[PATCH v1 1/2] PSCI: Use DT Function ID values only for old versions of spec
Christoffer Dall
christoffer.dall at linaro.org
Wed Mar 19 23:06:14 EDT 2014
On Wed, Mar 19, 2014 at 08:54:24PM -0400, Ashwin Chaugule wrote:
> The 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 static values otherwise.
> This patch also prepares the code to easily use the ACPI API
> which is based off of PSCI v0.2+.
>
> Signed-off-by: Ashwin Chaugule <ashwin.chaugule at linaro.org>
> ---
> arch/arm/include/asm/psci.h | 15 ++++++
> arch/arm/kernel/psci.c | 110 +++++++++++++++++++++++++++++++++++++-----
> arch/arm64/include/asm/psci.h | 12 +++++
> arch/arm64/kernel/psci.c | 106 +++++++++++++++++++++++++++++++++++-----
> 4 files changed, 218 insertions(+), 25 deletions(-)
>
> diff --git a/arch/arm/include/asm/psci.h b/arch/arm/include/asm/psci.h
> index c4ae171..3f8ebf9 100644
> --- a/arch/arm/include/asm/psci.h
> +++ b/arch/arm/include/asm/psci.h
> @@ -17,6 +17,19 @@
> #define PSCI_POWER_STATE_TYPE_STANDBY 0
> #define PSCI_POWER_STATE_TYPE_POWER_DOWN 1
>
> +/* PSCI Function ID's for ARM32 as per PSCI spec v0.2 */
> +
> +#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
> +
> struct psci_power_state {
> u16 id;
> u8 type;
> @@ -36,9 +49,11 @@ extern struct smp_operations psci_smp_ops;
>
> #ifdef CONFIG_ARM_PSCI
> void psci_init(void);
> +int psci_get_version(void);
> bool psci_smp_available(void);
> #else
> static inline void psci_init(void) { }
> +static inline int psci_get_version(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..48e0b0a 100644
> --- a/arch/arm/kernel/psci.c
> +++ b/arch/arm/kernel/psci.c
> @@ -27,6 +27,7 @@
> 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,
> @@ -110,6 +111,20 @@ 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;
> + u32 fn;
> +
> + fn = PSCI_ID_VERSION;
> + err = invoke_psci_fn(fn, 0, 0, 0);
> + return err;
> +}
> +
> static int psci_cpu_suspend(struct psci_power_state state,
> unsigned long entry_point)
> {
> @@ -153,25 +168,65 @@ 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", },
> - {},
> -};
> +/*
> + * PSCI Function ID's for v0.2+ are well defined so use
> + * static values.
> + */
> +static int psci_static_init(struct device_node *np)
> +{
> + const char *method;
> + int err = 0;
> +
> + 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;
> + }
>
> -void __init psci_init(void)
> + pr_info("Using static PSCIv0.2+ 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;
> +
> +out_put_node:
> + of_node_put(np);
> + return err;
> +}
> +
> +/*
> + * PSCI < v0.2 can override PSCI function ID's via DT.
> + */
> +static int psci_of_init(struct device_node *np)
> {
> - struct device_node *np;
> const char *method;
> u32 id;
> -
> - np = of_find_matching_node(NULL, psci_of_match);
> - if (!np)
> - return;
> + int err = 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;
> }
>
> @@ -180,7 +235,8 @@ 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;
> }
>
> @@ -206,5 +262,33 @@ 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_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;
> + int ver = 0;
> +
> + np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
> + if (!np)
> + return -ENODEV;
> +
> + ver = psci_get_version();
> +
> + pr_info("using static PSCIv%d.%d Function IDs\n",
> + (ver & PSCI_VER_MAJOR_MASK) >> PSCI_VER_MAJOR_SHIFT,
> + (ver & PSCI_VER_MINOR_MASK));
> +
> +
> + 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 e5312ea..b72678f 100644
> --- a/arch/arm64/include/asm/psci.h
> +++ b/arch/arm64/include/asm/psci.h
> @@ -16,4 +16,16 @@
>
> int psci_init(void);
>
> +/* PSCI Function ID's for ARM64 as per PSCI spec v0.2 */
> +#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 /* __ASM_PSCI_H */
> diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
> index 4f97db3..d4cff4e 100644
> --- a/arch/arm64/kernel/psci.c
> +++ b/arch/arm64/kernel/psci.c
> @@ -45,12 +45,14 @@ struct psci_operations {
> 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_MAX,
> };
>
> @@ -128,6 +130,20 @@ 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;
> + u32 fn;
> +
> + fn = PSCI_ID_VERSION;
> + err = invoke_psci_fn(fn, 0, 0, 0);
> + return err;
> +}
> +
> static int psci_cpu_suspend(struct psci_power_state state,
> unsigned long entry_point)
> {
> @@ -171,26 +187,64 @@ 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", },
> - {},
> -};
> +/*
> + * PSCI Function ID's for v0.2+ are well defined so use
> + * static values.
> + */
> +static int psci_static_init(struct device_node *np)
> +{
> + const char *method;
> + int err = 0;
>
> -int __init psci_init(void)
> + 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;
> + }
> +
> + pr_info("Using static PSCIv0.2+ 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;
> +
> +out_put_node:
> + of_node_put(np);
> + return err;
Can any of this code not be shared between arm and arm64?
Looks almost identical.
-Christoffer
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