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Message-ID: <c01c0138-70a5-f2ce-e99e-fa1a76e04cb2@flygoat.com>
Date:   Wed, 19 Jul 2023 16:24:02 +0800
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Subject: Re: [PATCH] pci: loongson: Workaround MIPS firmware MRRS settings
To:     Huacai Chen <chenhuacai@kernel.org>
Cc:     linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
        bhelgaas@google.com, kw@linux.com, lpieralisi@kernel.org
References: <20230718133259.2867432-1-jiaxun.yang@flygoat.com>
 <CAAhV-H7bv1OmzT0E-SEF6w83gPYrTwnZfc0WpWMUmBB1T1MmqQ@mail.gmail.com>
From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
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在 2023/7/18 22:46, Huacai Chen 写道:
> Hi, Jiaxun,
>
> On Tue, Jul 18, 2023 at 9:33 PM Jiaxun Yang <jiaxun.yang@flygoat.com> wrote:
>> This is a partial revert of commit 8b3517f88ff2 ("PCI:
>> loongson: Prevent LS7A MRRS increases") for MIPS based Loongson.
>>
>> There are many MIPS based Loongson systems in wild that
>> shipped with firmware which does not set maximum MRRS properly.
>>
>> Limiting MRRS to 256 for all as MIPS Loongson comes with higher
>> MRRS support is considered rare.
>>
>> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217680
>> Fixes: 8b3517f88ff2 ("PCI: loongson: Prevent LS7A MRRS increases")
>> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
>> ---
>>   drivers/pci/controller/pci-loongson.c | 38 +++++++++++++++++++++++++++
>>   1 file changed, 38 insertions(+)
>>
>> diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c
>> index fe0f732f6e43..1cc3a5535dac 100644
>> --- a/drivers/pci/controller/pci-loongson.c
>> +++ b/drivers/pci/controller/pci-loongson.c
>> @@ -108,6 +108,44 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
>>   DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_LOONGSON,
>>                          DEV_LS7A_PCIE_PORT6, loongson_mrrs_quirk);
>>
>> +#ifdef CONFIG_MIPS
>> +static void loongson_firmware_mrrs_quirk(struct pci_dev *pdev)
>  From my point of view, loongson_old_mrrs_quirk() may be better.

Make sense to me, will rename in v2.

Thanks
- Jiaxun