[PATCH] powerpc: Workaround oldworld OF bug with IRQs & P2P bridges
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2006-12-14 20:13:31
On some oldworld PowerMacs, OF doesn't assign interrupts properly beyond P2P bridges. Fortunately, the fix is easy as all those machines just wire all IRQ lines together to one IRQ which is assigned to the bridge itself. We already have a special function for parsing Apple OldWorld interrupts which are special, so let's add to it the ability to walk up the PCI tree to find interrupts. This fixes irqs on the lower slots of s900 clones among others. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- I'll also send that to -stable once it's been in for a few weeks. Index: linux-work/arch/powerpc/kernel/prom_parse.c ===================================================================
--- linux-work.orig/arch/powerpc/kernel/prom_parse.c 2006-12-14 09:27:22.000000000 +1100
+++ linux-work/arch/powerpc/kernel/prom_parse.c 2006-12-14 09:29:36.000000000 +1100@@ -920,9 +920,20 @@ /* * Old machines just have a list of interrupt numbers - * and no interrupt-controller nodes. + * and no interrupt-controller nodes. We also have dodgy + * cases where the APPL,interrupts property is completely + * missing behind pci-pci bridges and we have to get it + * from the parent (the bridge itself, as apple just wired + * everything together on these) */ - ints = get_property(device, "AAPL,interrupts", &intlen); + while (device) { + ints = get_property(device, "AAPL,interrupts", &intlen); + if (ints != NULL) + break; + device = device->parent; + if (device && strcmp(device->type, "pci") != 0) + break; + } if (ints == NULL) return -EINVAL; intlen /= sizeof(u32);