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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>
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From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
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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.

Thanks
- Jiaxun

[...]