| Message ID | 1484202504-96686-4-git-send-email-liudongdong3@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
[+cc Tomasz, Lorenzo] On Thu, Jan 12, 2017 at 02:28:24PM +0800, Dongdong Liu wrote: > arch/arm64/pci.c pcibios_alloc_irq() has the same function as > pci_fixup_irqs(), so we add condition #ifndef CONFIG_ARM64 for > pci_fixup_irqs(). > > Signed-off-by: Dongdong Liu <liudongdong3@huawei.com> > Reviewed-by: Gabriele Paoloni <gabriele.paoloni@huawei.com> > Reviewed-by: Zhou Wang <wangzhou1@hisilicon.com> > --- > drivers/pci/host/pci-host-common.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/pci/host/pci-host-common.c b/drivers/pci/host/pci-host-common.c > index e3c48b5..f160afc 100644 > --- a/drivers/pci/host/pci-host-common.c > +++ b/drivers/pci/host/pci-host-common.c > @@ -145,7 +145,9 @@ int pci_host_common_probe(struct platform_device *pdev, > return -ENODEV; > } > > +#ifndef CONFIG_ARM64 > pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci); > +#endif d8ed75d59332 ("ARM64: PCI: ACPI support for legacy IRQs parsing and consolidation with DT code") added pcibios_alloc_irq() for arm64. arm64 is the only arch that implements pcibios_alloc_irq(). And now you want to add an ifdef here so arm64 is the only arch that doesn't call pci_fixup_irqs(). I don't remember the details of why arm64 is so special here. Obviously we'd prefer not to have the ifdef and not to have the arm64-specific pcibios_alloc_irq(). > /* > * We insert PCI resources into the iomem_resource and > -- > 1.9.1 >
On Fri, Feb 03, 2017 at 02:45:30PM -0600, Bjorn Helgaas wrote: > [+cc Tomasz, Lorenzo] > > On Thu, Jan 12, 2017 at 02:28:24PM +0800, Dongdong Liu wrote: > > arch/arm64/pci.c pcibios_alloc_irq() has the same function as > > pci_fixup_irqs(), so we add condition #ifndef CONFIG_ARM64 for > > pci_fixup_irqs(). > > > > Signed-off-by: Dongdong Liu <liudongdong3@huawei.com> > > Reviewed-by: Gabriele Paoloni <gabriele.paoloni@huawei.com> > > Reviewed-by: Zhou Wang <wangzhou1@hisilicon.com> > > --- > > drivers/pci/host/pci-host-common.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/pci/host/pci-host-common.c b/drivers/pci/host/pci-host-common.c > > index e3c48b5..f160afc 100644 > > --- a/drivers/pci/host/pci-host-common.c > > +++ b/drivers/pci/host/pci-host-common.c > > @@ -145,7 +145,9 @@ int pci_host_common_probe(struct platform_device *pdev, > > return -ENODEV; > > } > > > > +#ifndef CONFIG_ARM64 > > pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci); > > +#endif > > d8ed75d59332 ("ARM64: PCI: ACPI support for legacy IRQs parsing and > consolidation with DT code") added pcibios_alloc_irq() for arm64. > > arm64 is the only arch that implements pcibios_alloc_irq(). And now > you want to add an ifdef here so arm64 is the only arch that doesn't > call pci_fixup_irqs(). > > I don't remember the details of why arm64 is so special here. > Obviously we'd prefer not to have the ifdef and not to have the > arm64-specific pcibios_alloc_irq(). Well, I am not sure ARM64 is more special than other architectures in this respect, actually I think that what ARM64 does is what we will end up doing when Matthew Minter's patches are merged and that's my aim for v4.12, pci_fixup_irqs() should not be used any longer, at least on ARM/ARM64 and I know what to do to make it disappear. ARM64 relies on pcibios_alloc_irq() because of probe sequence. Before d8ed75d59332 ("ARM64: PCI: ACPI support for legacy IRQs parsing and consolidation with DT code") legacy IRQs were assigned at pcibios_add_device() time. This does not work at all on ACPI (ie scan handlers dependency), so to have a single callback DT/ACPI we moved the allocation at pcibios_alloc_irq() time and I suspect that's where (in pci_device_probe()) the host bridge hook to init legacy IRQs will be called when we manage to merge Matt's code. I will send you Matt's code rebased for v4.12, I take an action on that (except for x86 code that IIRC is unfathomable from this perspective and that's what blocked Matt's attempt). Now this patch. Yes, using pci_fixup_irqs() is wrong on ARM64 (because we may reallocate an IRQ for a device that is already bound to a driver - but that's a problem on ARM too - ie multiple host controllers), the call has to be there for legacy IRQs to "work" on ARM though so the ifdef. How are we fixing this ? We merge this patch and I will remove this stuff completely for v4.12 by using Matt's approach (ie moving the legacy IRQ allocation to a per-host bridge callback ?) Thanks, Lorenzo
diff --git a/drivers/pci/host/pci-host-common.c b/drivers/pci/host/pci-host-common.c index e3c48b5..f160afc 100644 --- a/drivers/pci/host/pci-host-common.c +++ b/drivers/pci/host/pci-host-common.c @@ -145,7 +145,9 @@ int pci_host_common_probe(struct platform_device *pdev, return -ENODEV; } +#ifndef CONFIG_ARM64 pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci); +#endif /* * We insert PCI resources into the iomem_resource and