From 54a24cbbd0184faffc37c39cd3a896f4ddac3e03 Mon Sep 17 00:00:00 2001
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Thu, 20 Dec 2007 15:10:02 +1100
Subject: [PATCH] [POWERPC] Fix PCI IRQ fallback code to not map IRQ 0
The PCI IRQ code has a fallback when the device-tree parsing fails, that
tries to map the interrupt indicated by PCI_INTERRUPT_LINE if the firmware
set something in there. This is a bit fragile but has proven useful in some
cases so far. However, it's causing us to incorrectly try to map interrupt 0
on various setups, so let's prevent that case, as none of the cases where
the fallback is legit should have an IRQ 0.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
---
arch/powerpc/kernel/pci-common.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index 88838b0f8b90b9..571854f2906c7d 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -225,10 +225,11 @@ int pci_read_irq_line(struct pci_dev *pci_dev)
if (pin == 0)
return -1;
if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_LINE, &line) ||
- line == 0xff) {
+ line == 0xff || line == 0) {
return -1;
}
- DBG(" -> no map ! Using irq line %d from PCI config\n", line);
+ DBG(" -> no map ! Using line %d (pin %d) from PCI config\n",
+ line, pin);
virq = irq_create_mapping(NULL, line);
if (virq != NO_IRQ)
--
GitLab