From 7e514eef02d2508a19be13d3efdf747c4e7ef5c5 Mon Sep 17 00:00:00 2001 From: Akshay Saraswat Date: Fri, 20 Feb 2015 13:27:17 +0530 Subject: [PATCH] Exynos542x: add L2 control register configuration This patch does 3 things: 1. Enables ECC by setting 21st bit of L2CTLR. 2. Restore data and tag RAM latencies to 3 cycles because iROM sets 0x3000400 L2CTLR value during switching. 3. Disable clean/evict push to external by setting 3rd bit of L2ACTLR. We need to restore this here due to switching. Signed-off-by: Abhilash Kesavan Signed-off-by: Akshay Saraswat Reviewed-by: Simon Glass Tested-by: Simon Glass Signed-off-by: Minkyu Kang --- arch/arm/cpu/armv7/exynos/lowlevel_init.c | 51 ++++++++++++++++++++++- arch/arm/cpu/armv7/exynos/soc.c | 26 ++++++------ 2 files changed, 64 insertions(+), 13 deletions(-) diff --git a/arch/arm/cpu/armv7/exynos/lowlevel_init.c b/arch/arm/cpu/armv7/exynos/lowlevel_init.c index b94e49f849..050457641e 100644 --- a/arch/arm/cpu/armv7/exynos/lowlevel_init.c +++ b/arch/arm/cpu/armv7/exynos/lowlevel_init.c @@ -46,6 +46,42 @@ enum { }; #ifdef CONFIG_EXYNOS5420 +/* + * Enable ECC by setting L2CTLR[21]. + * Set L2CTLR[7] to make tag ram latency 3 cycles and + * set L2CTLR[1] to make data ram latency 3 cycles. + * We need to make RAM latency of 3 cycles here because cores + * power ON and OFF while switching. And everytime a core powers + * ON, iROM provides it a default L2CTLR value 0x400 which stands + * for TAG RAM setup of 1 cycle. Hence, we face a need of + * restoring data and tag latency values. + */ +static void configure_l2_ctlr(void) +{ + uint32_t val; + + mrc_l2_ctlr(val); + val |= (1 << 21); + val |= (1 << 7); + val |= (1 << 1); + mcr_l2_ctlr(val); +} + +/* + * Set L2ACTLR[27] to prevent the clock generator from stopping + * the L2 logic clock. + * Set L2ACTLR[3] to disable clean/evict push to external. + */ +static void configure_l2_actlr(void) +{ + uint32_t val; + + mrc_l2_aux_ctlr(val); + val |= (1 << 27); + val |= (1 << 3); + mcr_l2_aux_ctlr(val); +} + /* * Power up secondary CPUs. */ @@ -80,7 +116,19 @@ static void low_power_start(void) /* Set the CPU to SVC32 mode */ svc32_mode_en(); - v7_enable_l2_hazard_detect(); + +#ifndef CONFIG_SYS_L2CACHE_OFF + /* Read MIDR for Primary Part Number */ + mrc_midr(val); + val = (val >> 4); + val &= 0xf; + + if (val == 0xf) { + configure_l2_ctlr(); + configure_l2_actlr(); + v7_enable_l2_hazard_detect(); + } +#endif /* Invalidate L1 & TLB */ val = 0x0; @@ -138,6 +186,7 @@ static void power_down_core(void) static void secondary_cores_configure(void) { /* Setup L2 cache */ + configure_l2_ctlr(); v7_enable_l2_hazard_detect(); /* Clear secondary boot iRAM base */ diff --git a/arch/arm/cpu/armv7/exynos/soc.c b/arch/arm/cpu/armv7/exynos/soc.c index 427f54c7e6..68eb8e7fc9 100644 --- a/arch/arm/cpu/armv7/exynos/soc.c +++ b/arch/arm/cpu/armv7/exynos/soc.c @@ -37,30 +37,32 @@ void enable_caches(void) */ static void exynos5_set_l2cache_params(void) { - unsigned int val = 0; + unsigned int l2ctlr = 0, l2actlr = 0; /* Read L2CTLR value */ - asm volatile("mrc p15, 1, %0, c9, c0, 2\n" : "=r"(val)); + asm volatile("mrc p15, 1, %0, c9, c0, 2\n" : "=r"(l2ctlr)); - /* Set cache setup and latency cycles */ - val |= CACHE_TAG_RAM_SETUP | - CACHE_DATA_RAM_SETUP | - CACHE_TAG_RAM_LATENCY | + /* Set cache latency cycles */ + l2ctlr |= CACHE_TAG_RAM_LATENCY | CACHE_DATA_RAM_LATENCY; - /* Write new vlaue to L2CTLR */ - asm volatile("mcr p15, 1, %0, c9, c0, 2\n" : : "r"(val)); - if (proid_is_exynos5420() || proid_is_exynos5800()) { /* Read L2ACTLR value */ - asm volatile("mrc p15, 1, %0, c15, c0, 0" : "=r" (val)); + asm volatile("mrc p15, 1, %0, c15, c0, 0" : "=r" (l2actlr)); /* Disable clean/evict push to external */ - val |= CACHE_DISABLE_CLEAN_EVICT; + l2actlr |= CACHE_DISABLE_CLEAN_EVICT; /* Write new vlaue to L2ACTLR */ - asm volatile("mcr p15, 1, %0, c15, c0, 0" : : "r" (val)); + asm volatile("mcr p15, 1, %0, c15, c0, 0" : : "r" (l2actlr)); + } else { + /* Set cache setup cycles */ + l2ctlr |= CACHE_TAG_RAM_SETUP | + CACHE_DATA_RAM_SETUP; } + + /* Write new vlaue to L2CTLR */ + asm volatile("mcr p15, 1, %0, c9, c0, 2\n" : : "r"(l2ctlr)); } /* -- 2.39.5