From ac0d98cd557e0939bd0f10ff68e2e648a74bbea6 Mon Sep 17 00:00:00 2001 From: Akshay Saraswat Date: Fri, 20 Feb 2015 13:27:12 +0530 Subject: Exynos542x: CPU: Power down all secondary cores This patch adds code to shutdown secondary cores. When U-boot comes up, all secondary cores appear powered on, which is undesirable and causes side effects while initializing these cores in kernel. Secondary core power down happens in following steps: Step-1: After Exynos power-on, primary core starts executing first. Step-2: In iROM code every core has to check 2 flags i.e. addresses 0x02020028 & 0x02020004. Step-3: Initially 0x02020028 is 0 for all cores and 0x02020004 has a jump address for primary core and 0 for all secondary cores. Step-4: Therefore, primary core follows normal iROM execution and jumps to BL1 eventually, whereas all secondary cores enter WFE. Step-5: When primary core comes into function secondary_cores_configure, it puts pointer to function power_down_core into 0x02020004 and provides DSB and SEV for all cores so that they may come out of WFE and jump to power_down_core function. Step-6: And ultimately because of power_down_core all secondary cores shut-down. Signed-off-by: Kimoon Kim Signed-off-by: Akshay Saraswat Signed-off-by: Minkyu Kang --- arch/arm/cpu/armv7/exynos/exynos5_setup.h | 3 ++ arch/arm/cpu/armv7/exynos/lowlevel_init.c | 69 +++++++++++++++++++++++++++++++ 2 files changed, 72 insertions(+) (limited to 'arch/arm/cpu') diff --git a/arch/arm/cpu/armv7/exynos/exynos5_setup.h b/arch/arm/cpu/armv7/exynos/exynos5_setup.h index 2eea48a..9073f50 100644 --- a/arch/arm/cpu/armv7/exynos/exynos5_setup.h +++ b/arch/arm/cpu/armv7/exynos/exynos5_setup.h @@ -700,6 +700,9 @@ #define CLK_DIV_CPERI1_VAL NOT_AVAILABLE #else + +#define CPU_CONFIG_STATUS_OFFSET 0x80 +#define CPU_RST_FLAG_VAL 0xFCBA0D10 #define PAD_RETENTION_DRAM_COREBLK_VAL 0x10000000 /* APLL_CON1 */ diff --git a/arch/arm/cpu/armv7/exynos/lowlevel_init.c b/arch/arm/cpu/armv7/exynos/lowlevel_init.c index 83e1dcf..e36f2fa 100644 --- a/arch/arm/cpu/armv7/exynos/lowlevel_init.c +++ b/arch/arm/cpu/armv7/exynos/lowlevel_init.c @@ -31,7 +31,9 @@ #include #include #include +#include #include "common_setup.h" +#include "exynos5_setup.h" /* These are the things we can do during low-level init */ enum { @@ -42,6 +44,68 @@ enum { DO_POWER = 1 << 4, }; +#ifdef CONFIG_EXYNOS5420 +/* + * Pointer to this function is stored in iRam which is used + * for jump and power down of a specific core. + */ +static void power_down_core(void) +{ + uint32_t tmp, core_id, core_config; + + /* Get the unique core id */ + /* + * Multiprocessor Affinity Register + * [11:8] Cluster ID + * [1:0] CPU ID + */ + mrc_mpafr(core_id); + tmp = core_id & 0x3; + core_id = (core_id >> 6) & ~3; + core_id |= tmp; + core_id &= 0x3f; + + /* Set the status of the core to low */ + core_config = (core_id * CPU_CONFIG_STATUS_OFFSET); + core_config += EXYNOS5420_CPU_CONFIG_BASE; + writel(0x0, core_config); + + /* Core enter WFI */ + wfi(); +} + +/* + * Configurations for secondary cores are inapt at this stage. + * Reconfigure secondary cores. Shutdown and change the status + * of all cores except the primary core. + */ +static void secondary_cores_configure(void) +{ + uint32_t core_id; + + /* Store jump address for power down of secondary cores */ + writel((uint32_t)&power_down_core, CONFIG_PHY_IRAM_BASE + 0x4); + + /* Need all core power down check */ + dsb(); + sev(); + + /* + * Power down all cores(secondary) while primary core must + * wait for all cores to go down. + */ + for (core_id = 1; core_id != CONFIG_CORE_COUNT; core_id++) { + while ((readl(EXYNOS5420_CPU_STATUS_BASE + + (core_id * CPU_CONFIG_STATUS_OFFSET)) + & 0xff) != 0x0) { + isb(); + sev(); + } + isb(); + } +} +#endif + int do_lowlevel_init(void) { uint32_t reset_status; @@ -49,6 +113,11 @@ int do_lowlevel_init(void) arch_cpu_init(); +#ifdef CONFIG_EXYNOS5420 + /* Reconfigure secondary cores */ + secondary_cores_configure(); +#endif + reset_status = get_reset_status(); switch (reset_status) { -- cgit v1.1 From 67a0652c47ec568ea274f5ff0303c9bba8ceddbf Mon Sep 17 00:00:00 2001 From: Akshay Saraswat Date: Fri, 20 Feb 2015 13:27:15 +0530 Subject: Exynos542x: Add workaround for exynos iROM errata iROM logic provides undesired jump address for CPU2. This patch adds a programmable susbstitute for a part of iROM logic which wakes up cores and provides jump addresses. This patch creates a logic to make all secondary cores jump to a particular address which evades the possibility of CPU2 jumping to wrong address and create undesired results. Logic of the workaround: Step-1: iROM code checks value at address 0x2020028. Step-2: If value is 0xc9cfcfcf, it jumps to the address (0x202000+CPUid*4), else, it continues executing normally. Step-3: Primary core puts secondary cores in WFE and store 0xc9cfcfcf in 0x2020028 and jump address (pointer to function low_power_start) in (0x202000+CPUid*4). Step-4: When secondary cores recieve event signal they jump to this address and continue execution. Signed-off-by: Kimoon Kim Signed-off-by: Akshay Saraswat Reviewed-by: Simon Glass Tested-by: Simon Glass Signed-off-by: Minkyu Kang --- arch/arm/cpu/armv7/exynos/Makefile | 2 + arch/arm/cpu/armv7/exynos/lowlevel_init.c | 86 ++++++++++++++++---- arch/arm/cpu/armv7/exynos/sec_boot.S | 128 ++++++++++++++++++++++++++++++ 3 files changed, 200 insertions(+), 16 deletions(-) create mode 100644 arch/arm/cpu/armv7/exynos/sec_boot.S (limited to 'arch/arm/cpu') diff --git a/arch/arm/cpu/armv7/exynos/Makefile b/arch/arm/cpu/armv7/exynos/Makefile index e207bd6..8542f89 100644 --- a/arch/arm/cpu/armv7/exynos/Makefile +++ b/arch/arm/cpu/armv7/exynos/Makefile @@ -7,6 +7,8 @@ obj-y += clock.o power.o soc.o system.o pinmux.o tzpc.o +obj-$(CONFIG_EXYNOS5420) += sec_boot.o + ifdef CONFIG_SPL_BUILD obj-$(CONFIG_EXYNOS5) += clock_init_exynos5.o obj-$(CONFIG_EXYNOS5) += dmc_common.o dmc_init_ddr3.o diff --git a/arch/arm/cpu/armv7/exynos/lowlevel_init.c b/arch/arm/cpu/armv7/exynos/lowlevel_init.c index e36f2fa..b94e49f 100644 --- a/arch/arm/cpu/armv7/exynos/lowlevel_init.c +++ b/arch/arm/cpu/armv7/exynos/lowlevel_init.c @@ -32,6 +32,7 @@ #include #include #include +#include #include "common_setup.h" #include "exynos5_setup.h" @@ -46,6 +47,61 @@ enum { #ifdef CONFIG_EXYNOS5420 /* + * Power up secondary CPUs. + */ +static void secondary_cpu_start(void) +{ + v7_enable_smp(EXYNOS5420_INFORM_BASE); + svc32_mode_en(); + set_pc(CONFIG_EXYNOS_RELOCATE_CODE_BASE); +} + +/* + * This is the entry point of hotplug-in and + * cluster switching. + */ +static void low_power_start(void) +{ + uint32_t val, reg_val; + + reg_val = readl(EXYNOS5420_SPARE_BASE); + if (reg_val != CPU_RST_FLAG_VAL) { + writel(0x0, CONFIG_LOWPOWER_FLAG); + set_pc(0x0); + } + + reg_val = readl(CONFIG_PHY_IRAM_BASE + 0x4); + if (reg_val != (uint32_t)&low_power_start) { + /* Store jump address as low_power_start if not present */ + writel((uint32_t)&low_power_start, CONFIG_PHY_IRAM_BASE + 0x4); + dsb(); + sev(); + } + + /* Set the CPU to SVC32 mode */ + svc32_mode_en(); + v7_enable_l2_hazard_detect(); + + /* Invalidate L1 & TLB */ + val = 0x0; + mcr_tlb(val); + mcr_icache(val); + + /* Disable MMU stuff and caches */ + mrc_sctlr(val); + + val &= ~((0x2 << 12) | 0x7); + val |= ((0x1 << 12) | (0x8 << 8) | 0x2); + mcr_sctlr(val); + + /* CPU state is hotplug or reset */ + secondary_cpu_start(); + + /* Core should not enter into WFI here */ + wfi(); +} + +/* * Pointer to this function is stored in iRam which is used * for jump and power down of a specific core. */ @@ -81,29 +137,25 @@ static void power_down_core(void) */ static void secondary_cores_configure(void) { - uint32_t core_id; + /* Setup L2 cache */ + v7_enable_l2_hazard_detect(); - /* Store jump address for power down of secondary cores */ + /* Clear secondary boot iRAM base */ + writel(0x0, (CONFIG_EXYNOS_RELOCATE_CODE_BASE + 0x1C)); + + /* set lowpower flag and address */ + writel(CPU_RST_FLAG_VAL, CONFIG_LOWPOWER_FLAG); + writel((uint32_t)&low_power_start, CONFIG_LOWPOWER_ADDR); + writel(CPU_RST_FLAG_VAL, EXYNOS5420_SPARE_BASE); + /* Store jump address for power down */ writel((uint32_t)&power_down_core, CONFIG_PHY_IRAM_BASE + 0x4); /* Need all core power down check */ dsb(); sev(); - - /* - * Power down all cores(secondary) while primary core must - * wait for all cores to go down. - */ - for (core_id = 1; core_id != CONFIG_CORE_COUNT; core_id++) { - while ((readl(EXYNOS5420_CPU_STATUS_BASE - + (core_id * CPU_CONFIG_STATUS_OFFSET)) - & 0xff) != 0x0) { - isb(); - sev(); - } - isb(); - } } + +extern void relocate_wait_code(void); #endif int do_lowlevel_init(void) @@ -114,6 +166,8 @@ int do_lowlevel_init(void) arch_cpu_init(); #ifdef CONFIG_EXYNOS5420 + relocate_wait_code(); + /* Reconfigure secondary cores */ secondary_cores_configure(); #endif diff --git a/arch/arm/cpu/armv7/exynos/sec_boot.S b/arch/arm/cpu/armv7/exynos/sec_boot.S new file mode 100644 index 0000000..dfc3455 --- /dev/null +++ b/arch/arm/cpu/armv7/exynos/sec_boot.S @@ -0,0 +1,128 @@ +/* + * Copyright (C) 2013 Samsung Electronics + * Akshay Saraswat + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include + + .globl relocate_wait_code +relocate_wait_code: + adr r0, code_base @ r0: source address (start) + adr r1, code_end @ r1: source address (end) + ldr r2, =0x02073000 @ r2: target address +1: + ldmia r0!, {r3-r6} + stmia r2!, {r3-r6} + cmp r0, r1 + blt 1b + b code_end + .ltorg +/* + * Secondary core waits here until Primary wake it up. + * Below code is copied to CONFIG_EXYNOS_RELOCATE_CODE_BASE. + * This is a workaround code which is supposed to act as a + * substitute/supplement to the iROM code. + * + * This workaround code is relocated to the address 0x02073000 + * because that comes out to be the last 4KB of the iRAM + * (Base Address - 0x02020000, Limit Address - 0x020740000). + * + * U-boot and kernel are aware of this code and flags by the simple + * fact that we are implementing a workaround in the last 4KB + * of the iRAM and we have already defined these flag and address + * values in both kernel and U-boot for our use. + */ +code_base: + b 1f +/* + * These addresses are being used as flags in u-boot and kernel. + * + * Jump address for resume and flag to check for resume/reset: + * Resume address - 0x2073008 + * Resume flag - 0x207300C + * + * Jump address for cluster switching: + * Switch address - 0x2073018 + * + * Jump address for core hotplug: + * Hotplug address - 0x207301C + * + * Jump address for C2 state (Reserved for future not being used right now): + * C2 address - 0x2073024 + * + * Managed per core status for the active cluster: + * CPU0 state - 0x2073028 + * CPU1 state - 0x207302C + * CPU2 state - 0x2073030 + * CPU3 state - 0x2073034 + * + * Managed per core GIC status for the active cluster: + * CPU0 gic state - 0x2073038 + * CPU1 gic state - 0x207303C + * CPU2 gic state - 0x2073040 + * CPU3 gic state - 0x2073044 + * + * Logic of the code: + * Step-1: Read current CPU status. + * Step-2: If it's a resume then continue, else jump to step 4. + * Step-3: Clear inform1 PMU register and jump to inform0 value. + * Step-4: If it's a switch, C2 or reset, get the hotplug address. + * Step-5: If address is not available, enter WFE. + * Step-6: If address is available, jump to that address. + */ + nop @ for backward compatibility + .word 0x0 @ REG0: RESUME_ADDR + .word 0x0 @ REG1: RESUME_FLAG + .word 0x0 @ REG2 + .word 0x0 @ REG3 +_switch_addr: + .word 0x0 @ REG4: SWITCH_ADDR +_hotplug_addr: + .word 0x0 @ REG5: CPU1_BOOT_REG + .word 0x0 @ REG6 +_c2_addr: + .word 0x0 @ REG7: REG_C2_ADDR +_cpu_state: + .word 0x1 @ CPU0_STATE : RESET + .word 0x2 @ CPU1_STATE : SECONDARY RESET + .word 0x2 @ CPU2_STATE : SECONDARY RESET + .word 0x2 @ CPU3_STATE : SECONDARY RESET +_gic_state: + .word 0x0 @ CPU0 - GICD_IGROUPR0 + .word 0x0 @ CPU1 - GICD_IGROUPR0 + .word 0x0 @ CPU2 - GICD_IGROUPR0 + .word 0x0 @ CPU3 - GICD_IGROUPR0 +1: + adr r0, _cpu_state + mrc p15, 0, r7, c0, c0, 5 @ read MPIDR + and r7, r7, #0xf @ r7 = cpu id +/* Read the current cpu state */ + ldr r10, [r0, r7, lsl #2] +svc_entry: + tst r10, #(1 << 4) + adrne r0, _switch_addr + bne wait_for_addr +/* Clear INFORM1 */ + ldr r0, =(0x10040000 + 0x804) + ldr r1, [r0] + cmp r1, #0x0 + movne r1, #0x0 + strne r1, [r0] +/* Get INFORM0 */ + ldrne r1, =(0x10040000 + 0x800) + ldrne pc, [r1] + tst r10, #(1 << 0) + ldrne pc, =0x23e00000 + adr r0, _hotplug_addr +wait_for_addr: + ldr r1, [r0] + cmp r1, #0x0 + bxne r1 + wfe + b wait_for_addr + .ltorg +code_end: + mov pc, lr -- cgit v1.1 From f0f76b0a4c7181b2cbde39ec04eac8973cd4ad1f Mon Sep 17 00:00:00 2001 From: Akshay Saraswat Date: Fri, 20 Feb 2015 13:27:16 +0530 Subject: Exynos542x: cache: Disable clean/evict push to external L2 Auxiliary Control Register provides configuration and control options for the L2 memory system. Bit 3 of L2ACTLR stands for clean/evict push to external. Setting bit 3 disables clean/evict which is what this patch intends to do. Signed-off-by: Akshay Saraswat Reviewed-by: Simon Glass Tested-by: Simon Glass Signed-off-by: Minkyu Kang --- arch/arm/cpu/armv7/exynos/soc.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) (limited to 'arch/arm/cpu') diff --git a/arch/arm/cpu/armv7/exynos/soc.c b/arch/arm/cpu/armv7/exynos/soc.c index 8c7d7d8..427f54c 100644 --- a/arch/arm/cpu/armv7/exynos/soc.c +++ b/arch/arm/cpu/armv7/exynos/soc.c @@ -13,7 +13,9 @@ enum l2_cache_params { CACHE_TAG_RAM_SETUP = (1 << 9), CACHE_DATA_RAM_SETUP = (1 << 5), CACHE_TAG_RAM_LATENCY = (2 << 6), - CACHE_DATA_RAM_LATENCY = (2 << 0) + CACHE_DATA_RAM_LATENCY = (2 << 0), + CACHE_ENABLE_CLEAN_EVICT = (0 << 3), + CACHE_DISABLE_CLEAN_EVICT = (1 << 3) }; void reset_cpu(ulong addr) @@ -37,14 +39,28 @@ static void exynos5_set_l2cache_params(void) { unsigned int val = 0; + /* Read L2CTLR value */ asm volatile("mrc p15, 1, %0, c9, c0, 2\n" : "=r"(val)); + /* Set cache setup and latency cycles */ val |= CACHE_TAG_RAM_SETUP | CACHE_DATA_RAM_SETUP | 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)); + + /* Disable clean/evict push to external */ + val |= CACHE_DISABLE_CLEAN_EVICT; + + /* Write new vlaue to L2ACTLR */ + asm volatile("mcr p15, 1, %0, c15, c0, 0" : : "r" (val)); + } } /* -- cgit v1.1 From 7e514eef02d2508a19be13d3efdf747c4e7ef5c5 Mon Sep 17 00:00:00 2001 From: Akshay Saraswat Date: Fri, 20 Feb 2015 13:27:17 +0530 Subject: 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(-) (limited to 'arch/arm/cpu') diff --git a/arch/arm/cpu/armv7/exynos/lowlevel_init.c b/arch/arm/cpu/armv7/exynos/lowlevel_init.c index b94e49f..0504576 100644 --- a/arch/arm/cpu/armv7/exynos/lowlevel_init.c +++ b/arch/arm/cpu/armv7/exynos/lowlevel_init.c @@ -47,6 +47,42 @@ 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. */ static void secondary_cpu_start(void) @@ -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 427f54c..68eb8e7 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)); } /* -- cgit v1.1 From cecf2db23b256d84ed54e1442b646f07373e5caa Mon Sep 17 00:00:00 2001 From: Akshay Saraswat Date: Fri, 20 Feb 2015 13:27:18 +0530 Subject: Exynos542x: Fix secondary core booting for thumb When compiled SPL for Thumb secondary cores failed to boot at the kernel boot up. Only one core came up out of 4. This was happening because the code relocated to the address 0x02073000 by the primary core was an ARM asm code which was executed by the secondary cores as if it was a thumb code. This patch fixes the issue of secondary cores considering relocated code as Thumb instructions and not ARM instructions by jumping to the relocated with the help of "bx" ARM instruction. "bx" instruction changes the 5th bit of CPSR which allows execution unit to consider the following instructions as ARM instructions. 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 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/cpu') diff --git a/arch/arm/cpu/armv7/exynos/lowlevel_init.c b/arch/arm/cpu/armv7/exynos/lowlevel_init.c index 0504576..782ecd1 100644 --- a/arch/arm/cpu/armv7/exynos/lowlevel_init.c +++ b/arch/arm/cpu/armv7/exynos/lowlevel_init.c @@ -89,7 +89,7 @@ static void secondary_cpu_start(void) { v7_enable_smp(EXYNOS5420_INFORM_BASE); svc32_mode_en(); - set_pc(CONFIG_EXYNOS_RELOCATE_CODE_BASE); + branch_bx(CONFIG_EXYNOS_RELOCATE_CODE_BASE); } /* -- cgit v1.1 From c8fd8e66cdd9bf8b4fe78eaaa9bc1000fa60ae85 Mon Sep 17 00:00:00 2001 From: Akshay Saraswat Date: Fri, 20 Feb 2015 13:27:19 +0530 Subject: Exynos542x: Make A7s boot with thumb-mode U-Boot on warm reset On warm reset, all cores jump to the low_power_start function because iRAM data is retained and because while executing iROM code all cores find the jump flag 0x02020028 set. In low_power_start, cores check the reset status and if true they clear the jump flag and jump back to 0x0. The A7 cores do jump to 0x0 but consider following instructions as a Thumb instructions which in turn makes them loop inside the iROM code instead of jumping to power_down_core. This issue is fixed by replacing the "mov pc" instruction with a "bx" instruction which switches state along with the jump to make the execution unit consider the branch target as an ARM instruction. 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 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/cpu') diff --git a/arch/arm/cpu/armv7/exynos/lowlevel_init.c b/arch/arm/cpu/armv7/exynos/lowlevel_init.c index 782ecd1..329ab0c 100644 --- a/arch/arm/cpu/armv7/exynos/lowlevel_init.c +++ b/arch/arm/cpu/armv7/exynos/lowlevel_init.c @@ -103,7 +103,7 @@ static void low_power_start(void) reg_val = readl(EXYNOS5420_SPARE_BASE); if (reg_val != CPU_RST_FLAG_VAL) { writel(0x0, CONFIG_LOWPOWER_FLAG); - set_pc(0x0); + branch_bx(0x0); } reg_val = readl(CONFIG_PHY_IRAM_BASE + 0x4); -- cgit v1.1 From 306f527eff269e48a98c9d83016df6d6877dbb6a Mon Sep 17 00:00:00 2001 From: Doug Anderson Date: Fri, 20 Feb 2015 13:27:20 +0530 Subject: Exynos: Fix L2 cache timings on Exynos5420 and Exynos5800 It was found that the L2 cache timings that we had before could cause freezes and hangs. We should make things more robust with better timings. Currently the production ChromeOS kernel applies these timings, but it's nice to fixup firmware too (and upstream probably won't take our kernel hacks). This also provides a big cleanup of the L2 cache init code avoiding some duplication. The way things used to work: * low_power_start() was installed by the SPL (both at boot and resume time) and left resident in iRAM for the kernel to use when bringing up additional CPUs. It used configure_l2_ctlr() and configure_l2_actlr() when it detected it was on an A15. This was needed (despite the L2 cache registers being shared among all A15s) because we might have been the first man in after the whole A15 cluster was shutdown. * secondary_cores_configure() was called on at boot time and at resume time. Strangely this called configure_l2_ctlr() but not configure_l2_actlr() which was almost certainly wrong. Given that we'll call both (see next bullet) later in the boot process it didn't matter for normal boot, but I guess this is how L2 cache settings got set on 5420/5800 (but not 5250?) at resume time. * exynos5_set_l2cache_params() was called as part of cache enablement. This should happen at boot time (normally in the SPL except for USB boot where it happens in main U-Boot). Note that the old code wasn't setting ECC/parity in the cache enablement code but we happened to get it anyway because we'd call secondary_cores_configure() at boot time. For resume time we'd get it anyway when the 2nd A15 core came up. Let's make this a whole lot simpler. Now we always set these parameters in the same place for all boots and use the same code for setting up secondary CPUs. Intended net effects of this change (other than cleanup): * Timings go from before: data: 0 cycle setup, 3 cycles (0x2) latency tag: 0 cycle setup, 3 cycles (0x2) latency after: data: 1 cycle setup, 4 cycles (0x3) latency tag: 1 cycle setup, 4 cycles (0x3) latency * L2ACTLR is properly initted on 5420/5800 in all cases. One note is that we're still relying on luck to keep low_power_start() working. The compiler is being nice and not storing anything on the stack. Another note is that on its own this patch won't help to fix cache settings in an RW U-Boot update where we still have the RO SPL. The plan for that is: * Have RW U-Boot re-init the cache right before calling the kernel (after it has turned the L2 cache off). This is why the functions are in a header file instead of lowlevel_init.c. * Have the kernel save the L2 cache settings of the boot CPU and apply them to all other CPUs. We get a little lucky here because the old code was using "|=" to modify the registers and all of the bits that it's setting are also present in the new settings (!). That means that when the 2nd CPU in the A15 cluster comes up it doesn't actually mess up the settings of the 1st CPU in the A15 cluster. An alternative option is to have the kernel write its own low_power_start() code. Signed-off-by: Doug Anderson Signed-off-by: Akshay Saraswat Signed-off-by: Minkyu Kang --- arch/arm/cpu/armv7/exynos/common_setup.h | 62 +++++++++++++++++++++++++++++++ arch/arm/cpu/armv7/exynos/lowlevel_init.c | 55 ++++++++------------------- arch/arm/cpu/armv7/exynos/soc.c | 53 -------------------------- 3 files changed, 77 insertions(+), 93 deletions(-) (limited to 'arch/arm/cpu') diff --git a/arch/arm/cpu/armv7/exynos/common_setup.h b/arch/arm/cpu/armv7/exynos/common_setup.h index e6318c0..5235abb 100644 --- a/arch/arm/cpu/armv7/exynos/common_setup.h +++ b/arch/arm/cpu/armv7/exynos/common_setup.h @@ -23,6 +23,8 @@ * MA 02111-1307 USA */ +#include + #define DMC_OFFSET 0x10000 /* @@ -43,3 +45,63 @@ void system_clock_init(void); int do_lowlevel_init(void); void sdelay(unsigned long); + +enum l2_cache_params { + CACHE_DATA_RAM_LATENCY_2_CYCLES = (2 << 0), + CACHE_DATA_RAM_LATENCY_3_CYCLES = (3 << 0), + CACHE_DISABLE_CLEAN_EVICT = (1 << 3), + CACHE_DATA_RAM_SETUP = (1 << 5), + CACHE_TAG_RAM_LATENCY_2_CYCLES = (2 << 6), + CACHE_TAG_RAM_LATENCY_3_CYCLES = (3 << 6), + CACHE_ENABLE_HAZARD_DETECT = (1 << 7), + CACHE_TAG_RAM_SETUP = (1 << 9), + CACHE_ECC_AND_PARITY = (1 << 21), + CACHE_ENABLE_FORCE_L2_LOGIC = (1 << 27) +}; + + +#ifndef CONFIG_SYS_L2CACHE_OFF +/* + * Configure L2CTLR to get timings that keep us from hanging/crashing. + * + * Must be inline here since low_power_start() is called without a + * stack (!). + */ +static inline void configure_l2_ctlr(void) +{ + uint32_t val; + + mrc_l2_ctlr(val); + + val |= CACHE_TAG_RAM_SETUP | + CACHE_DATA_RAM_SETUP | + CACHE_TAG_RAM_LATENCY_2_CYCLES | + CACHE_DATA_RAM_LATENCY_2_CYCLES; + + if (proid_is_exynos5420() || proid_is_exynos5800()) { + val |= CACHE_ECC_AND_PARITY | + CACHE_TAG_RAM_LATENCY_3_CYCLES | + CACHE_DATA_RAM_LATENCY_3_CYCLES; + } + + mcr_l2_ctlr(val); +} + +/* + * Configure L2ACTLR. + * + * Must be inline here since low_power_start() is called without a + * stack (!). + */ +static inline void configure_l2_actlr(void) +{ + uint32_t val; + + if (proid_is_exynos5420() || proid_is_exynos5800()) { + mrc_l2_aux_ctlr(val); + val |= CACHE_ENABLE_FORCE_L2_LOGIC | + CACHE_DISABLE_CLEAN_EVICT; + mcr_l2_aux_ctlr(val); + } +} +#endif diff --git a/arch/arm/cpu/armv7/exynos/lowlevel_init.c b/arch/arm/cpu/armv7/exynos/lowlevel_init.c index 329ab0c..120aaf8 100644 --- a/arch/arm/cpu/armv7/exynos/lowlevel_init.c +++ b/arch/arm/cpu/armv7/exynos/lowlevel_init.c @@ -47,42 +47,6 @@ 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. */ static void secondary_cpu_start(void) @@ -185,10 +149,6 @@ 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 */ writel(0x0, (CONFIG_EXYNOS_RELOCATE_CODE_BASE + 0x1C)); @@ -214,6 +174,21 @@ int do_lowlevel_init(void) arch_cpu_init(); +#ifndef CONFIG_SYS_L2CACHE_OFF + /* + * Init L2 cache parameters here for use by boot and resume + * + * These are here instead of in v7_outer_cache_enable() so that the + * L2 cache settings get properly set even at resume time or if we're + * running U-Boot with the cache off. The kernel still needs us to + * set these for it. + */ + configure_l2_ctlr(); + configure_l2_actlr(); + dsb(); + isb(); +#endif + #ifdef CONFIG_EXYNOS5420 relocate_wait_code(); diff --git a/arch/arm/cpu/armv7/exynos/soc.c b/arch/arm/cpu/armv7/exynos/soc.c index 68eb8e7..0f116b1 100644 --- a/arch/arm/cpu/armv7/exynos/soc.c +++ b/arch/arm/cpu/armv7/exynos/soc.c @@ -9,15 +9,6 @@ #include #include -enum l2_cache_params { - CACHE_TAG_RAM_SETUP = (1 << 9), - CACHE_DATA_RAM_SETUP = (1 << 5), - CACHE_TAG_RAM_LATENCY = (2 << 6), - CACHE_DATA_RAM_LATENCY = (2 << 0), - CACHE_ENABLE_CLEAN_EVICT = (0 << 3), - CACHE_DISABLE_CLEAN_EVICT = (1 << 3) -}; - void reset_cpu(ulong addr) { writel(0x1, samsung_get_base_swreset()); @@ -30,47 +21,3 @@ void enable_caches(void) dcache_enable(); } #endif - -#ifndef CONFIG_SYS_L2CACHE_OFF -/* - * Set L2 cache parameters - */ -static void exynos5_set_l2cache_params(void) -{ - unsigned int l2ctlr = 0, l2actlr = 0; - - /* Read L2CTLR value */ - asm volatile("mrc p15, 1, %0, c9, c0, 2\n" : "=r"(l2ctlr)); - - /* Set cache latency cycles */ - l2ctlr |= CACHE_TAG_RAM_LATENCY | - CACHE_DATA_RAM_LATENCY; - - if (proid_is_exynos5420() || proid_is_exynos5800()) { - /* Read L2ACTLR value */ - asm volatile("mrc p15, 1, %0, c15, c0, 0" : "=r" (l2actlr)); - - /* Disable clean/evict push to external */ - l2actlr |= CACHE_DISABLE_CLEAN_EVICT; - - /* Write new vlaue to L2ACTLR */ - 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)); -} - -/* - * Sets L2 cache related parameters before enabling data cache - */ -void v7_outer_cache_enable(void) -{ - if (cpu_is_exynos5()) - exynos5_set_l2cache_params(); -} -#endif -- cgit v1.1