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From:   =?utf-8?Q?Krzysztof_Ha=C5=82asa?= <khalasa@piap.pl>
To:     Rob Herring <robh@kernel.org>
Cc:     Bjorn Helgaas <bhelgaas@google.com>,
        PCI <linux-pci@vger.kernel.org>,
        Artem Lapkin <email2tema@gmail.com>,
        Neil Armstrong <narmstrong@baylibre.com>,
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        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
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        <kw@linux.com>, Richard Zhu <hongxing.zhu@nxp.com>,
        Lucas Stach <l.stach@pengutronix.de>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] PCIe: limit Max Read Request Size on i.MX to 512 bytes
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Date:   Tue, 17 Aug 2021 06:29:26 +0200
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        (Rob Herring's message of "Mon, 16 Aug 2021 14:34:00 -0500")
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Rob Herring <robh@kernel.org> writes:

>> +#ifdef CONFIG_ARM
>> +       if (rq > max_pcie_mrrs)
>> +               rq =3D max_pcie_mrrs;
>> +#endif
>
> My objection wasn't having another kconfig option so much as I don't
> think we need one at all here unless Bjorn feels otherwise. It's 2
> bytes of data and about 3 instructions (load, cmp, store).
>
> If we do have a config option, using or basing on the arch is wrong.
> Has nothing to do with the arch. Are the other platforms needing this
> arm32 as well?

Yes,

I can buy the "universal ARM32 kernel" argument, but otherwise it's just
nonfunctional bloat. A small one, yes.
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Krzysztof "Chris" Ha=C5=82asa

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