Re: [PATCH] ACPI, PCI: Get PRT entry during acpi_pci_enable_irq()

From: Peter Hurley
Date: Tue Feb 12 2013 - 21:20:38 EST

On Tue, 2013-02-12 at 11:11 -0800, Yinghai Lu wrote:
> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
> [ 8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
> [ 8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
> bisect to
> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
> | PCI: Put pci_dev in device tree as early as possible
> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
> are scanned.
> Bjorn said:
> The bus number binding means acpi_pci_irq_add_prt() has to happen
> after enumerating everything below a bridge, and it will prevent us
> from doing any bus number reassignment for hotplug.
> I think we should remove the bus numbers from the cached _PRT (or
> maybe even remove the _PRT caching completely). When we enable a PCI
> device's IRQ, we should search up the PCI device tree looking for a
> _PRT associated with each node, and applying normal PCI bridge
> swizzling when we don't find a _PRT. I think this can be done without
> using PCI bus numbers at all.
> So here we try to remove _PRT caching completely.
> -v2: check !handle early.
> Reported-and-tested-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>

Actually true now :)

Reported-and-tested-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>

Regards and thanks again,
Peter Hurley

PS - I just happened to see this version on the list. Would you please
cc me on any future versions?

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