Skip to content

L
linux
Commit d88a8b1c authored by Maciej W. Rozycki's avatar Maciej W. Rozycki Committed by Thomas Gleixner
Browse files
Options

x86/PCI: Handle IRQ swizzling with PIRQ routers 

Similarly to MP-tables PIRQ routing tables may not list devices behind 
PCI-to-PCI bridges, leading to interrupt routing failures, e.g.:

pci 0000:00:07.0: PIIX/ICH IRQ router [8086:7000]
pci 0000:02:00.0: ignoring bogus IRQ 255
pci 0000:02:01.0: ignoring bogus IRQ 255
pci 0000:02:02.0: ignoring bogus IRQ 255
pci 0000:04:00.0: ignoring bogus IRQ 255
pci 0000:04:00.3: ignoring bogus IRQ 255
pci 0000:00:11.0: PCI INT A -> PIRQ 63, mask deb8, excl 0c20
pci 0000:00:11.0: PCI INT A -> newirq 0
PCI: setting IRQ 11 as level-triggered
pci 0000:00:11.0: found PCI INT A -> IRQ 11
pci 0000:00:11.0: sharing IRQ 11 with 0000:00:07.2
pci 0000:02:00.0: PCI INT A not found in routing table
pci 0000:02:01.0: PCI INT A not found in routing table
pci 0000:02:02.0: PCI INT A not found in routing table
pci 0000:04:00.0: PCI INT A not found in routing table
pci 0000:04:00.3: PCI INT D not found in routing table
pci 0000:06:05.0: PCI INT A not found in routing table
pci 0000:06:08.0: PCI INT A not found in routing table
pci 0000:06:08.1: PCI INT B not found in routing table
pci 0000:06:08.2: PCI INT C not found in routing table

and consequently non-working devices.  Since PCI-to-PCI bridges have a 
standardised way of routing interrupts by the means of swizzling do it 
for configurations that use a PIRQ router as well, like with APIC-based 
setups, and use the determined corresponding topmost bridge's interrupt 
pin assignment to route a given device's interrupt:

pci 0000:00:07.0: PIIX/ICH IRQ router [8086:7000]
pci 0000:02:00.0: ignoring bogus IRQ 255
pci 0000:02:01.0: ignoring bogus IRQ 255
pci 0000:02:02.0: ignoring bogus IRQ 255
pci 0000:04:00.0: ignoring bogus IRQ 255
pci 0000:04:00.3: ignoring bogus IRQ 255
pci 0000:00:11.0: PCI INT A -> PIRQ 63, mask deb8, excl 0c20
pci 0000:00:11.0: PCI INT A -> newirq 0
PCI: setting IRQ 11 as level-triggered
pci 0000:00:11.0: found PCI INT A -> IRQ 11
pci 0000:00:11.0: sharing IRQ 11 with 0000:00:07.2
pci 0000:02:00.0: using bridge 0000:00:11.0 INT A to get INT A
pci 0000:00:11.0: sharing IRQ 11 with 0000:02:00.0
pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:04:00.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:04:00.3: using bridge 0000:00:11.0 INT A to get INT D
pci 0000:00:11.0: sharing IRQ 11 with 0000:04:00.3
pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A
pci 0000:06:08.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:06:08.1: using bridge 0000:00:11.0 INT D to get INT B
pci 0000:06:08.2: using bridge 0000:00:11.0 INT A to get INT C
pci 0000:00:11.0: sharing IRQ 11 with 0000:06:08.2
pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:02:01.0: PCI INT A -> PIRQ 60, mask deb8, excl 0c20
pci 0000:02:01.0: PCI INT A -> newirq 0
PCI: setting IRQ 10 as level-triggered
pci 0000:02:01.0: found PCI INT A -> IRQ 10
pci 0000:02:01.0: sharing IRQ 10 with 0000:00:14.0
pci 0000:02:00.0: using bridge 0000:00:11.0 INT A to get INT A
pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:04:00.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:02:01.0: sharing IRQ 10 with 0000:04:00.0
pci 0000:04:00.3: using bridge 0000:00:11.0 INT A to get INT D
pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A
pci 0000:06:08.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:06:08.1: using bridge 0000:00:11.0 INT D to get INT B
pci 0000:06:08.2: using bridge 0000:00:11.0 INT A to get INT C
pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:02:02.0: PCI INT A -> PIRQ 61, mask deb8, excl 0c20
pci 0000:02:02.0: PCI INT A -> newirq 0
PCI: setting IRQ 5 as level-triggered
pci 0000:02:02.0: found PCI INT A -> IRQ 5
pci 0000:02:02.0: sharing IRQ 5 with 0000:00:13.0
pci 0000:02:00.0: using bridge 0000:00:11.0 INT A to get INT A
pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:04:00.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:04:00.3: using bridge 0000:00:11.0 INT A to get INT D
pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A
pci 0000:06:08.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:02:02.0: sharing IRQ 5 with 0000:06:08.0
pci 0000:06:08.1: using bridge 0000:00:11.0 INT D to get INT B
pci 0000:06:08.2: using bridge 0000:00:11.0 INT A to get INT C
pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A
pci 0000:06:05.0: PCI INT A -> PIRQ 62, mask deb8, excl 0c20
pci 0000:06:05.0: PCI INT A -> newirq 0
pci 0000:06:05.0: found PCI INT A -> IRQ 5
pci 0000:06:05.0: sharing IRQ 5 with 0000:00:12.0
pci 0000:02:00.0: using bridge 0000:00:11.0 INT A to get INT A
pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:04:00.0: using bridge 0000:00:11.0 INT B to get INT A
pci 0000:04:00.3: using bridge 0000:00:11.0 INT A to get INT D
pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A
pci 0000:06:08.0: using bridge 0000:00:11.0 INT C to get INT A
pci 0000:06:08.1: using bridge 0000:00:11.0 INT D to get INT B
pci 0000:06:05.0: sharing IRQ 5 with 0000:06:08.1
pci 0000:06:08.2: using bridge 0000:00:11.0 INT A to get INT C

Adjust log messages accordingly.
Signed-off-by: default avatarMaciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203301538440.22465@angie.orcam.me.uk
parent 31324502
Hide whitespace changes
Inline Side-by-side
Showing with 47 additions and 13 deletions
arch/x86/pci/irq.c
View file @ d88a8b1c
......@@ -1138,7 +1138,7 @@ static void __init pirq_find_router(struct irq_router *r)
* for motherboard devices, so if a complete match is found, then give
* it precedence over a slot match.
*/
static struct irq_info *pirq_get_info(struct pci_dev *dev)
static struct irq_info *pirq_get_dev_info(struct pci_dev *dev)
{
struct irq_routing_table *rt = pirq_table;
int entries = (rt->size - sizeof(struct irq_routing_table)) /
......@@ -1157,11 +1157,42 @@ static struct irq_info *pirq_get_info(struct pci_dev *dev)
return slotinfo;
}
/*
* Buses behind bridges are typically not listed in the PIRQ routing table.
* Do the usual dance then and walk the tree of bridges up adjusting the
* pin number accordingly on the way until the originating root bus device
* has been reached and then use its routing information.
*/
static struct irq_info *pirq_get_info(struct pci_dev *dev, u8 *pin)
{
struct pci_dev *temp_dev = dev;
struct irq_info *info;
u8 temp_pin = *pin;
u8 dpin = temp_pin;
info = pirq_get_dev_info(dev);
while (!info && temp_dev->bus->parent) {
struct pci_dev *bridge = temp_dev->bus->self;
temp_pin = pci_swizzle_interrupt_pin(temp_dev, temp_pin);
info = pirq_get_dev_info(bridge);
if (info)
dev_warn(&dev->dev,
"using bridge %s INT %c to get INT %c\n",
pci_name(bridge),
'A' + temp_pin - 1, 'A' + dpin - 1);
temp_dev = bridge;
}
*pin = temp_pin;
return info;
}
static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
{
u8 pin;
struct irq_info *info;
int i, pirq, newirq;
u8 dpin, pin;
int irq = 0;
u32 mask;
struct irq_router *r = &pirq_router;
......@@ -1169,8 +1200,8 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
char *msg = NULL;
/* Find IRQ pin */
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
if (!pin) {
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &dpin);
if (!dpin) {
dev_dbg(&dev->dev, "no interrupt pin\n");
return 0;
}
......@@ -1183,20 +1214,21 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
if (!pirq_table)
return 0;
info = pirq_get_info(dev);
pin = dpin;
info = pirq_get_info(dev, &pin);
if (!info) {
dev_dbg(&dev->dev, "PCI INT %c not found in routing table\n",
'A' + pin - 1);
'A' + dpin - 1);
return 0;
}
pirq = info->irq[pin - 1].link;
mask = info->irq[pin - 1].bitmap;
if (!pirq) {
dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + pin - 1);
dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + dpin - 1);
return 0;
}
dev_dbg(&dev->dev, "PCI INT %c -> PIRQ %02x, mask %04x, excl %04x",
'A' + pin - 1, pirq, mask, pirq_table->exclusive_irqs);
'A' + dpin - 1, pirq, mask, pirq_table->exclusive_irqs);
mask &= pcibios_irq_mask;
/* Work around broken HP Pavilion Notebooks which assign USB to
......@@ -1238,7 +1270,7 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
newirq = i;
}
}
dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + pin - 1, newirq);
dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + dpin - 1, newirq);
/* Check if it is hardcoded */
if ((pirq & 0xf0) == 0xf0) {
......@@ -1272,15 +1304,17 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
return 0;
}
}
dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n", msg, 'A' + pin - 1, irq);
dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n",
msg, 'A' + dpin - 1, irq);
/* Update IRQ for all devices with the same pirq value */
for_each_pci_dev(dev2) {
pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &pin);
if (!pin)
pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &dpin);
if (!dpin)
continue;
info = pirq_get_info(dev2);
pin = dpin;
info = pirq_get_info(dev2, &pin);
if (!info)
continue;
if (info->irq[pin - 1].link == pirq) {
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7