| Message ID | 1405958786-17243-5-git-send-email-lorenzo.pieralisi@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 21 July 2014 12:06, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > This patch implements the cpu_suspend cpu operations method through > the PSCI CPU SUSPEND API. The PSCI implementation translates the idle state > index passed by the cpu_suspend core call into a valid PSCI state according to > the PSCI states initialized at boot through the cpu_init_idle() CPU > operations hook. > > Entry point is set to cpu_resume physical address, that represents the > default kernel execution address following a CPU reset; for standby > states the entry point address is useless and will therefore be ignored > by the PSCI implementation. > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > --- > arch/arm64/kernel/psci.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 89 insertions(+) > > diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c > index a623c44..bbdf41d 100644 > --- a/arch/arm64/kernel/psci.c > +++ b/arch/arm64/kernel/psci.c > @@ -21,6 +21,7 @@ > #include <linux/reboot.h> > #include <linux/pm.h> > #include <linux/delay.h> > +#include <linux/slab.h> > #include <uapi/linux/psci.h> > > #include <asm/compiler.h> > @@ -28,6 +29,7 @@ > #include <asm/errno.h> > #include <asm/psci.h> > #include <asm/smp_plat.h> > +#include <asm/suspend.h> > #include <asm/system_misc.h> > > #define PSCI_POWER_STATE_TYPE_STANDBY 0 > @@ -65,6 +67,8 @@ enum psci_function { > PSCI_FN_MAX, > }; > > +static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state); > + > static u32 psci_function_id[PSCI_FN_MAX]; > > static int psci_to_linux_errno(int errno) > @@ -93,6 +97,18 @@ static u32 psci_power_state_pack(struct psci_power_state state) > & PSCI_0_2_POWER_STATE_AFFL_MASK); > } > > +static void psci_power_state_unpack(u32 power_state, > + struct psci_power_state *state) > +{ > + state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >> > + PSCI_0_2_POWER_STATE_ID_SHIFT; > + state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >> > + PSCI_0_2_POWER_STATE_TYPE_SHIFT; > + state->affinity_level = > + (power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >> > + PSCI_0_2_POWER_STATE_AFFL_SHIFT; > +} > + > /* > * The following two functions are invoked via the invoke_psci_fn pointer > * and will not be inlined, allowing us to piggyback on the AAPCS. > @@ -199,6 +215,61 @@ static int psci_migrate_info_type(void) > return err; > } > > +static int cpu_psci_cpu_init_idle(struct device_node *cpu_node, > + unsigned int cpu) > +{ > + int i, ret, count = 0; > + struct psci_power_state *psci_states; > + struct device_node *state_node; > + > + /* > + * If the PSCI cpu_suspend function hook has not been initialized > + * idle states must not be enabled, so bail out > + */ > + if (!psci_ops.cpu_suspend) > + return -EOPNOTSUPP; > + > + /* Count idle states */ > + while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states", > + count))) > + count++; > + > + if (!count) > + return -ENODEV; > + > + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); > + if (!psci_states) { > + pr_warn("idle state psci_state allocation failed\n"); > + return -ENOMEM; > + } > + > + for (i = 0; i < count; i++) { > + u32 psci_power_state; > + > + state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i); > + > + ret = of_property_read_u32(state_node, > + "arm,psci-suspend-param", > + &psci_power_state); > + if (ret) { > + pr_warn(" * %s missing arm,psci-suspend-param property\n", > + state_node->full_name); > + goto free_mem; > + } > + > + pr_debug("psci-power-state %#x index %d\n", psci_power_state, > + i); > + psci_power_state_unpack(psci_power_state, &psci_states[i]); > + } > + /* Idle states parsed correctly, initialize per-cpu pointer */ > + per_cpu(psci_power_state, cpu) = psci_states; > + return 0; > + > +free_mem: > + kfree(psci_states); > + return ret; > +} > + > static int get_set_conduit_method(struct device_node *np) > { > const char *method; > @@ -436,8 +507,23 @@ static int cpu_psci_cpu_kill(unsigned int cpu) > #endif > #endif > > +static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index) > +{ > + struct psci_power_state *state = __get_cpu_var(psci_power_state); > + /* > + * idle state index 0 corresponds to wfi, should never be called > + * from the cpu_suspend operations > + */ > + if (WARN_ON_ONCE(!index)) > + return -EINVAL; > + > + return psci_ops.cpu_suspend(state[index - 1], > + virt_to_phys(cpu_resume)); > +} > + > const struct cpu_operations cpu_psci_ops = { > .name = "psci", > + .cpu_init_idle = cpu_psci_cpu_init_idle, > #ifdef CONFIG_SMP > .cpu_init = cpu_psci_cpu_init, > .cpu_prepare = cpu_psci_cpu_prepare, > @@ -448,5 +534,8 @@ const struct cpu_operations cpu_psci_ops = { > .cpu_kill = cpu_psci_cpu_kill, > #endif > #endif > +#ifdef CONFIG_ARM64_CPU_SUSPEND > + .cpu_suspend = cpu_psci_cpu_suspend, > +#endif > }; > > -- > 1.9.1 Reviewed-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> > > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index a623c44..bbdf41d 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -21,6 +21,7 @@ #include <linux/reboot.h> #include <linux/pm.h> #include <linux/delay.h> +#include <linux/slab.h> #include <uapi/linux/psci.h> #include <asm/compiler.h> @@ -28,6 +29,7 @@ #include <asm/errno.h> #include <asm/psci.h> #include <asm/smp_plat.h> +#include <asm/suspend.h> #include <asm/system_misc.h> #define PSCI_POWER_STATE_TYPE_STANDBY 0 @@ -65,6 +67,8 @@ enum psci_function { PSCI_FN_MAX, }; +static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state); + static u32 psci_function_id[PSCI_FN_MAX]; static int psci_to_linux_errno(int errno) @@ -93,6 +97,18 @@ static u32 psci_power_state_pack(struct psci_power_state state) & PSCI_0_2_POWER_STATE_AFFL_MASK); } +static void psci_power_state_unpack(u32 power_state, + struct psci_power_state *state) +{ + state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >> + PSCI_0_2_POWER_STATE_ID_SHIFT; + state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >> + PSCI_0_2_POWER_STATE_TYPE_SHIFT; + state->affinity_level = + (power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >> + PSCI_0_2_POWER_STATE_AFFL_SHIFT; +} + /* * The following two functions are invoked via the invoke_psci_fn pointer * and will not be inlined, allowing us to piggyback on the AAPCS. @@ -199,6 +215,61 @@ static int psci_migrate_info_type(void) return err; } +static int cpu_psci_cpu_init_idle(struct device_node *cpu_node, + unsigned int cpu) +{ + int i, ret, count = 0; + struct psci_power_state *psci_states; + struct device_node *state_node; + + /* + * If the PSCI cpu_suspend function hook has not been initialized + * idle states must not be enabled, so bail out + */ + if (!psci_ops.cpu_suspend) + return -EOPNOTSUPP; + + /* Count idle states */ + while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states", + count))) + count++; + + if (!count) + return -ENODEV; + + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); + if (!psci_states) { + pr_warn("idle state psci_state allocation failed\n"); + return -ENOMEM; + } + + for (i = 0; i < count; i++) { + u32 psci_power_state; + + state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i); + + ret = of_property_read_u32(state_node, + "arm,psci-suspend-param", + &psci_power_state); + if (ret) { + pr_warn(" * %s missing arm,psci-suspend-param property\n", + state_node->full_name); + goto free_mem; + } + + pr_debug("psci-power-state %#x index %d\n", psci_power_state, + i); + psci_power_state_unpack(psci_power_state, &psci_states[i]); + } + /* Idle states parsed correctly, initialize per-cpu pointer */ + per_cpu(psci_power_state, cpu) = psci_states; + return 0; + +free_mem: + kfree(psci_states); + return ret; +} + static int get_set_conduit_method(struct device_node *np) { const char *method; @@ -436,8 +507,23 @@ static int cpu_psci_cpu_kill(unsigned int cpu) #endif #endif +static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index) +{ + struct psci_power_state *state = __get_cpu_var(psci_power_state); + /* + * idle state index 0 corresponds to wfi, should never be called + * from the cpu_suspend operations + */ + if (WARN_ON_ONCE(!index)) + return -EINVAL; + + return psci_ops.cpu_suspend(state[index - 1], + virt_to_phys(cpu_resume)); +} + const struct cpu_operations cpu_psci_ops = { .name = "psci", + .cpu_init_idle = cpu_psci_cpu_init_idle, #ifdef CONFIG_SMP .cpu_init = cpu_psci_cpu_init, .cpu_prepare = cpu_psci_cpu_prepare, @@ -448,5 +534,8 @@ const struct cpu_operations cpu_psci_ops = { .cpu_kill = cpu_psci_cpu_kill, #endif #endif +#ifdef CONFIG_ARM64_CPU_SUSPEND + .cpu_suspend = cpu_psci_cpu_suspend, +#endif };
This patch implements the cpu_suspend cpu operations method through the PSCI CPU SUSPEND API. The PSCI implementation translates the idle state index passed by the cpu_suspend core call into a valid PSCI state according to the PSCI states initialized at boot through the cpu_init_idle() CPU operations hook. Entry point is set to cpu_resume physical address, that represents the default kernel execution address following a CPU reset; for standby states the entry point address is useless and will therefore be ignored by the PSCI implementation. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> --- arch/arm64/kernel/psci.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 89 insertions(+)