Re: [PATCH V6 0/5] ECAM quirks handling for ARM64 platforms

From: Christopher Covington
Date: Fri Sep 23 2016 - 15:22:34 EST

On 09/23/2016 03:17 PM, Bjorn Helgaas wrote:
> On Fri, Sep 23, 2016 at 02:41:39PM -0400, Christopher Covington wrote:
>> On 09/22/2016 07:08 PM, Bjorn Helgaas wrote:
>>> On Wed, Sep 21, 2016 at 06:40:47PM -0400, Christopher Covington wrote:
>>>> Hi Bjorn,
>>>> On 09/21/2016 09:11 AM, Bjorn Helgaas wrote:
>>>>> On Tue, Sep 20, 2016 at 09:15:14PM -0400, cov@xxxxxxxxxxxxxx wrote:
>>>>>>> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c
>>>>>>> index eb14f74..bb3b8ad 100644
>>>>>>> --- a/drivers/acpi/pci_mcfg.c
>>>>>>> +++ b/drivers/acpi/pci_mcfg.c
>>>>>>> @@ -42,86 +42,59 @@ struct mcfg_fixup {
>>>>>>> struct resource cfgres;
>>>>>>> };
>>>>>>> -#define MCFG_DOM_ANY (-1)
>>>>>> Did you delete this because there were no current users, because you'd
>>>>>> prefer users just use "-1", or for some other reason?
>>>>> I removed it because there were no users of it and, more importantly,
>>>>> the code doesn't implement support for it.
>>>> It looks like a stale "First match against PCI topology <domain:bus>..."
>>>> comment remains.
>>> Yep. I removed the comment since it's sort of obvious from the code.
>>> I also renamed a few things and pulled the match out into a helper
>>> function.
>>> I also changed the dmesg note: I think the actual resource and the
>>> name of the pci_ecam_ops is more interesting than the table IDs (which
>>> I think are already elsewhere in the dmesg log).
>> It looks like the resource is already being printed from
>> drivers/pci/ecam.c:102.
> Yes, but I want a hint that a quirk has overridden it because that's a
> clue that there's something wonky about the platform or the firmware.
> But I guess it'd be nice to mirror the format of the existing info
> (mem first, then bus range).
>>> Here's the incremental diff, which I can't really test:
>> Here's what it looks like for me:
>> ACPI: PCI Root Bridge [PCI2] (domain 0002 [bus 00-1f])
>> acpi PNP0A08:02: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI]
>> acpi PNP0A08:02: _OSC: platform does not support [PCIeHotplug]
>> acpi PNP0A08:02: _OSC: OS now controls [PME AER PCIeCapability]
>> acpi PNP0A08:02: MCFG quirk: ECAM space for [bus 00-1f] at [mem 0xa0000000000-0xa0001ffffff] with pci_3
> Is "pci_3" really the entire name? If not, what happened to the rest?
> I was hoping for a symbol we could grep for.

The full name is pci_32b_ops. The print overflowed my tmux pane.

>> acpi PNP0A08:02: ECAM at [mem 0xa0000000000-0xa0001ffffff] for [bus 00-1f]
>> Remapped I/O 0x00000affffff0000 to [io 0x10000-0x1ffff window]
>> PCI host bridge to bus 0002:00


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