[PATCH 03/12] x86/PCI: use config space encoding for interrupt pins

Bjorn Helgaas
2008-12-09T23:11:56Z

Keep "pin" encoded as it is in the "Interrupt Pin" value in PCI config
space, i.e., 0=device doesn't use interrupts, 1=INTA, ..., 4=INTD.

This makes the bridge INTx swizzle match other architectures.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
---
arch/x86/pci/irq.c | 44 ++++++++++++++++++++------------------------
1 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/arch/x86/pci/irq.c b/arch/x86/pci/irq.c
index 15c3e69..5d1ce1c 100644
--- a/arch/x86/pci/irq.c
+++ b/arch/x86/pci/irq.c
@@ -888,7 +888,6 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
dev_dbg(&dev->dev, "no interrupt pin\n");
return 0;
}
- pin = pin - 1;

/* Find IRQ routing entry */

@@ -898,17 +897,17 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
info = pirq_get_info(dev);
if (!info) {
dev_dbg(&dev->dev, "PCI INT %c not found in routing table\n",
- 'A' + pin);
+ 'A' + pin - 1);
return 0;
}
- pirq = info->irq[pin].link;
- mask = info->irq[pin].bitmap;
+ 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);
+ dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + pin - 1);
return 0;
}
dev_dbg(&dev->dev, "PCI INT %c -> PIRQ %02x, mask %04x, excl %04x",
- 'A' + pin, pirq, mask, pirq_table->exclusive_irqs);
+ 'A' + pin - 1, pirq, mask, pirq_table->exclusive_irqs);
mask &= pcibios_irq_mask;

/* Work around broken HP Pavilion Notebooks which assign USB to
@@ -950,7 +949,7 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
newirq = i;
}
}
- dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + pin, newirq);
+ dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + pin - 1, newirq);

/* Check if it is hardcoded */
if ((pirq & 0xf0) == 0xf0) {
@@ -978,18 +977,18 @@ 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, irq);
+ dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n", msg, 'A' + pin - 1, irq);

/* Update IRQ for all devices with the same pirq value */
while ((dev2 = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev2)) != NULL) {
pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &pin);
if (!pin)
continue;
- pin--;
+
info = pirq_get_info(dev2);
if (!info)
continue;
- if (info->irq[pin].link == pirq) {
+ if (info->irq[pin - 1].link == pirq) {
/*
* We refuse to override the dev->irq
* information. Give a warning!
@@ -1056,9 +1055,8 @@ static void __init pcibios_fixup_irqs(void)
/*
* interrupt pins are numbered starting from 1
*/
- pin--;
irq = IO_APIC_get_PCI_irq_vector(dev->bus->number,
- PCI_SLOT(dev->devfn), pin);
+ PCI_SLOT(dev->devfn), pin - 1);
/*
* Busses behind bridges are typically not listed in the
* MP-table. In this case we have to look up the IRQ
@@ -1071,22 +1069,22 @@ static void __init pcibios_fixup_irqs(void)
struct pci_dev *bridge = dev->bus->self;
int bus;

- pin = (pin + PCI_SLOT(dev->devfn)) % 4;
+ pin = (((pin - 1) + PCI_SLOT(dev->devfn)) % 4) + 1;
bus = bridge->bus->number;
irq = IO_APIC_get_PCI_irq_vector(bus,
- PCI_SLOT(bridge->devfn), pin);
+ PCI_SLOT(bridge->devfn), pin - 1);
if (irq >= 0)
dev_warn(&dev->dev,
"using bridge %s INT %c to "
"get IRQ %d\n",
pci_name(bridge),
- 'A' + pin, irq);
+ 'A' + pin - 1, irq);
}
if (irq >= 0) {
dev_info(&dev->dev,
"PCI->APIC IRQ transform: INT %c "
"-> IRQ %d\n",
- 'A' + pin, irq);
+ 'A' + pin - 1, irq);
dev->irq = irq;
}
}
@@ -1221,12 +1219,10 @@ static int pirq_enable_irq(struct pci_dev *dev)
if (pin && !pcibios_lookup_irq(dev, 1) && !dev->irq) {
char *msg = "";

- pin--; /* interrupt pins are numbered starting from 1 */
-
if (io_apic_assign_pci_irqs) {
int irq;

- irq = IO_APIC_get_PCI_irq_vector(dev->bus->number, PCI_SLOT(dev->devfn), pin);
+ irq = IO_APIC_get_PCI_irq_vector(dev->bus->number, PCI_SLOT(dev->devfn), pin - 1);
/*
* Busses behind bridges are typically not listed in the MP-table.
* In this case we have to look up the IRQ based on the parent bus,
@@ -1237,20 +1233,20 @@ static int pirq_enable_irq(struct pci_dev *dev)
while (irq < 0 && dev->bus->parent) { /* go back to the bridge */
struct pci_dev *bridge = dev->bus->self;

- pin = (pin + PCI_SLOT(dev->devfn)) % 4;
+ pin = (((pin - 1) + PCI_SLOT(dev->devfn)) % 4) + 1;
irq = IO_APIC_get_PCI_irq_vector(bridge->bus->number,
- PCI_SLOT(bridge->devfn), pin);
+ PCI_SLOT(bridge->devfn), pin - 1);
if (irq >= 0)
dev_warn(&dev->dev, "using bridge %s "
"INT %c to get IRQ %d\n",
- pci_name(bridge), 'A' + pin,
+ pci_name(bridge), 'A' + pin - 1,
irq);
dev = bridge;
}
dev = temp_dev;
if (irq >= 0) {
dev_info(&dev->dev, "PCI->APIC IRQ transform: "
- "INT %c -> IRQ %d\n", 'A' + pin, irq);
+ "INT %c -> IRQ %d\n", 'A' + pin - 1, irq);
dev->irq = irq;
return 0;
} else
@@ -1269,7 +1265,7 @@ static int pirq_enable_irq(struct pci_dev *dev)
return 0;

dev_warn(&dev->dev, "can't find IRQ for PCI INT %c%s\n",
- 'A' + pin, msg);
+ 'A' + pin - 1, msg);
}
return 0;
}