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    SubjectRe: [PATCH 1/3] Loongson-2F: Flush the branch target history such as BTB and RAS
    Hello.

    Wu Zhangjin wrote:

    > From: Wu Zhangjin <wuzhangjin@gmail.com>
    >
    > As the Chapter 15: "Errata: Issue of Out-of-order in loongson"[1] shows, to
    > workaround the Issue of Loongson-2F,We need to do:
    >
    > "When switching from user model to kernel model, you should flush the branch
    > target history such as BTB and RAS."
    >
    > This patch did clear BTB(branch target buffer), forbid RAS(row address strobe)
    > via Loongson-2F's 64bit diagnostic register.
    >
    > [1] Chinese Version: http://www.loongson.cn/uploadfile/file/200808211
    > [2] English Version of Chapter 15:
    > http://groups.google.com.hk/group/loongson-dev/msg/e0d2e220958f10a6?dmode=source
    >
    > Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
    > ---
    > arch/mips/include/asm/stackframe.h | 19 +++++++++++++++++++
    > 1 files changed, 19 insertions(+), 0 deletions(-)
    >
    > diff --git a/arch/mips/include/asm/stackframe.h b/arch/mips/include/asm/stackframe.h
    > index 3b6da33..b84cfda 100644
    > --- a/arch/mips/include/asm/stackframe.h
    > +++ b/arch/mips/include/asm/stackframe.h
    > @@ -121,6 +121,25 @@
    > .endm
    > #else
    > .macro get_saved_sp /* Uniprocessor variation */
    > +#ifdef CONFIG_CPU_LOONGSON2F
    > + /*
    > + * Clear BTB(branch target buffer), forbid RAS(row address
    > + * strobe)

    No spaces before the left paren...

    > to workaround the Out-of-oder Issue in Loongson2F
    > + * via it's diagnostic register.
    >

    Only "its".

    > + */
    > + move k0, ra
    >

    Operands misalined...

    WBR, Sergei

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