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author | David Daney <ddaney@caviumnetworks.com> | 2009-10-14 12:16:56 -0700 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2009-12-17 01:57:01 +0000 |
commit | 82622284dd2f8791f9759f3cef601520a8bc63b2 (patch) | |
tree | ee47f43af373d0c021cc83ff9e22925942e9d001 /arch/mips/include/asm/stackframe.h | |
parent | 92078e0618f525e22945040b5daea21d4b6d4a16 (diff) | |
download | blackbird-op-linux-82622284dd2f8791f9759f3cef601520a8bc63b2.tar.gz blackbird-op-linux-82622284dd2f8791f9759f3cef601520a8bc63b2.zip |
MIPS: Put PGD in C0_CONTEXT for 64-bit R2 processors.
Processors that support the mips64r2 ISA can in four instructions
convert a shifted PGD pointer stored in the upper bits of c0_context
into a usable pointer. By doing this we save a memory load and
associated potential cache miss in the TLB exception handlers.
Since the upper bits of c0_context were holding the CPU number, we
move this to the upper bits of c0_xcontext which doesn't have enough
bits to hold the PGD pointer, but has plenty for the CPU number.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/include/asm/stackframe.h')
-rw-r--r-- | arch/mips/include/asm/stackframe.h | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/arch/mips/include/asm/stackframe.h b/arch/mips/include/asm/stackframe.h index dd7e220e087b..3b6da3330e32 100644 --- a/arch/mips/include/asm/stackframe.h +++ b/arch/mips/include/asm/stackframe.h @@ -87,15 +87,19 @@ #ifdef CONFIG_SMP #ifdef CONFIG_MIPS_MT_SMTC #define PTEBASE_SHIFT 19 /* TCBIND */ +#define CPU_ID_REG CP0_TCBIND +#define CPU_ID_MFC0 mfc0 +#elif defined(CONFIG_MIPS_PGD_C0_CONTEXT) +#define PTEBASE_SHIFT 48 /* XCONTEXT */ +#define CPU_ID_REG CP0_XCONTEXT +#define CPU_ID_MFC0 MFC0 #else #define PTEBASE_SHIFT 23 /* CONTEXT */ +#define CPU_ID_REG CP0_CONTEXT +#define CPU_ID_MFC0 MFC0 #endif .macro get_saved_sp /* SMP variation */ -#ifdef CONFIG_MIPS_MT_SMTC - mfc0 k0, CP0_TCBIND -#else - MFC0 k0, CP0_CONTEXT -#endif + CPU_ID_MFC0 k0, CPU_ID_REG #if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32) lui k1, %hi(kernelsp) #else @@ -111,11 +115,7 @@ .endm .macro set_saved_sp stackp temp temp2 -#ifdef CONFIG_MIPS_MT_SMTC - mfc0 \temp, CP0_TCBIND -#else - MFC0 \temp, CP0_CONTEXT -#endif + CPU_ID_MFC0 \temp, CPU_ID_REG LONG_SRL \temp, PTEBASE_SHIFT LONG_S \stackp, kernelsp(\temp) .endm |