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    SubjectRE: [PATCH 3/4] RISC-V: Support case insensitive ISA string parsing.
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    > -----Original Message-----
    > From: Paul Walmsley <paul.walmsley@sifive.com>
    > Sent: Saturday, July 27, 2019 5:00 AM
    > To: Atish Patra <Atish.Patra@wdc.com>
    > Cc: linux-kernel@vger.kernel.org; Alan Kao <alankao@andestech.com>;
    > Albert Ou <aou@eecs.berkeley.edu>; Allison Randal <allison@lohutok.net>;
    > Anup Patel <Anup.Patel@wdc.com>; Daniel Lezcano
    > <daniel.lezcano@linaro.org>; Greg Kroah-Hartman
    > <gregkh@linuxfoundation.org>; Johan Hovold <johan@kernel.org>; linux-
    > riscv@lists.infradead.org; Palmer Dabbelt <palmer@sifive.com>; Thomas
    > Gleixner <tglx@linutronix.de>
    > Subject: Re: [PATCH 3/4] RISC-V: Support case insensitive ISA string parsing.
    >
    > On Fri, 26 Jul 2019, Atish Patra wrote:
    >
    > > On 7/26/19 1:47 PM, Paul Walmsley wrote:
    > > > On Fri, 26 Jul 2019, Atish Patra wrote:
    > > >
    > > > > As per riscv specification, ISA naming strings are case
    > > > > insensitive. However, currently only lower case strings are parsed
    > > > > during cpu procfs.
    > > > >
    > > > > Support parsing of upper case letters as well.
    > > > >
    > > > > Signed-off-by: Atish Patra <atish.patra@wdc.com>
    > > >
    > > > Is there a use case that's driving this, or
    > >
    > > Currently, we use all lower case isa string in kvmtool. But somebody
    > > can have uppercase letters in future as spec allows it.
    > >
    > >
    > > can we just say, "use
    > > > lowercase letters" and leave it at that?
    > > >
    > >
    > > In that case, it will not comply with RISC-V spec. Is that okay ?
    >
    > I think that section of the specification is mostly concerned with someone
    > trying to define "f" as a different extension than "F", or something like that.
    > I'm not sure that it imposes any constraint that software must accept both
    > upper and lower case ISA strings.
    >
    > What gives me pause here is that this winds up impacting DT schema
    > validation:
    >
    > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Docu
    > mentation/devicetree/bindings/riscv/cpus.yaml#n41

    If 'f' and 'F' mean same extension as-per RISC-V spec then software should also
    interpret it that way hence this patch.

    Regards,
    Anup

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