[PATCH 13/16] PSCI: Add initial support for PSCIv0.2 functions

Christoffer Dall
2014-05-25T18:19:39Z

From: Ashwin Chaugule <ashwin.chaugule@linaro.org>

The PSCIv0.2 spec defines standard values of function IDs
and introduces a few new functions. Detect version of PSCI
and appropriately select the right PSCI functions.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
---
arch/arm/include/asm/psci.h | 7 +-
arch/arm/kernel/psci.c | 196 +++++++++++++++++++++++++++++++++--------
arch/arm64/include/asm/psci.h | 2 +-
arch/arm64/kernel/psci.c | 200 ++++++++++++++++++++++++++++++++++--------
4 files changed, 328 insertions(+), 77 deletions(-)

diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h
index c4ae171..b93e34a 100644
--- a/arch/arm/include/asm/psci.h
+++ b/arch/arm/include/asm/psci.h
@@ -29,16 +29,19 @@ struct psci_operations {
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);
};

extern struct psci_operations psci_ops;
extern struct smp_operations psci_smp_ops;

#ifdef CONFIG_ARM_PSCI
-void psci_init(void);
+int psci_init(void);
bool psci_smp_available(void);
#else
-static inline void psci_init(void) { }
+static inline int psci_init(void) { }
static inline bool psci_smp_available(void) { return false; }
#endif

diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c
index 4693188..f73891b 100644
--- a/arch/arm/kernel/psci.c
+++ b/arch/arm/kernel/psci.c
@@ -17,63 +17,58 @@

#include <linux/init.h>
#include <linux/of.h>
+#include <linux/reboot.h>
+#include <linux/pm.h>
+#include <uapi/linux/psci.h>

#include <asm/compiler.h>
#include <asm/errno.h>
#include <asm/opcodes-sec.h>
#include <asm/opcodes-virt.h>
#include <asm/psci.h>
+#include <asm/system_misc.h>

struct psci_operations psci_ops;

static int (*invoke_psci_fn)(u32, u32, u32, u32);
+typedef int (*psci_initcall_t)(const struct device_node *);

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];

-#define PSCI_RET_SUCCESS 0
-#define PSCI_RET_EOPNOTSUPP -1
-#define PSCI_RET_EINVAL -2
-#define PSCI_RET_EPERM -3
-
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);
}

/*
@@ -110,6 +105,14 @@ static noinline int __invoke_psci_fn_smc(u32 function_id, u32 arg0, u32 arg1,
return function_id;
}

+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)
{
@@ -153,26 +156,36 @@ 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;
+
+ fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
+ err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
+ return err;
+}

-void __init psci_init(void)
+static int psci_migrate_info_type(void)
{
- struct device_node *np;
- const char *method;
- u32 id;
+ int err;
+ u32 fn;

- np = of_find_matching_node(NULL, psci_of_match);
- if (!np)
- return;
+ fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
+ err = invoke_psci_fn(fn, 0, 0, 0);
+ return err;
+}
+
+static int get_set_conduit_method(struct device_node *np)
+{
+ const char *method;

- pr_info("probing function IDs from device-tree\n");
+ pr_info("probing for conduit method from DT.\n");

if (of_property_read_string(np, "method", &method)) {
- pr_warning("missing \"method\" property\n");
- goto out_put_node;
+ pr_warn("missing \"method\" property\n");
+ return -ENXIO;
}

if (!strcmp("hvc", method)) {
@@ -180,10 +193,99 @@ void __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);
+ 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);
+}
+
+/*
+ * PSCI Function IDs for v0.2+ are well defined so use
+ * standard values.
+ */
+static int 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_FN_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_FN_CPU_ON;
+ psci_ops.cpu_on = psci_cpu_on;
+
+ psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_MIGRATE;
+ psci_ops.migrate = psci_migrate;
+
+ psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN_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 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;
@@ -206,5 +308,25 @@ void __init psci_init(void)

out_put_node:
of_node_put(np);
- return;
+ 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);
}
diff --git a/arch/arm64/include/asm/psci.h b/arch/arm64/include/asm/psci.h
index d15ab8b4..e5312ea 100644
--- a/arch/arm64/include/asm/psci.h
+++ b/arch/arm64/include/asm/psci.h
@@ -14,6 +14,6 @@
#ifndef __ASM_PSCI_H
#define __ASM_PSCI_H

-void psci_init(void);
+int psci_init(void);

#endif /* __ASM_PSCI_H */
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
index ea4828a..90df6e6 100644
--- a/arch/arm64/kernel/psci.c
+++ b/arch/arm64/kernel/psci.c
@@ -18,12 +18,16 @@
#include <linux/init.h>
#include <linux/of.h>
#include <linux/smp.h>
+#include <linux/reboot.h>
+#include <linux/pm.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/system_misc.h>

#define PSCI_POWER_STATE_TYPE_STANDBY 0
#define PSCI_POWER_STATE_TYPE_POWER_DOWN 1
@@ -40,58 +44,52 @@ struct psci_operations {
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 *);

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];

-#define PSCI_RET_SUCCESS 0
-#define PSCI_RET_EOPNOTSUPP -1
-#define PSCI_RET_EINVAL -2
-#define PSCI_RET_EPERM -3
-
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);
}

/*
@@ -128,6 +126,14 @@ static noinline int __invoke_psci_fn_smc(u64 function_id, u64 arg0, u64 arg1,
return function_id;
}

+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)
{
@@ -171,26 +177,36 @@ 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;
+
+ fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
+ err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
+ return err;
+}

-void __init psci_init(void)
+static int psci_migrate_info_type(void)
{
- struct device_node *np;
- const char *method;
- u32 id;
+ int err;
+ u32 fn;

- np = of_find_matching_node(NULL, psci_of_match);
- if (!np)
- return;
+ fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
+ err = invoke_psci_fn(fn, 0, 0, 0);
+ return err;
+}
+
+static int get_set_conduit_method(struct device_node *np)
+{
+ const char *method;

- pr_info("probing function IDs from device-tree\n");
+ pr_info("probing for conduit method from DT.\n");

if (of_property_read_string(np, "method", &method)) {
- pr_warning("missing \"method\" property\n");
- goto out_put_node;
+ pr_warn("missing \"method\" property\n");
+ return -ENXIO;
}

if (!strcmp("hvc", method)) {
@@ -198,10 +214,99 @@ void __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);
+ 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);
+}
+
+/*
+ * PSCI Function IDs for v0.2+ are well defined so use
+ * standard values.
+ */
+static int 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 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;
@@ -224,7 +329,28 @@ void __init psci_init(void)

out_put_node:
of_node_put(np);
- return;
+ 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
--
1.8.5.2