Subject: [PATCH V1 11/11] arm64, pci, acpi: Support for ACPI based PCI hostbridge init

From: [email-masked] (Sinan Kaya)
Date: Tue, 3 Nov 2015 10:10:21 -0500

On 11/3/2015 9:39 AM, Tomasz Nowicki wrote:
>>>> +struct pci_ops pci_root_ops = {
>>>> +    .map_bus = pci_mcfg_dev_base,
>>>> +    .read = pci_generic_config_read,
>>>> +    .write = pci_generic_config_write,
>>>
>>>
>>> Can you change these with pci_generic_config_read32 and
>>> pci_generic_config_write32? We have some targets that can only do 32
>>> bits PCI config space access.
>>
>> No.
>>
>> http://www.spinics.net/lists/linux-pci/msg44869.html
>>
>> Can you be a bit more specific please ?
>>
>> Sigh. Looks like we have to start adding platform specific quirks even
>> before we merged the generic ACPI PCIe host controller implementation.
>>
>
> The sad reality... But my next version will be still generic. Once that
> one appear to be in good shape then we can add quirks.

Thanks.

I don't see anywhere in the SBSA spec addendum that the PCI 
configuration space section that unaligned accesses *MUST* be supported.

If this is required, please have this info added to the spec. I can work 
with the designers for the next chip.

Unaligned access on the current hardware returns incomplete values or 
can cause bus faults. The behavior is undefined.

-- 
Sinan Kaya
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a 
Linux Foundation Collaborative Project