Re: [Linaro-acpi] [PATCH v2 1/3] PSCI: Use DT Function ID values only for old versions of spec

On Thu, Mar 27, 2014 at 10:38 AM, Ashwin Chaugule ashwin.chaugule@linaro.org wrote:

PSCI v0.2+ spec mandates specific values of Function IDs for ARM32 and ARM64. Use DT bindings of Function IDs only when using older versions. Use standard values otherwise.

The subject line is a bit out of date.

Signed-off-by: Ashwin Chaugule ashwin.chaugule@linaro.org

arch/arm/include/asm/psci.h | 7 +- arch/arm/kernel/psci.c | 155 ++++++++++++++++++++++++++++++++++++++++---- arch/arm64/kernel/psci.c | 154 +++++++++++++++++++++++++++++++++++++++---- include/uapi/linux/psci.h | 45 +++++++++++++ 4 files changed, 334 insertions(+), 27 deletions(-) create mode 100644 include/uapi/linux/psci.h

diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h index c4ae171..f867633 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 init 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..77e6968 100644 --- a/arch/arm/kernel/psci.c +++ b/arch/arm/kernel/psci.c @@ -17,6 +17,7 @@

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

#include <asm/compiler.h> #include <asm/errno.h> @@ -27,12 +28,15 @@ 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,
  

};

@@ -110,6 +114,18 @@ static noinline int __invoke_psci_fn_smc(u32 function_id, u32 arg0, u32 arg1, return function_id; }

+#define PSCI_VER_MAJOR_MASK 0xffff0000 +#define PSCI_VER_MINOR_MASK 0x0000ffff +#define PSCI_VER_MAJOR_SHIFT 16

+static int psci_get_version(void) +{

•   int err;
  

•   err = invoke_psci_fn(PSCI_ID_VERSION, 0, 0, 0);
  

•   return err;
  

+}

static int psci_cpu_suspend(struct psci_power_state state, unsigned long entry_point) { @@ -153,25 +169,100 @@ 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) +{

•   int err;
  

•   u32 fn;
  

•   fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
  

•   err = invoke_psci_fn(fn, 0, 0, 0);
  

•   return err;
  

+}

+/*

• • PSCI Function IDs for v0.2+ are well defined so use
• • standard values.
• */

+static int psci_static_init(struct device_node *np) {

•   struct device_node *np;
    const char *method;
  

•   u32 id;
  

•   int err = 0;
  

•   int ver = 0;
  

Initialization not needed.

•   np = of_find_matching_node(NULL, psci_of_match);
  

•   if (!np)
  

•           return;
  

•   pr_info("probing for conduit method from DT.\n");
  

•   if (of_property_read_string(np, "method", &method)) {
  

•           pr_warn("missing \"method\" property\n");
  

•           err = -ENXIO;
  

•           goto out_put_node;
  

•   }
  

•   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);
  

•           err = -EINVAL;
  

•           goto out_put_node;
  

•   }
  

This should all be common setup.

•   ver = psci_get_version();
  

•   pr_info("PSCIv%d.%d detected in firmware.\n",
  

•                   (ver & PSCI_VER_MAJOR_MASK) >> PSCI_VER_MAJOR_SHIFT,
  

•                   (ver & PSCI_VER_MINOR_MASK));
  

If it doesn't report 0.2, then we should probably bail (possibly falling back to 0.1).

•   pr_info("Using standard PSCI v0.2 function IDs\n");
  

•   psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_ID_CPU_SUSPEND;
  

•   psci_ops.cpu_suspend = psci_cpu_suspend;
  

•   psci_function_id[PSCI_FN_CPU_OFF] = PSCI_ID_CPU_OFF;
  

•   psci_ops.cpu_off = psci_cpu_off;
  

•   psci_function_id[PSCI_FN_CPU_ON] = PSCI_ID_CPU_ON;
  

•   psci_ops.cpu_on = psci_cpu_on;
  

•   psci_function_id[PSCI_FN_MIGRATE] = PSCI_ID_CPU_MIGRATE;
  

•   psci_ops.migrate = psci_migrate;
  

•   psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_ID_AFFINITY_INFO;
  

•   psci_ops.affinity_info = psci_affinity_info;
  

•   psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] = PSCI_ID_MIGRATE_INFO_TYPE;
  

•   psci_ops.migrate_info_type = psci_migrate_info_type;
  

+out_put_node:

•   of_node_put(np);
  

•   return err;
  

+}

+/*

• • PSCI < v0.2 can override PSCI function IDs via DT.
• */

+static int psci_of_init(struct device_node *np) +{

•   const char *method;
  

•   u32 id;
  

•   int err = 0;
  

•   int ver = 0;
  
    pr_info("probing function IDs from device-tree\n");
  
    if (of_property_read_string(np, "method", &method)) {
  

•           pr_warning("missing \"method\" property\n");
  

•           pr_warn("missing \"method\" property\n");
  

•           err = -EINVAL;
            goto out_put_node;
    }
  
  

@@ -180,10 +271,17 @@ 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);
  

•           err = -ENXIO;
            goto out_put_node;
    }
  
  

•   ver = psci_get_version();
  

This may not be safe to do on 0.1 as the call didn't exist.

•   pr_info("PSCIv%d.%d detected in firmware.\n",
  

•                   (ver & PSCI_VER_MAJOR_MASK) >> PSCI_VER_MAJOR_SHIFT,
  

•                   (ver & PSCI_VER_MINOR_MASK));
  

•   if (!of_property_read_u32(np, "cpu_suspend", &id)) {
            psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
            psci_ops.cpu_suspend = psci_cpu_suspend;
  

@@ -204,7 +302,38 @@ void __init psci_init(void) psci_ops.migrate = psci_migrate; }

•   if (!of_property_read_u32(np, "affinity_info", &id)) {
  

•           psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_ID_AFFINITY_INFO;
  

•           psci_ops.affinity_info = psci_affinity_info;
  

•   }
  

•   if (!of_property_read_u32(np, "migrate_info_type", &id)) {
  

•           psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE]
  

•                   = PSCI_ID_MIGRATE_INFO_TYPE;
  

•           psci_ops.migrate_info_type = psci_migrate_info_type;
  

•   }
  

These 2 functions don't exist for 0.1.

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_of_init},
  

•   { .compatible = "arm,psci-0.2", .data = psci_static_init},
  

"of" and "static" don't really describe the difference here. Use something like psci_init_0_1 and psci_init_0_2.

•   {},
  

+};

+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/kernel/psci.c b/arch/arm64/kernel/psci.c index 4f97db3..61b7871 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c

Same comments apply to this file.

@@ -18,6 +18,7 @@ #include <linux/init.h> #include <linux/of.h> #include <linux/smp.h> +#include <uapi/linux/psci.h>

#include <asm/compiler.h> #include <asm/cpu_ops.h> @@ -40,17 +41,23 @@ 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,
  

};

@@ -128,6 +135,18 @@ static noinline int __invoke_psci_fn_smc(u64 function_id, u64 arg0, u64 arg1, return function_id; }

+#define PSCI_VER_MAJOR_MASK 0xffff0000 +#define PSCI_VER_MINOR_MASK 0x0000ffff +#define PSCI_VER_MAJOR_SHIFT 16

+static int psci_get_version(void) +{

•   int err;
  

•   err = invoke_psci_fn(PSCI_ID_VERSION, 0, 0, 0);
  

•   return err;
  

+}

static int psci_cpu_suspend(struct psci_power_state state, unsigned long entry_point) { @@ -171,26 +190,99 @@ 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) +{

•   int err;
  

•   u32 fn;
  

•   fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
  

•   err = invoke_psci_fn(fn, 0, 0, 0);
  

•   return err;
  

+}

+/*

• • PSCI Function IDs for v0.2+ are well defined so use
• • standard values.
• */

+static int psci_static_init(struct device_node *np) {

•   struct device_node *np;
    const char *method;
  

•   u32 id;
    int err = 0;
  

•   int ver = 0;
  
  

•   np = of_find_matching_node(NULL, psci_of_match);
  

•   if (!np)
  

•           return -ENODEV;
  

•   pr_info("probing for conduit method from DT.\n");
  

•   if (of_property_read_string(np, "method", &method)) {
  

•           pr_warn("missing \"method\" property\n");
  

•           err = -ENXIO;
  

•           goto out_put_node;
  

•   }
  

•   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);
  

•           err = -EINVAL;
  

•           goto out_put_node;
  

•   }
  

•   ver = psci_get_version();
  

•   pr_info("PSCIv%d.%d detected in firmware.\n",
  

•                   (ver & PSCI_VER_MAJOR_MASK) >> PSCI_VER_MAJOR_SHIFT,
  

•                   (ver & PSCI_VER_MINOR_MASK));
  

•   pr_info("Using standard PSCI v0.2 function IDs\n");
  

•   psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_ID_CPU_SUSPEND;
  

•   psci_ops.cpu_suspend = psci_cpu_suspend;
  

•   psci_function_id[PSCI_FN_CPU_OFF] = PSCI_ID_CPU_OFF;
  

•   psci_ops.cpu_off = psci_cpu_off;
  

•   psci_function_id[PSCI_FN_CPU_ON] = PSCI_ID_CPU_ON;
  

•   psci_ops.cpu_on = psci_cpu_on;
  

•   psci_function_id[PSCI_FN_MIGRATE] = PSCI_ID_CPU_MIGRATE;
  

•   psci_ops.migrate = psci_migrate;
  

•   psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_ID_AFFINITY_INFO;
  

•   psci_ops.affinity_info = psci_affinity_info;
  

•   psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] = PSCI_ID_MIGRATE_INFO_TYPE;
  

•   psci_ops.migrate_info_type = psci_migrate_info_type;
  

+out_put_node:

•   of_node_put(np);
  

•   return err;
  

+}

+/*

• • PSCI < v0.2 can override PSCI function IDs via DT.
• */

+static int psci_of_init(struct device_node *np) +{

•   const char *method;
  

•   u32 id;
  

•   int err = 0;
  

•   int ver = 0;
  
    pr_info("probing function IDs from device-tree\n");
  
    if (of_property_read_string(np, "method", &method)) {
  

•           pr_warning("missing \"method\" property\n");
  

•           pr_warn("missing \"method\" property\n");
            err = -ENXIO;
            goto out_put_node;
    }
  

@@ -200,11 +292,17 @@ 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);
  

•           pr_warn("invalid \"method\" property: %s\n", method);
            err = -EINVAL;
            goto out_put_node;
    }
  
  

•   ver = psci_get_version();
  

•   pr_info("PSCIv%d.%d detected in firmware.\n",
  

•                   (ver & PSCI_VER_MAJOR_MASK) >> PSCI_VER_MAJOR_SHIFT,
  

•                   (ver & PSCI_VER_MINOR_MASK));
  

•   if (!of_property_read_u32(np, "cpu_suspend", &id)) {
            psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
            psci_ops.cpu_suspend = psci_cpu_suspend;
  

@@ -225,11 +323,43 @@ int __init psci_init(void) psci_ops.migrate = psci_migrate; }

•   if (!of_property_read_u32(np, "affinity_info", &id)) {
  

•           psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_ID_AFFINITY_INFO;
  

•           psci_ops.affinity_info = psci_affinity_info;
  

•   }
  

•   if (!of_property_read_u32(np, "migrate_info_type", &id)) {
  

•           psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE]
  

•                   = PSCI_ID_MIGRATE_INFO_TYPE;
  

•           psci_ops.migrate_info_type = psci_migrate_info_type;
  

•   }
  

out_put_node: of_node_put(np); return err; }

+static const struct of_device_id psci_of_match[] __initconst = {

•   { .compatible = "arm,psci",     .data = psci_of_init},
  

•   { .compatible = "arm,psci-0.2", .data = psci_static_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) diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h new file mode 100644 index 0000000..b271e9a --- /dev/null +++ b/include/uapi/linux/psci.h @@ -0,0 +1,45 @@ +/*

Linaro copyright?

• • This program is free software; you can redistribute it and/or modify
• • it under the terms of the GNU General Public License as published by
• • the Free Software Foundation; either version 2 of the License, or
• • (at your option) any later version.
• • 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.
• */

+#ifndef _UAPI_LINUX_PSCI_H +#define _UAPI_LINUX_PSCI_H

+/* PSCI Function IDs for ARM32 as per PSCI spec v0.2 */ +#ifdef CONFIG_ARM_PSCI +#define PSCI_ID_VERSION 0x84000000 +#define PSCI_ID_CPU_SUSPEND 0x84000001 +#define PSCI_ID_CPU_OFF 0x84000002 +#define PSCI_ID_CPU_ON 0x84000003 +#define PSCI_ID_AFFINITY_INFO 0x84000004 +#define PSCI_ID_CPU_MIGRATE 0x84000005 +#define PSCI_ID_MIGRATE_INFO_TYPE 0x84000006 +#define PSCI_ID_MIGRATE_INFO_UP_CPU 0x84000007 +#define PSCI_ID_SYSTEM_OFF 0x84000008 +#define PSCI_ID_SYSTEM_RESET 0x84000009 +#endif

+/* PSCI Function IDs for ARM64 as per PSCI spec v0.2 */ +#ifdef CONFIG_ARM64

You don't need ifdefs here. The 32-bit calls are valid on arm64 as that is what 32-bit guests will use. Just do something like this:

#define PSCI_ID_VERSION 0x84000000 #define PSCI_ID_CPU_SUSPEND_32 0x84000001 #define PSCI_ID_CPU_SUSPEND_64 0xc4000001

+#define PSCI_ID_VERSION 0x84000000 +#define PSCI_ID_CPU_SUSPEND 0xc4000001 +#define PSCI_ID_CPU_OFF 0x84000002 +#define PSCI_ID_CPU_ON 0xc4000003 +#define PSCI_ID_AFFINITY_INFO 0xc4000004 +#define PSCI_ID_CPU_MIGRATE 0xc4000005 +#define PSCI_ID_MIGRATE_INFO_TYPE 0x84000006 +#define PSCI_ID_MIGRATE_INFO_UP_CPU 0xc4000007 +#define PSCI_ID_SYSTEM_OFF 0x84000008 +#define PSCI_ID_SYSTEM_RESET 0x84000009 +#endif

+#endif /* _UAPI_LINUX_PSCI_H */

1.8.3.2