--- /dev/null
+/*
+ * 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 "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;
+
+ exynos_cpu_power_up(cpunr);
+ 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);
Code Review / kvmfornfv.git / blobdiff