Re: [Patch v7 4/7] PCI/ACPI: Add interface acpi_pci_root_create()

[Tomasz Nowicki]

On 20.11.2015 11:18, Lorenzo Pieralisi wrote:
> Hi Jiang,
>
> On Sat, Nov 14, 2015 at 01:49:08AM +0800, Jiang Liu wrote:
>
> [...]
>
> > > Not really. My concern is that there might be platforms out there with
> > > an offset between the CPU and PCI physical address spaces, and if we
> > > remove the offset value in acpi_decode_space we can break them,
> > > because in the kernel struct resource data we have to have CPU physical
> > > addresses, not PCI ones. If offset == 0, we are home and dry, I do not
> > > understand why that's a given, which is what we would assume if Jiang's
> > > patch is merged as-is unless I am mistaken.
> > We try to exclude offset from struct resource in generic ACPI code,
> > and it's the arch's responsibility to decide how to manipulate struct
> > resource object if offset is not zero.
> >
> > Currently offset is always zero for x86, and IA64 has arch specific
> > code to handle non-zero offset. So we should be safe without breaking
> > existing code. For ARM64, it's a little different from IA64 so it's
> > hard to share code between IA64 and ARM64.
>
> Can you drop the patch on the mailing lists please, we actually need it
> to get ACPI ARM64 PCIe support in the kernel, please let me know how
> you want to handle this and if you need any help.

Kindly reminder.

Regards,
Tomasz
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/