Re: [PATCH] [7/9] pasemi: Configure DMA controller interrupts
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2007-02-04 23:53:57
On Thu, 2007-02-01 at 22:54 -0600, Olof Johansson wrote:
plain text document attachment (pasemi-dma-irqs) The DMA controller on PWRficient is somewhat special -- has a PCI header so it looks like it's on the root PCI (-Express) root bus, but it uses more than the default number of interrupts (and they are hardwired). We need to wire up all interrupts for the DMA controller. The generic IRQ code will only map the primary interrupt from the PCI header (128), so add 129->211 by hand.
Or you can have them in the device-tree ... the generic code only maps PCI IRQ index 0 but nothing prevents your fixup code to map the other ones. However, I do wonder what is the point of creating a mapping and nor storing the resulting virq anywhere ? When are those IRQs actually used ? That is the place where the mapping should happen... There is no guarantee that the resulting virq from irq_create_mapping() will be the same as the HW irq you passed in (it will in -most- cases with the current code, but it's a bug to rely on that behaviour). Thus you should store the result of irq_create_mapping() and use that. I see no advantage in "pre-mapping" things that way. Ben.
quoted hunk ↗ jump to hunk
Signed-off-by: Olof Johansson <redacted> Index: merge/arch/powerpc/platforms/pasemi/pci.c ===================================================================--- merge.orig/arch/powerpc/platforms/pasemi/pci.c +++ merge/arch/powerpc/platforms/pasemi/pci.c@@ -163,6 +163,19 @@ static void __init pas_fixup_phb_resourc } +void __devinit pas_pci_irq_fixup(struct pci_dev *dev) +{ + /* DMA is special, 84 interrupts (128 -> 211), all but 128 + * need to be mapped by hand here. + */ + if (dev->vendor == 0x1959 && dev->device == 0xa007) { + int i; + for (i = 129; i < 212; i++) + irq_create_mapping(NULL, i); + } +} + + void __init pas_pci_init(void) { struct device_node *np, *root;Index: merge/arch/powerpc/platforms/pasemi/setup.c ===================================================================--- merge.orig/arch/powerpc/platforms/pasemi/setup.c +++ merge/arch/powerpc/platforms/pasemi/setup.c@@ -242,4 +242,5 @@ define_machine(pas) { .check_legacy_ioport = pas_check_legacy_ioport, .progress = pas_progress, .machine_check_exception = pas_machine_check_handler, + .pci_irq_fixup = pas_pci_irq_fixup, };Index: merge/arch/powerpc/platforms/pasemi/pasemi.h ===================================================================--- merge.orig/arch/powerpc/platforms/pasemi/pasemi.h +++ merge/arch/powerpc/platforms/pasemi/pasemi.h@@ -3,6 +3,7 @@ extern unsigned long pas_get_boot_time(void); extern void pas_pci_init(void); +extern void __devinit pas_pci_irq_fixup(struct pci_dev *dev); extern void __init pasemi_idle_init(void); --_______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev