From c4236d2e7913d18d058a018f0d19473eb6a11a3c Mon Sep 17 00:00:00 2001 From: Peter 'p2' De Schrijver Date: Mon, 20 Dec 2010 14:05:07 -0600 Subject: [PATCH] OMAP3630: PM: Disable L2 cache while invalidating L2 cache While coming out of MPU OSWR/OFF states, L2 controller is reseted. The reset behavior is implementation specific as per ARMv7 TRM and hence $L2 needs to be invalidated before it's use. Since the AUXCTRL register is also reconfigured, disable L2 cache before invalidating it and re-enables it afterwards. This is as per Cortex-A8 ARM documentation. Currently this is identified as being needed on OMAP3630 as the disable/enable is done from "public side" while, on OMAP3430, this is done in the "secure side". Cc: Kevin Hilman Cc: Tony Lindgren Acked-by: Jean Pihet Acked-by: Santosh Shilimkar [nm@ti.com: ported to 2.6.37-rc2, added hooks to enable the logic only on 3630] Signed-off-by: Nishanth Menon Signed-off-by: Eduardo Valentin Signed-off-by: Peter 'p2' De Schrijver Signed-off-by: Kevin Hilman --- arch/arm/mach-omap2/pm.h | 2 ++ arch/arm/mach-omap2/pm34xx.c | 5 ++++- arch/arm/mach-omap2/sleep34xx.S | 30 ++++++++++++++++++++++++++++++ 3 files changed, 36 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h index 8d9aa3e0f635..5e0bee961850 100644 --- a/arch/arm/mach-omap2/pm.h +++ b/arch/arm/mach-omap2/pm.h @@ -90,8 +90,10 @@ extern unsigned int omap34xx_cpu_suspend_sz; #if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3) extern u16 pm34xx_errata; #define IS_PM34XX_ERRATUM(id) (pm34xx_errata & (id)) +extern void enable_omap3630_toggle_l2_on_restore(void); #else #define IS_PM34XX_ERRATUM(id) 0 +static inline void enable_omap3630_toggle_l2_on_restore(void) { } #endif /* defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3) */ #endif diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c index 7dbc00005464..96e309d44e14 100644 --- a/arch/arm/mach-omap2/pm34xx.c +++ b/arch/arm/mach-omap2/pm34xx.c @@ -996,8 +996,11 @@ void omap_push_sram_idle(void) static void __init pm_errata_configure(void) { - if (cpu_is_omap3630()) + if (cpu_is_omap3630()) { pm34xx_errata |= PM_RTA_ERRATUM_i608; + /* Enable the l2 cache toggling in sleep logic */ + enable_omap3630_toggle_l2_on_restore(); + } } static int __init omap3_pm_init(void) diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S index 4abf447fddfc..50887c75a3b8 100644 --- a/arch/arm/mach-omap2/sleep34xx.S +++ b/arch/arm/mach-omap2/sleep34xx.S @@ -110,6 +110,19 @@ ENTRY(get_omap3630_restore_pointer) ENTRY(get_omap3630_restore_pointer_sz) .word . - get_omap3630_restore_pointer + .text +/* + * L2 cache needs to be toggled for stable OFF mode functionality on 3630. + * This function sets up a fflag that will allow for this toggling to take + * place on 3630. Hopefully some version in the future maynot need this + */ +ENTRY(enable_omap3630_toggle_l2_on_restore) + stmfd sp!, {lr} @ save registers on stack + /* Setup so that we will disable and enable l2 */ + mov r1, #0x1 + str r1, l2dis_3630 + ldmfd sp!, {pc} @ restore regs and return + .text /* Function call to get the restore pointer for for ES3 to resume from OFF */ ENTRY(get_es3_restore_pointer) @@ -283,6 +296,14 @@ restore: moveq r9, #0x3 @ MPU OFF => L1 and L2 lost movne r9, #0x1 @ Only L1 and L2 lost => avoid L2 invalidation bne logic_l1_restore + + ldr r0, l2dis_3630 + cmp r0, #0x1 @ should we disable L2 on 3630? + bne skipl2dis + mrc p15, 0, r0, c1, c0, 1 + bic r0, r0, #2 @ disable L2 cache + mcr p15, 0, r0, c1, c0, 1 +skipl2dis: ldr r0, control_stat ldr r1, [r0] and r1, #0x700 @@ -343,6 +364,13 @@ smi: .word 0xE1600070 @ Call SMI monitor (smieq) mov r12, #0x2 .word 0xE1600070 @ Call SMI monitor (smieq) logic_l1_restore: + ldr r1, l2dis_3630 + cmp r1, #0x1 @ Do we need to re-enable L2 on 3630? + bne skipl2reen + mrc p15, 0, r1, c1, c0, 1 + orr r1, r1, #2 @ re-enable L2 cache + mcr p15, 0, r1, c1, c0, 1 +skipl2reen: mov r1, #0 /* Invalidate all instruction caches to PoU * and flush branch target cache */ @@ -679,6 +707,8 @@ control_mem_rta: .word CONTROL_MEM_RTA_CTRL kernel_flush: .word v7_flush_dcache_all +l2dis_3630: + .word 0 /* * When exporting to userspace while the counters are in SRAM, * these 2 words need to be at the end to facilitate retrival! -- 2.20.1