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Diffstat (limited to 'arch/arm64/kernel/psci.c')
-rw-r--r--arch/arm64/kernel/psci.c375
1 files changed, 308 insertions, 67 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
index 14f73c445ff5..fc457d0fee9c 100644
--- a/arch/arm64/kernel/psci.c
+++ b/arch/arm64/kernel/psci.c
@@ -15,97 +15,109 @@
#define pr_fmt(fmt) "psci: " fmt
+#include <linux/cpuidle.h>
#include <linux/init.h>
#include <linux/of.h>
+#include <linux/smp.h>
+#include <linux/slab.h>
+#include <linux/reboot.h>
+#include <linux/pm.h>
+#include <linux/delay.h>
+#include <uapi/linux/psci.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>
-struct psci_operations psci_ops;
+#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 u32 psci_function_id[PSCI_FN_MAX];
+static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state);
-#define PSCI_RET_SUCCESS 0
-#define PSCI_RET_EOPNOTSUPP -1
-#define PSCI_RET_EINVAL -2
-#define PSCI_RET_EPERM -3
+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_EOPNOTSUPP:
+ case PSCI_RET_NOT_SUPPORTED:
return -EOPNOTSUPP;
- case PSCI_RET_EINVAL:
+ case PSCI_RET_INVALID_PARAMS:
return -EINVAL;
- case PSCI_RET_EPERM:
+ case PSCI_RET_DENIED:
return -EPERM;
};
return -EINVAL;
}
-#define PSCI_POWER_STATE_ID_MASK 0xffff
-#define PSCI_POWER_STATE_ID_SHIFT 0
-#define PSCI_POWER_STATE_TYPE_MASK 0x1
-#define PSCI_POWER_STATE_TYPE_SHIFT 16
-#define PSCI_POWER_STATE_AFFL_MASK 0x3
-#define PSCI_POWER_STATE_AFFL_SHIFT 24
-
static u32 psci_power_state_pack(struct psci_power_state state)
{
- return ((state.id & PSCI_POWER_STATE_ID_MASK)
- << PSCI_POWER_STATE_ID_SHIFT) |
- ((state.type & PSCI_POWER_STATE_TYPE_MASK)
- << PSCI_POWER_STATE_TYPE_SHIFT) |
- ((state.affinity_level & PSCI_POWER_STATE_AFFL_MASK)
- << PSCI_POWER_STATE_AFFL_SHIFT);
+ 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);
}
-/*
- * The following two functions are invoked via the invoke_psci_fn pointer
- * and will not be inlined, allowing us to piggyback on the AAPCS.
- */
-static noinline int __invoke_psci_fn_hvc(u64 function_id, u64 arg0, u64 arg1,
- u64 arg2)
+static void psci_power_state_unpack(u32 power_state,
+ struct psci_power_state *state)
{
- asm volatile(
- __asmeq("%0", "x0")
- __asmeq("%1", "x1")
- __asmeq("%2", "x2")
- __asmeq("%3", "x3")
- "hvc #0\n"
- : "+r" (function_id)
- : "r" (arg0), "r" (arg1), "r" (arg2));
-
- return function_id;
+ state->id = (power_state >> PSCI_0_2_POWER_STATE_ID_SHIFT)
+ & PSCI_0_2_POWER_STATE_ID_MASK;
+ state->type = (power_state >> PSCI_0_2_POWER_STATE_TYPE_SHIFT)
+ & PSCI_0_2_POWER_STATE_TYPE_MASK;
+ state->affinity_level = (power_state >> PSCI_0_2_POWER_STATE_AFFL_SHIFT)
+ & PSCI_0_2_POWER_STATE_AFFL_MASK;
}
-static noinline int __invoke_psci_fn_smc(u64 function_id, u64 arg0, u64 arg1,
- u64 arg2)
+static int psci_get_version(void)
{
- asm volatile(
- __asmeq("%0", "x0")
- __asmeq("%1", "x1")
- __asmeq("%2", "x2")
- __asmeq("%3", "x3")
- "smc #0\n"
- : "+r" (function_id)
- : "r" (arg0), "r" (arg1), "r" (arg2));
+ int err;
- return function_id;
+ 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,
@@ -151,28 +163,36 @@ static int psci_migrate(unsigned long cpuid)
return psci_to_linux_errno(err);
}
-static const struct of_device_id psci_of_match[] __initconst = {
- { .compatible = "arm,psci", },
- {},
-};
+static int psci_affinity_info(unsigned long target_affinity,
+ unsigned long lowest_affinity_level)
+{
+ int err;
+ u32 fn;
-int __init psci_init(void)
+ 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)
{
- struct device_node *np;
- const char *method;
- u32 id;
- int err = 0;
+ int err;
+ u32 fn;
- np = of_find_matching_node(NULL, psci_of_match);
- if (!np)
- return -ENODEV;
+ fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
+ err = invoke_psci_fn(fn, 0, 0, 0);
+ return err;
+}
- pr_info("probing function IDs from device-tree\n");
+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_warning("missing \"method\" property\n");
- err = -ENXIO;
- goto out_put_node;
+ pr_warn("missing \"method\" property\n");
+ return -ENXIO;
}
if (!strcmp("hvc", method)) {
@@ -180,11 +200,99 @@ int __init psci_init(void)
} else if (!strcmp("smc", method)) {
invoke_psci_fn = __invoke_psci_fn_smc;
} else {
- pr_warning("invalid \"method\" property: %s\n", method);
- err = -EINVAL;
+ pr_warn("invalid \"method\" property: %s\n", method);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void psci_sys_reset(char str, 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);
+}
+
+/*
+ * PSCI Function IDs for v0.2+ are well defined so use
+ * standard values.
+ */
+static int __init psci_0_2_init(struct device_node *np)
+{
+ int err, ver;
+
+ err = get_set_conduit_method(np);
+
+ if (err)
+ goto out_put_node;
+
+ ver = psci_get_version();
+
+ if (ver == PSCI_RET_NOT_SUPPORTED) {
+ /* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */
+ pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
+ err = -EOPNOTSUPP;
goto out_put_node;
+ } 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) {
+ err = -EINVAL;
+ pr_err("Conflicting PSCI version detected.\n");
+ goto out_put_node;
+ }
}
+ 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;
+
+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;
@@ -209,3 +317,136 @@ 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_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);
+}
+
+#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
+
+#ifdef CONFIG_ARM64_CPU_SUSPEND
+static int cpu_psci_cpu_suspend(unsigned long index)
+{
+ struct psci_power_state *state = __get_cpu_var(psci_power_state);
+
+ if (!state)
+ return -EOPNOTSUPP;
+
+ return psci_ops.cpu_suspend(state[index], virt_to_phys(cpu_resume));
+}
+#endif
+
+const struct cpu_operations cpu_psci_ops = {
+ .name = "psci",
+#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
+#ifdef CONFIG_ARM64_CPU_SUSPEND
+ .cpu_suspend = cpu_psci_cpu_suspend,
+#endif
+};
+