acpi_pci_irq_enable (RE: 2.6.9-rc2-mm1)

Len Brown
2004-11-09T08:50:20Z

[-- Attachment #1: Type: text/plain, Size: 805 bytes --]

On Fri, 2004-09-17 at 02:50, Len Brown wrote:
> On Fri, 2004-09-17 at 01:18, Protasevich, Natalie wrote:
> > > On Thursday 16 September 2004 11:14 am, Jesse Barnes wrote:
> > > > On Thursday, September 16, 2004 2:40 am, Andrew Morton wrote:
> > > > bk-acpi.patch
> > > >
> > > > Looks like some changes in this patch break sn2. In particular,
> > this
> > > > hunk in acpi_pci_irq_enable():
> > > >
> > > > - return_VALUE(0);
> > > > + return_VALUE(-EINVAL);
> > > >

> I think the patch has pointed out that this routine really should be returning 0
> for success and non zero for failure; and returning dev->irq was
> probably a latent bug all along.

Jesse,
I think this one is correct, please let me know if you have any trouble
with it.

thanks,
-Len

[-- Attachment #2: irq0.patch --]
[-- Type: text/plain, Size: 5473 bytes --]

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
# 2004/11/09 03:08:42-05:00 len.brown@intel.com
# [ACPI] acpi_pci_irq_enable() now returns 0 on success.
# This bubbles all the way up to pci_enable_device().
# This allows IRQ0 to be used as a legal PCI device IRQ.
#
# The ES7000 uses an interrupt source override to assign pin20 to IRQ0.
# Then platform_rename_gsi assigns pin0 a high-numbered IRQ -- available
# for PCI devices. But IRQ0 needs to be a legal PCI IRQ in the lookup code
# to make it as far as the re-name code.
#
# Signed-off-by: Natalie Protasevich <Natalie.Protasevich@UNISYS.com>
# Signed-off-by: Len Brown <len.brown@intel.com>
#
# drivers/acpi/pci_link.c
# 2004/11/09 03:08:36-05:00 len.brown@intel.com +10 -5
# Import patch irq0_checks3.patch
#
# drivers/acpi/pci_irq.c
# 2004/11/09 03:08:36-05:00 len.brown@intel.com +28 -13
# Import patch irq0_checks3.patch
#
diff -Nru a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
--- a/drivers/acpi/pci_irq.c 2004-11-09 03:45:33 -05:00
+++ b/drivers/acpi/pci_irq.c 2004-11-09 03:45:33 -05:00
@@ -227,6 +227,11 @@
PCI Interrupt Routing Support
-------------------------------------------------------------------------- */

+/*
+ * acpi_pci_irq_lookup
+ * success: return IRQ >= 0
+ * failure: return -1
+ */
static int
acpi_pci_irq_lookup (
struct pci_bus *bus,
@@ -249,14 +254,14 @@
entry = acpi_pci_irq_find_prt_entry(segment, bus_nr, device, pin);
if (!entry) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PRT entry not found\n"));
- return_VALUE(0);
+ return_VALUE(-1);
}

if (entry->link.handle) {
irq = acpi_pci_link_get_irq(entry->link.handle, entry->link.index, edge_level, active_high_low);
- if (!irq) {
+ if (irq < 0) {
ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid IRQ link routing entry\n"));
- return_VALUE(0);
+ return_VALUE(-1);
}
} else {
irq = entry->link.index;
@@ -269,6 +274,11 @@
return_VALUE(irq);
}

+/*
+ * acpi_pci_irq_derive
+ * success: return IRQ >= 0
+ * failure: return < 0
+ */
static int
acpi_pci_irq_derive (
struct pci_dev *dev,
@@ -277,7 +287,7 @@
int *active_high_low)
{
struct pci_dev *bridge = dev;
- int irq = 0;
+ int irq = -1;
u8 bridge_pin = 0;

ACPI_FUNCTION_TRACE("acpi_pci_irq_derive");
@@ -289,7 +299,7 @@
* Attempt to derive an IRQ for this device from a parent bridge's
* PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
*/
- while (!irq && bridge->bus->self) {
+ while (irq < 0 && bridge->bus->self) {
pin = (pin + PCI_SLOT(bridge->devfn)) % 4;
bridge = bridge->bus->self;

@@ -299,7 +309,7 @@
if (!bridge_pin) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"No interrupt pin configured for device %s\n", pci_name(bridge)));
- return_VALUE(0);
+ return_VALUE(-1);
}
/* Pin is from 0 to 3 */
bridge_pin --;
@@ -310,9 +320,9 @@
pin, edge_level, active_high_low);
}

- if (!irq) {
+ if (irq < 0) {
ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Unable to derive IRQ for device %s\n", pci_name(dev)));
- return_VALUE(0);
+ return_VALUE(-1);
}

ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Derive IRQ %d for device %s from %s\n",
@@ -321,6 +331,11 @@
return_VALUE(irq);
}

+/*
+ * acpi_pci_irq_enable
+ * success: return 0
+ * failure: return < 0
+ */

int
acpi_pci_irq_enable (
@@ -358,20 +373,20 @@
* If no PRT entry was found, we'll try to derive an IRQ from the
* device's parent bridge.
*/
- if (!irq)
+ if (irq < 0)
irq = acpi_pci_irq_derive(dev, pin, &edge_level, &active_high_low);

/*
* No IRQ known to the ACPI subsystem - maybe the BIOS /
* driver reported one, then use it. Exit in any case.
*/
- if (!irq) {
+ if (irq < 0) {
printk(KERN_WARNING PREFIX "PCI interrupt %s[%c]: no GSI",
pci_name(dev), ('A' + pin));
/* Interrupt Line values above 0xF are forbidden */
- if (dev->irq && (dev->irq <= 0xF)) {
+ if (dev->irq >= 0 && (dev->irq <= 0xF)) {
printk(" - using IRQ %d\n", dev->irq);
- return_VALUE(dev->irq);
+ return_VALUE(0);
}
else {
printk("\n");
@@ -388,5 +403,5 @@
(active_high_low == ACPI_ACTIVE_LOW) ? "low" : "high",
dev->irq);

- return_VALUE(dev->irq);
+ return_VALUE(0);
}
diff -Nru a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c
--- a/drivers/acpi/pci_link.c 2004-11-09 03:45:33 -05:00
+++ b/drivers/acpi/pci_link.c 2004-11-09 03:45:33 -05:00
@@ -577,6 +577,11 @@
return_VALUE(0);
}

+/*
+ * acpi_pci_link_get_irq
+ * success: return IRQ >= 0
+ * failure: return -1
+ */

int
acpi_pci_link_get_irq (
@@ -594,27 +599,27 @@
result = acpi_bus_get_device(handle, &device);
if (result) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid link device\n"));
- return_VALUE(0);
+ return_VALUE(-1);
}

link = (struct acpi_pci_link *) acpi_driver_data(device);
if (!link) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid link context\n"));
- return_VALUE(0);
+ return_VALUE(-1);
}

/* TBD: Support multiple index (IRQ) entries per Link Device */
if (index) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid index %d\n", index));
- return_VALUE(0);
+ return_VALUE(-1);
}

if (acpi_pci_link_allocate(link))
- return_VALUE(0);
+ return_VALUE(-1);

if (!link->irq.active) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Link active IRQ is 0!\n"));
- return_VALUE(0);
+ return_VALUE(-1);
}

if (edge_level) *edge_level = link->irq.edge_level;