* appropriate interrupt remap table entry.
*/
set_irte_irq(irq, iommu, index, sub_handle);
return 0;
}
static int intel_setup_hpet_msi(unsigned int irq, unsigned int id)
{
struct intel_iommu *iommu = map_hpet_to_ir(id);
int index;
if (!iommu)
return -1;
index = alloc_irte(iommu, irq, 1);
if (index < 0)
return -1;
return 0;
}
struct irq_remap_ops intel_irq_remap_ops = {
.supported = intel_irq_remapping_supported,
.prepare = dmar_table_init,
.enable = intel_enable_irq_remapping,
.disable = disable_irq_remapping,
.reenable = reenable_irq_remapping,
.enable_faulting = enable_drhd_fault_handling,
.setup_ioapic_entry = intel_setup_ioapic_entry,
.set_affinity = intel_ioapic_set_affinity,
.free_irq = free_irte,
.compose_msi_msg = intel_compose_msi_msg,
.msi_alloc_irq = intel_msi_alloc_irq,
.msi_setup_irq = intel_msi_setup_irq,
.setup_hpet_msi = intel_setup_hpet_msi,
};