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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/arm64/kernel/psci.c
Initial import
Diffstat (limited to 'arch/arm64/kernel/psci.c')
-rw-r--r--arch/arm64/kernel/psci.c571
1 files changed, 571 insertions, 0 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
new file mode 100644
index 000000000..ea18cb539
--- /dev/null
+++ b/arch/arm64/kernel/psci.c
@@ -0,0 +1,571 @@
+/*
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2013 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ */
+
+#define pr_fmt(fmt) "psci: " fmt
+
+#include <linux/acpi.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/smp.h>
+#include <linux/reboot.h>
+#include <linux/pm.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <uapi/linux/psci.h>
+
+#include <asm/acpi.h>
+#include <asm/compiler.h>
+#include <asm/cpu_ops.h>
+#include <asm/errno.h>
+#include <asm/psci.h>
+#include <asm/smp_plat.h>
+#include <asm/suspend.h>
+#include <asm/system_misc.h>
+
+#define PSCI_POWER_STATE_TYPE_STANDBY 0
+#define PSCI_POWER_STATE_TYPE_POWER_DOWN 1
+
+struct psci_power_state {
+ u16 id;
+ u8 type;
+ u8 affinity_level;
+};
+
+struct psci_operations {
+ int (*cpu_suspend)(struct psci_power_state state,
+ unsigned long entry_point);
+ int (*cpu_off)(struct psci_power_state state);
+ int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
+ int (*migrate)(unsigned long cpuid);
+ int (*affinity_info)(unsigned long target_affinity,
+ unsigned long lowest_affinity_level);
+ int (*migrate_info_type)(void);
+};
+
+static struct psci_operations psci_ops;
+
+static int (*invoke_psci_fn)(u64, u64, u64, u64);
+typedef int (*psci_initcall_t)(const struct device_node *);
+
+asmlinkage int __invoke_psci_fn_hvc(u64, u64, u64, u64);
+asmlinkage int __invoke_psci_fn_smc(u64, u64, u64, u64);
+
+enum psci_function {
+ PSCI_FN_CPU_SUSPEND,
+ PSCI_FN_CPU_ON,
+ PSCI_FN_CPU_OFF,
+ PSCI_FN_MIGRATE,
+ PSCI_FN_AFFINITY_INFO,
+ PSCI_FN_MIGRATE_INFO_TYPE,
+ PSCI_FN_MAX,
+};
+
+static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state);
+
+static u32 psci_function_id[PSCI_FN_MAX];
+
+static int psci_to_linux_errno(int errno)
+{
+ switch (errno) {
+ case PSCI_RET_SUCCESS:
+ return 0;
+ case PSCI_RET_NOT_SUPPORTED:
+ return -EOPNOTSUPP;
+ case PSCI_RET_INVALID_PARAMS:
+ return -EINVAL;
+ case PSCI_RET_DENIED:
+ return -EPERM;
+ };
+
+ return -EINVAL;
+}
+
+static u32 psci_power_state_pack(struct psci_power_state state)
+{
+ return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT)
+ & PSCI_0_2_POWER_STATE_ID_MASK) |
+ ((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT)
+ & PSCI_0_2_POWER_STATE_TYPE_MASK) |
+ ((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
+ & PSCI_0_2_POWER_STATE_AFFL_MASK);
+}
+
+static void psci_power_state_unpack(u32 power_state,
+ struct psci_power_state *state)
+{
+ state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >>
+ PSCI_0_2_POWER_STATE_ID_SHIFT;
+ state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >>
+ PSCI_0_2_POWER_STATE_TYPE_SHIFT;
+ state->affinity_level =
+ (power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >>
+ PSCI_0_2_POWER_STATE_AFFL_SHIFT;
+}
+
+static int psci_get_version(void)
+{
+ int err;
+
+ err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
+ return err;
+}
+
+static int psci_cpu_suspend(struct psci_power_state state,
+ unsigned long entry_point)
+{
+ int err;
+ u32 fn, power_state;
+
+ fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
+ power_state = psci_power_state_pack(state);
+ err = invoke_psci_fn(fn, power_state, entry_point, 0);
+ return psci_to_linux_errno(err);
+}
+
+static int psci_cpu_off(struct psci_power_state state)
+{
+ int err;
+ u32 fn, power_state;
+
+ fn = psci_function_id[PSCI_FN_CPU_OFF];
+ power_state = psci_power_state_pack(state);
+ err = invoke_psci_fn(fn, power_state, 0, 0);
+ return psci_to_linux_errno(err);
+}
+
+static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
+{
+ int err;
+ u32 fn;
+
+ fn = psci_function_id[PSCI_FN_CPU_ON];
+ err = invoke_psci_fn(fn, cpuid, entry_point, 0);
+ return psci_to_linux_errno(err);
+}
+
+static int psci_migrate(unsigned long cpuid)
+{
+ int err;
+ u32 fn;
+
+ fn = psci_function_id[PSCI_FN_MIGRATE];
+ err = invoke_psci_fn(fn, cpuid, 0, 0);
+ return psci_to_linux_errno(err);
+}
+
+static int psci_affinity_info(unsigned long target_affinity,
+ unsigned long lowest_affinity_level)
+{
+ int err;
+ u32 fn;
+
+ fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
+ err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
+ return err;
+}
+
+static int psci_migrate_info_type(void)
+{
+ int err;
+ u32 fn;
+
+ fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
+ err = invoke_psci_fn(fn, 0, 0, 0);
+ return err;
+}
+
+static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node,
+ unsigned int cpu)
+{
+ int i, ret, count = 0;
+ struct psci_power_state *psci_states;
+ struct device_node *state_node;
+
+ /*
+ * If the PSCI cpu_suspend function hook has not been initialized
+ * idle states must not be enabled, so bail out
+ */
+ if (!psci_ops.cpu_suspend)
+ return -EOPNOTSUPP;
+
+ /* Count idle states */
+ while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
+ count))) {
+ count++;
+ of_node_put(state_node);
+ }
+
+ if (!count)
+ return -ENODEV;
+
+ psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
+ if (!psci_states)
+ return -ENOMEM;
+
+ for (i = 0; i < count; i++) {
+ u32 psci_power_state;
+
+ state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
+
+ ret = of_property_read_u32(state_node,
+ "arm,psci-suspend-param",
+ &psci_power_state);
+ if (ret) {
+ pr_warn(" * %s missing arm,psci-suspend-param property\n",
+ state_node->full_name);
+ of_node_put(state_node);
+ goto free_mem;
+ }
+
+ of_node_put(state_node);
+ pr_debug("psci-power-state %#x index %d\n", psci_power_state,
+ i);
+ psci_power_state_unpack(psci_power_state, &psci_states[i]);
+ }
+ /* Idle states parsed correctly, initialize per-cpu pointer */
+ per_cpu(psci_power_state, cpu) = psci_states;
+ return 0;
+
+free_mem:
+ kfree(psci_states);
+ return ret;
+}
+
+static int get_set_conduit_method(struct device_node *np)
+{
+ const char *method;
+
+ pr_info("probing for conduit method from DT.\n");
+
+ if (of_property_read_string(np, "method", &method)) {
+ pr_warn("missing \"method\" property\n");
+ return -ENXIO;
+ }
+
+ if (!strcmp("hvc", method)) {
+ invoke_psci_fn = __invoke_psci_fn_hvc;
+ } else if (!strcmp("smc", method)) {
+ invoke_psci_fn = __invoke_psci_fn_smc;
+ } else {
+ pr_warn("invalid \"method\" property: %s\n", method);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
+{
+ invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
+}
+
+static void psci_sys_poweroff(void)
+{
+ invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
+}
+
+static void __init psci_0_2_set_functions(void)
+{
+ pr_info("Using standard PSCI v0.2 function IDs\n");
+ psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND;
+ psci_ops.cpu_suspend = psci_cpu_suspend;
+
+ psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
+ psci_ops.cpu_off = psci_cpu_off;
+
+ psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN64_CPU_ON;
+ psci_ops.cpu_on = psci_cpu_on;
+
+ psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE;
+ psci_ops.migrate = psci_migrate;
+
+ psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN64_AFFINITY_INFO;
+ psci_ops.affinity_info = psci_affinity_info;
+
+ psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] =
+ PSCI_0_2_FN_MIGRATE_INFO_TYPE;
+ psci_ops.migrate_info_type = psci_migrate_info_type;
+
+ arm_pm_restart = psci_sys_reset;
+
+ pm_power_off = psci_sys_poweroff;
+}
+
+/*
+ * Probe function for PSCI firmware versions >= 0.2
+ */
+static int __init psci_probe(void)
+{
+ int ver = psci_get_version();
+
+ if (ver == PSCI_RET_NOT_SUPPORTED) {
+ /*
+ * PSCI versions >=0.2 mandates implementation of
+ * PSCI_VERSION.
+ */
+ pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
+ return -EOPNOTSUPP;
+ } else {
+ pr_info("PSCIv%d.%d detected in firmware.\n",
+ PSCI_VERSION_MAJOR(ver),
+ PSCI_VERSION_MINOR(ver));
+
+ if (PSCI_VERSION_MAJOR(ver) == 0 &&
+ PSCI_VERSION_MINOR(ver) < 2) {
+ pr_err("Conflicting PSCI version detected.\n");
+ return -EINVAL;
+ }
+ }
+
+ psci_0_2_set_functions();
+
+ return 0;
+}
+
+/*
+ * PSCI init function for PSCI versions >=0.2
+ *
+ * Probe based on PSCI PSCI_VERSION function
+ */
+static int __init psci_0_2_init(struct device_node *np)
+{
+ int err;
+
+ err = get_set_conduit_method(np);
+
+ if (err)
+ goto out_put_node;
+ /*
+ * Starting with v0.2, the PSCI specification introduced a call
+ * (PSCI_VERSION) that allows probing the firmware version, so
+ * that PSCI function IDs and version specific initialization
+ * can be carried out according to the specific version reported
+ * by firmware
+ */
+ err = psci_probe();
+
+out_put_node:
+ of_node_put(np);
+ return err;
+}
+
+/*
+ * PSCI < v0.2 get PSCI Function IDs via DT.
+ */
+static int __init psci_0_1_init(struct device_node *np)
+{
+ u32 id;
+ int err;
+
+ err = get_set_conduit_method(np);
+
+ if (err)
+ goto out_put_node;
+
+ pr_info("Using PSCI v0.1 Function IDs from DT\n");
+
+ if (!of_property_read_u32(np, "cpu_suspend", &id)) {
+ psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
+ psci_ops.cpu_suspend = psci_cpu_suspend;
+ }
+
+ if (!of_property_read_u32(np, "cpu_off", &id)) {
+ psci_function_id[PSCI_FN_CPU_OFF] = id;
+ psci_ops.cpu_off = psci_cpu_off;
+ }
+
+ if (!of_property_read_u32(np, "cpu_on", &id)) {
+ psci_function_id[PSCI_FN_CPU_ON] = id;
+ psci_ops.cpu_on = psci_cpu_on;
+ }
+
+ if (!of_property_read_u32(np, "migrate", &id)) {
+ psci_function_id[PSCI_FN_MIGRATE] = id;
+ psci_ops.migrate = psci_migrate;
+ }
+
+out_put_node:
+ of_node_put(np);
+ return err;
+}
+
+static const struct of_device_id psci_of_match[] __initconst = {
+ { .compatible = "arm,psci", .data = psci_0_1_init},
+ { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
+ {},
+};
+
+int __init psci_dt_init(void)
+{
+ struct device_node *np;
+ const struct of_device_id *matched_np;
+ psci_initcall_t init_fn;
+
+ np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
+
+ if (!np)
+ return -ENODEV;
+
+ init_fn = (psci_initcall_t)matched_np->data;
+ return init_fn(np);
+}
+
+/*
+ * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
+ * explicitly clarified in SBBR
+ */
+int __init psci_acpi_init(void)
+{
+ if (!acpi_psci_present()) {
+ pr_info("is not implemented in ACPI.\n");
+ return -EOPNOTSUPP;
+ }
+
+ pr_info("probing for conduit method from ACPI.\n");
+
+ if (acpi_psci_use_hvc())
+ invoke_psci_fn = __invoke_psci_fn_hvc;
+ else
+ invoke_psci_fn = __invoke_psci_fn_smc;
+
+ return psci_probe();
+}
+
+#ifdef CONFIG_SMP
+
+static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu)
+{
+ return 0;
+}
+
+static int __init cpu_psci_cpu_prepare(unsigned int cpu)
+{
+ if (!psci_ops.cpu_on) {
+ pr_err("no cpu_on method, not booting CPU%d\n", cpu);
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int cpu_psci_cpu_boot(unsigned int cpu)
+{
+ int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry));
+ if (err)
+ pr_err("failed to boot CPU%d (%d)\n", cpu, err);
+
+ return err;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int cpu_psci_cpu_disable(unsigned int cpu)
+{
+ /* Fail early if we don't have CPU_OFF support */
+ if (!psci_ops.cpu_off)
+ return -EOPNOTSUPP;
+ return 0;
+}
+
+static void cpu_psci_cpu_die(unsigned int cpu)
+{
+ int ret;
+ /*
+ * There are no known implementations of PSCI actually using the
+ * power state field, pass a sensible default for now.
+ */
+ struct psci_power_state state = {
+ .type = PSCI_POWER_STATE_TYPE_POWER_DOWN,
+ };
+
+ ret = psci_ops.cpu_off(state);
+
+ pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
+}
+
+static int cpu_psci_cpu_kill(unsigned int cpu)
+{
+ int err, i;
+
+ if (!psci_ops.affinity_info)
+ return 1;
+ /*
+ * cpu_kill could race with cpu_die and we can
+ * potentially end up declaring this cpu undead
+ * while it is dying. So, try again a few times.
+ */
+
+ for (i = 0; i < 10; i++) {
+ err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
+ if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
+ pr_info("CPU%d killed.\n", cpu);
+ return 1;
+ }
+
+ msleep(10);
+ pr_info("Retrying again to check for CPU kill\n");
+ }
+
+ pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
+ cpu, err);
+ /* Make op_cpu_kill() fail. */
+ return 0;
+}
+#endif
+#endif
+
+static int psci_suspend_finisher(unsigned long index)
+{
+ struct psci_power_state *state = __this_cpu_read(psci_power_state);
+
+ return psci_ops.cpu_suspend(state[index - 1],
+ virt_to_phys(cpu_resume));
+}
+
+static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
+{
+ int ret;
+ struct psci_power_state *state = __this_cpu_read(psci_power_state);
+ /*
+ * idle state index 0 corresponds to wfi, should never be called
+ * from the cpu_suspend operations
+ */
+ if (WARN_ON_ONCE(!index))
+ return -EINVAL;
+
+ if (state[index - 1].type == PSCI_POWER_STATE_TYPE_STANDBY)
+ ret = psci_ops.cpu_suspend(state[index - 1], 0);
+ else
+ ret = __cpu_suspend(index, psci_suspend_finisher);
+
+ return ret;
+}
+
+const struct cpu_operations cpu_psci_ops = {
+ .name = "psci",
+#ifdef CONFIG_CPU_IDLE
+ .cpu_init_idle = cpu_psci_cpu_init_idle,
+ .cpu_suspend = cpu_psci_cpu_suspend,
+#endif
+#ifdef CONFIG_SMP
+ .cpu_init = cpu_psci_cpu_init,
+ .cpu_prepare = cpu_psci_cpu_prepare,
+ .cpu_boot = cpu_psci_cpu_boot,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_disable = cpu_psci_cpu_disable,
+ .cpu_die = cpu_psci_cpu_die,
+ .cpu_kill = cpu_psci_cpu_kill,
+#endif
+#endif
+};
+