From 202e059ce34d5c5e3ff8a542866c280d575ccb17 Mon Sep 17 00:00:00 2001 From: Wang Dongsheng Date: Tue, 17 Dec 2013 16:17:00 +0800 Subject: [PATCH] powerpc/85xx: add hardware automatically enter altivec idle state Each core's AltiVec unit may be placed into a power savings mode by turning off power to the unit. Core hardware will automatically power down the AltiVec unit after no AltiVec instructions have executed in N cycles. The AltiVec power-control is triggered by hardware. Signed-off-by: Wang Dongsheng Signed-off-by: Scott Wood --- arch/powerpc/kernel/cpu_setup_fsl_booke.S | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/arch/powerpc/kernel/cpu_setup_fsl_booke.S b/arch/powerpc/kernel/cpu_setup_fsl_booke.S index fa6862db8a02..26c09db2ec20 100644 --- a/arch/powerpc/kernel/cpu_setup_fsl_booke.S +++ b/arch/powerpc/kernel/cpu_setup_fsl_booke.S @@ -53,6 +53,25 @@ _GLOBAL(__e500_dcache_setup) isync blr +/* + * FIXME - we haven't yet done testing to determine a reasonable default + * value for AV_WAIT_IDLE_BIT. + */ +#define AV_WAIT_IDLE_BIT 50 /* 1ms, TB frequency is 41.66MHZ */ +_GLOBAL(setup_altivec_idle) + mfspr r3, SPRN_PWRMGTCR0 + + /* Enable Altivec Idle */ + oris r3, r3, PWRMGTCR0_AV_IDLE_PD_EN@h + li r11, AV_WAIT_IDLE_BIT + + /* Set Automatic AltiVec Idle Count */ + rlwimi r3, r11, PWRMGTCR0_AV_IDLE_CNT_SHIFT, PWRMGTCR0_AV_IDLE_CNT + + mtspr SPRN_PWRMGTCR0, r3 + + blr + _GLOBAL(__setup_cpu_e6500) mflr r6 #ifdef CONFIG_PPC64 @@ -64,6 +83,7 @@ _GLOBAL(__setup_cpu_e6500) bl .setup_lrat_ivor 1: #endif + bl setup_altivec_idle bl __setup_cpu_e5500 mtlr r6 blr @@ -131,6 +151,7 @@ _GLOBAL(__restore_cpu_e6500) beq 1f bl .setup_lrat_ivor 1: + bl .setup_altivec_idle bl __restore_cpu_e5500 mtlr r5 blr