diff options
| -rw-r--r-- | 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 3b6da3330e3..c8419129e77 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 (return address + * stack) to workaround the Out-of-order Issue in Loongson2F + * via its diagnostic register. + */ + move k0, ra + jal 1f + nop +1: jal 1f + nop +1: jal 1f + nop +1: jal 1f + nop +1: move ra, k0 + li k0, 3 + mtc0 k0, $22 +#endif /* CONFIG_CPU_LOONGSON2F */ #if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32) lui k1, %hi(kernelsp) #else |