[PATCH V2 3/5] PCI: xilinx: Modifying AXI PCIe Host Bridge driver to work on both Zynq and Microblaze

[arnd@arndb.de (Arnd Bergmann)]

On Thursday 28 January 2016 13:20:56 Bharat Kumar Gogada wrote:
> > Subject: Re: [PATCH V2 3/5] PCI: xilinx: Modifying AXI PCIe Host Bridge driver
> > to work on both Zynq and Microblaze
> > 
> > On Wednesday 27 January 2016 14:33:45 Bharat Kumar Gogada wrote:
> > > > > @@ -705,7 +715,9 @@ static int xilinx_pcie_probe(struct
> > > > > platform_device *pdev)  #endif
> > > > >     pci_scan_child_bus(bus);
> > > > >     pci_assign_unassigned_bus_resources(bus);
> > > > > +#ifdef CONFIG_ARM
> > > > >     pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
> > > > > +#endif
> > > > >     pci_bus_add_devices(bus);
> > > > >     platform_set_drvdata(pdev, port);
> > > >
> > > > Here it looks like microblaze gets it right. I'm not sure why we
> > > > still need the
> > > > pci_fixup_irqs() on ARM, but my feeling is that this should be fixed
> > > > in common code.
> > > In arm pci_fixup_irqs is called by pci_common_init_dev
> > (arch/arm/kernel/bios32.c), since this API is removed now, I was calling it
> > separately.
> > 
> > But who calls it in microblaze? If it works without the extra call there, can we
> > make it work the same way for ARM?
> > 
> In microblaze I have added pcibios_add_device call (similar to call in
> arch/arm64/kernel/pci.c ) in pci-common.c, which is being invoked by
> kernel core itself.

I see. In the upstream code you seem to do it in pcibios_setup_bus_devices(),
while arm64 and powerpc do it in pcibios_add_device().

> May be we can add similar on arm and test out, but
> we might need some cleanup in arch/arm/kernel/bios32.c

I think that would still just be a half-baked solution. This should
really be fully automatic. We could do it in the __weak
pcibios_add_device() for all architectures that don't override
it when the bus was probed from DT, or we could do it in
pci_read_irq().

	Arnd