MIPS: Loongson-2F: Flush the branch target history in BTB and RAS
authorWu Zhangjin <wuzhangjin@gmail.com>
Sat, 13 Mar 2010 04:34:15 +0000 (12:34 +0800)
committerRalf Baechle <ralf@linux-mips.org>
Mon, 12 Apr 2010 16:26:15 +0000 (17:26 +0100)
commitf1df323924e2fde14cbcd51209a8cbfc33e0c232
treea0f5a3c09e4a9e8ec3eb11bcc4e9d729b0af9dce
parentd814c28ceca8f659c0012eaec8e21eee43710716
MIPS: Loongson-2F: Flush the branch target history in BTB and RAS

As per chapter 15 "Errata: Issue of Out-of-order in loongson"[1] to work
around the Loongson 2F erratum we need to do:

"When switching from user mode to kernel mode, you should flush the
branch target history such as BTB and RAS."

[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>
Cc: linux-mips@linux-mips.org
Cc: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Patchwork: http://patchwork.linux-mips.org/patch/1066/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/include/asm/stackframe.h