| /* |
| * Copyright (c) 2014 Samsung Electronics Co., Ltd. |
| * http://www.samsung.com |
| * |
| * arch/arm/mach-exynos/mcpm-exynos.c |
| * |
| * Based on arch/arm/mach-vexpress/dcscb.c |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/arm-cci.h> |
| #include <linux/delay.h> |
| #include <linux/io.h> |
| #include <linux/of_address.h> |
| #include <linux/syscore_ops.h> |
| |
| #include <asm/cputype.h> |
| #include <asm/cp15.h> |
| #include <asm/mcpm.h> |
| #include <asm/smp_plat.h> |
| |
| #include "regs-pmu.h" |
| #include "common.h" |
| |
| #define EXYNOS5420_CPUS_PER_CLUSTER 4 |
| #define EXYNOS5420_NR_CLUSTERS 2 |
| |
| #define EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN BIT(9) |
| #define EXYNOS5420_USE_ARM_CORE_DOWN_STATE BIT(29) |
| #define EXYNOS5420_USE_L2_COMMON_UP_STATE BIT(30) |
| |
| static void __iomem *ns_sram_base_addr; |
| |
| /* |
| * The common v7_exit_coherency_flush API could not be used because of the |
| * Erratum 799270 workaround. This macro is the same as the common one (in |
| * arch/arm/include/asm/cacheflush.h) except for the erratum handling. |
| */ |
| #define exynos_v7_exit_coherency_flush(level) \ |
| asm volatile( \ |
| "stmfd sp!, {fp, ip}\n\t"\ |
| "mrc p15, 0, r0, c1, c0, 0 @ get SCTLR\n\t" \ |
| "bic r0, r0, #"__stringify(CR_C)"\n\t" \ |
| "mcr p15, 0, r0, c1, c0, 0 @ set SCTLR\n\t" \ |
| "isb\n\t"\ |
| "bl v7_flush_dcache_"__stringify(level)"\n\t" \ |
| "mrc p15, 0, r0, c1, c0, 1 @ get ACTLR\n\t" \ |
| "bic r0, r0, #(1 << 6) @ disable local coherency\n\t" \ |
| /* Dummy Load of a device register to avoid Erratum 799270 */ \ |
| "ldr r4, [%0]\n\t" \ |
| "and r4, r4, #0\n\t" \ |
| "orr r0, r0, r4\n\t" \ |
| "mcr p15, 0, r0, c1, c0, 1 @ set ACTLR\n\t" \ |
| "isb\n\t" \ |
| "dsb\n\t" \ |
| "ldmfd sp!, {fp, ip}" \ |
| : \ |
| : "Ir" (pmu_base_addr + S5P_INFORM0) \ |
| : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \ |
| "r9", "r10", "lr", "memory") |
| |
| static int exynos_cpu_powerup(unsigned int cpu, unsigned int cluster) |
| { |
| unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER); |
| |
| pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); |
| if (cpu >= EXYNOS5420_CPUS_PER_CLUSTER || |
| cluster >= EXYNOS5420_NR_CLUSTERS) |
| return -EINVAL; |
| |
| if (!exynos_cpu_power_state(cpunr)) { |
| exynos_cpu_power_up(cpunr); |
| |
| /* |
| * This assumes the cluster number of the big cores(Cortex A15) |
| * is 0 and the Little cores(Cortex A7) is 1. |
| * When the system was booted from the Little core, |
| * they should be reset during power up cpu. |
| */ |
| if (cluster && |
| cluster == MPIDR_AFFINITY_LEVEL(cpu_logical_map(0), 1)) { |
| /* |
| * Before we reset the Little cores, we should wait |
| * the SPARE2 register is set to 1 because the init |
| * codes of the iROM will set the register after |
| * initialization. |
| */ |
| while (!pmu_raw_readl(S5P_PMU_SPARE2)) |
| udelay(10); |
| |
| pmu_raw_writel(EXYNOS5420_KFC_CORE_RESET(cpu), |
| EXYNOS_SWRESET); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int exynos_cluster_powerup(unsigned int cluster) |
| { |
| pr_debug("%s: cluster %u\n", __func__, cluster); |
| if (cluster >= EXYNOS5420_NR_CLUSTERS) |
| return -EINVAL; |
| |
| exynos_cluster_power_up(cluster); |
| return 0; |
| } |
| |
| static void exynos_cpu_powerdown_prepare(unsigned int cpu, unsigned int cluster) |
| { |
| unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER); |
| |
| pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); |
| BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER || |
| cluster >= EXYNOS5420_NR_CLUSTERS); |
| exynos_cpu_power_down(cpunr); |
| } |
| |
| static void exynos_cluster_powerdown_prepare(unsigned int cluster) |
| { |
| pr_debug("%s: cluster %u\n", __func__, cluster); |
| BUG_ON(cluster >= EXYNOS5420_NR_CLUSTERS); |
| exynos_cluster_power_down(cluster); |
| } |
| |
| static void exynos_cpu_cache_disable(void) |
| { |
| /* Disable and flush the local CPU cache. */ |
| exynos_v7_exit_coherency_flush(louis); |
| } |
| |
| static void exynos_cluster_cache_disable(void) |
| { |
| if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) { |
| /* |
| * On the Cortex-A15 we need to disable |
| * L2 prefetching before flushing the cache. |
| */ |
| asm volatile( |
| "mcr p15, 1, %0, c15, c0, 3\n\t" |
| "isb\n\t" |
| "dsb" |
| : : "r" (0x400)); |
| } |
| |
| /* Flush all cache levels for this cluster. */ |
| exynos_v7_exit_coherency_flush(all); |
| |
| /* |
| * Disable cluster-level coherency by masking |
| * incoming snoops and DVM messages: |
| */ |
| cci_disable_port_by_cpu(read_cpuid_mpidr()); |
| } |
| |
| static int exynos_wait_for_powerdown(unsigned int cpu, unsigned int cluster) |
| { |
| unsigned int tries = 100; |
| unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER); |
| |
| pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); |
| BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER || |
| cluster >= EXYNOS5420_NR_CLUSTERS); |
| |
| /* Wait for the core state to be OFF */ |
| while (tries--) { |
| if ((exynos_cpu_power_state(cpunr) == 0)) |
| return 0; /* success: the CPU is halted */ |
| |
| /* Otherwise, wait and retry: */ |
| msleep(1); |
| } |
| |
| return -ETIMEDOUT; /* timeout */ |
| } |
| |
| static void exynos_cpu_is_up(unsigned int cpu, unsigned int cluster) |
| { |
| /* especially when resuming: make sure power control is set */ |
| exynos_cpu_powerup(cpu, cluster); |
| } |
| |
| static const struct mcpm_platform_ops exynos_power_ops = { |
| .cpu_powerup = exynos_cpu_powerup, |
| .cluster_powerup = exynos_cluster_powerup, |
| .cpu_powerdown_prepare = exynos_cpu_powerdown_prepare, |
| .cluster_powerdown_prepare = exynos_cluster_powerdown_prepare, |
| .cpu_cache_disable = exynos_cpu_cache_disable, |
| .cluster_cache_disable = exynos_cluster_cache_disable, |
| .wait_for_powerdown = exynos_wait_for_powerdown, |
| .cpu_is_up = exynos_cpu_is_up, |
| }; |
| |
| /* |
| * Enable cluster-level coherency, in preparation for turning on the MMU. |
| */ |
| static void __naked exynos_pm_power_up_setup(unsigned int affinity_level) |
| { |
| asm volatile ("\n" |
| "cmp r0, #1\n" |
| "bxne lr\n" |
| "b cci_enable_port_for_self"); |
| } |
| |
| static const struct of_device_id exynos_dt_mcpm_match[] = { |
| { .compatible = "samsung,exynos5420" }, |
| { .compatible = "samsung,exynos5800" }, |
| {}, |
| }; |
| |
| static void exynos_mcpm_setup_entry_point(void) |
| { |
| /* |
| * U-Boot SPL is hardcoded to jump to the start of ns_sram_base_addr |
| * as part of secondary_cpu_start(). Let's redirect it to the |
| * mcpm_entry_point(). This is done during both secondary boot-up as |
| * well as system resume. |
| */ |
| __raw_writel(0xe59f0000, ns_sram_base_addr); /* ldr r0, [pc, #0] */ |
| __raw_writel(0xe12fff10, ns_sram_base_addr + 4); /* bx r0 */ |
| __raw_writel(virt_to_phys(mcpm_entry_point), ns_sram_base_addr + 8); |
| } |
| |
| static struct syscore_ops exynos_mcpm_syscore_ops = { |
| .resume = exynos_mcpm_setup_entry_point, |
| }; |
| |
| static int __init exynos_mcpm_init(void) |
| { |
| struct device_node *node; |
| unsigned int value, i; |
| int ret; |
| |
| node = of_find_matching_node(NULL, exynos_dt_mcpm_match); |
| if (!node) |
| return -ENODEV; |
| of_node_put(node); |
| |
| if (!cci_probed()) |
| return -ENODEV; |
| |
| node = of_find_compatible_node(NULL, NULL, |
| "samsung,exynos4210-sysram-ns"); |
| if (!node) |
| return -ENODEV; |
| |
| ns_sram_base_addr = of_iomap(node, 0); |
| of_node_put(node); |
| if (!ns_sram_base_addr) { |
| pr_err("failed to map non-secure iRAM base address\n"); |
| return -ENOMEM; |
| } |
| |
| /* |
| * To increase the stability of KFC reset we need to program |
| * the PMU SPARE3 register |
| */ |
| pmu_raw_writel(EXYNOS5420_SWRESET_KFC_SEL, S5P_PMU_SPARE3); |
| |
| ret = mcpm_platform_register(&exynos_power_ops); |
| if (!ret) |
| ret = mcpm_sync_init(exynos_pm_power_up_setup); |
| if (!ret) |
| ret = mcpm_loopback(exynos_cluster_cache_disable); /* turn on the CCI */ |
| if (ret) { |
| iounmap(ns_sram_base_addr); |
| return ret; |
| } |
| |
| mcpm_smp_set_ops(); |
| |
| pr_info("Exynos MCPM support installed\n"); |
| |
| /* |
| * On Exynos5420/5800 for the A15 and A7 clusters: |
| * |
| * EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN ensures that all the cores |
| * in a cluster are turned off before turning off the cluster L2. |
| * |
| * EXYNOS5420_USE_ARM_CORE_DOWN_STATE ensures that a cores is powered |
| * off before waking it up. |
| * |
| * EXYNOS5420_USE_L2_COMMON_UP_STATE ensures that cluster L2 will be |
| * turned on before the first man is powered up. |
| */ |
| for (i = 0; i < EXYNOS5420_NR_CLUSTERS; i++) { |
| value = pmu_raw_readl(EXYNOS_COMMON_OPTION(i)); |
| value |= EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN | |
| EXYNOS5420_USE_ARM_CORE_DOWN_STATE | |
| EXYNOS5420_USE_L2_COMMON_UP_STATE; |
| pmu_raw_writel(value, EXYNOS_COMMON_OPTION(i)); |
| } |
| |
| exynos_mcpm_setup_entry_point(); |
| |
| register_syscore_ops(&exynos_mcpm_syscore_ops); |
| |
| return ret; |
| } |
| |
| early_initcall(exynos_mcpm_init); |