From 8d9df29db273ab9a330828f4f4f6669d293a730a Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Tue, 23 Mar 2010 00:02:43 +0100 Subject: [PATCH] MIPS: Sibyte: Apply M3 workaround only on affected chip types and versions. Previously it was unconditionally used on all Sibyte family SOCs. The M3 bug has to be handled in the TLB exception handler which is extremly performance sensitive, so this modification is expected to deliver around 2-3% performance improvment. This is important as required changes to the M3 workaround will make it more costly. Signed-off-by: Ralf Baechle --- arch/mips/include/asm/mach-sibyte/war.h | 6 +++++- arch/mips/sibyte/sb1250/setup.c | 15 +++++++++++++++ 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/arch/mips/include/asm/mach-sibyte/war.h b/arch/mips/include/asm/mach-sibyte/war.h index 7950ef4f032c2..743385d7b5f22 100644 --- a/arch/mips/include/asm/mach-sibyte/war.h +++ b/arch/mips/include/asm/mach-sibyte/war.h @@ -16,7 +16,11 @@ #if defined(CONFIG_SB1_PASS_1_WORKAROUNDS) || \ defined(CONFIG_SB1_PASS_2_WORKAROUNDS) -#define BCM1250_M3_WAR 1 +#ifndef __ASSEMBLY__ +extern int sb1250_m3_workaround_needed(void); +#endif + +#define BCM1250_M3_WAR sb1250_m3_workaround_needed() #define SIBYTE_1956_WAR 1 #else diff --git a/arch/mips/sibyte/sb1250/setup.c b/arch/mips/sibyte/sb1250/setup.c index 0444da1e23c24..92da3155ce074 100644 --- a/arch/mips/sibyte/sb1250/setup.c +++ b/arch/mips/sibyte/sb1250/setup.c @@ -87,6 +87,21 @@ static int __init setup_bcm1250(void) return ret; } +int sb1250_m3_workaround_needed(void) +{ + switch (soc_type) { + case K_SYS_SOC_TYPE_BCM1250: + case K_SYS_SOC_TYPE_BCM1250_ALT: + case K_SYS_SOC_TYPE_BCM1250_ALT2: + case K_SYS_SOC_TYPE_BCM1125: + case K_SYS_SOC_TYPE_BCM1125H: + return soc_pass < K_SYS_REVISION_BCM1250_C0; + + default: + return 0; + } +} + static int __init setup_bcm112x(void) { int ret = 0;