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Date:   Thu, 31 Aug 2023 18:04:39 +0800
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Subject: Re: [PATCH v2] pci: loongson: Workaround MIPS firmware MRRS settings
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To:     Huacai Chen <chenhuacai@kernel.org>, bhelgaas@google.com
Cc:     linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
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From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
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在 2023/8/31 17:42, Huacai Chen 写道:
> On Thu, Aug 31, 2023 at 4:58 PM Jiaxun Yang <jiaxun.yang@flygoat.com> wrote:
>>
>>
>> 在 2023/8/31 14:22, Huacai Chen 写道:
>>
>> [...]
>>> But it is worth to try, and you can walk the children to set mrrs when
>>> the quirk runs on bridges, I think.
>> No, this will break hotplug, I had managed to get hotplug work on 2K1000.
>> Also we have no guarantee on order of discovering devices.
>>>> but the old quirk should run on every single device.
>>> Your current patch has a drawback that both quirks will run for MIPS,
>>> and their order is random (though it may cause nothing, but not
>>> elegant).
>> Actually loongson_mrrs_quirk is declared by DECLARE_PCI_FIXUP_EARLY but
>> loongson_old_mrrs_quirk is declared by DECLARE_PCI_FIXUP_ENABLE,
>> which means loongson_old_mrrs_quirk always runs after loongson_mrrs_quirk as
>> expected.
> Then I think it is better to put this quirk in arch/mips/loongson64/,
> just as pci_fixup_radeon().

Hmm, spiting two quirks with similar functionality into two places 
doesn't sound
like a good idea.

PCI folks, what do you think?

Thanks.
- Jiaxun

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