Commit e71246a2 authored by Ashwin Chaugule's avatar Ashwin Chaugule
Browse files

PSCI: Add initial support for PSCIv0.2 functions 



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: default avatarAshwin Chaugule <ashwin.chaugule@linaro.org>
Reviewed-by: default avatarRob Herring <robh@kernel.org>
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 4447a208

arch/arm/include/asm/psci.h

+5 −2
Original line number Diff line number Diff line
@@ -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

arch/arm/kernel/psci.c

+159 −37
Original line number Diff line number Diff line
@@ -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;

}



	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");

		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);

}

arch/arm64/include/asm/psci.h

+1 −1
Original line number Diff line number Diff line
@@ -14,6 +14,6 @@ 
#ifndef __ASM_PSCI_H

#define __ASM_PSCI_H



void psci_init(void);

int psci_init(void);



#endif /* __ASM_PSCI_H */

arch/arm64/kernel/psci.c

+163 −37
Original line number Diff line number Diff line
@@ -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)) {
@@ -198,9 +214,98 @@ 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;
@@ -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

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