diff options
author | Sudeep Holla <Sudeep.Holla@arm.com> | 2016-07-19 19:52:57 +0200 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-07-21 23:29:38 +0200 |
commit | c2a25c141f4e80debd8eec3e9a5f9d25daedb54f (patch) | |
tree | 4327610767dd08bb9f3a50d961e4a19f1d4c04a2 /drivers/firmware/psci.c | |
parent | cpuidle: introduce CPU_PM_CPU_IDLE_ENTER macro for ARM{32, 64} (diff) | |
download | linux-c2a25c141f4e80debd8eec3e9a5f9d25daedb54f.tar.xz linux-c2a25c141f4e80debd8eec3e9a5f9d25daedb54f.zip |
drivers: firmware: psci: initialise idle states using ACPI LPI
This patch adds support for initialisation of PSCI CPUIdle states
from Low Power Idle(_LPI) entries in the ACPI tables when acpi is
enabled.
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/firmware/psci.c')
-rw-r--r-- | drivers/firmware/psci.c | 66 |
1 files changed, 59 insertions, 7 deletions
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c index 03e04582791c..8263429e21b8 100644 --- a/drivers/firmware/psci.c +++ b/drivers/firmware/psci.c @@ -13,6 +13,7 @@ #define pr_fmt(fmt) "psci: " fmt +#include <linux/acpi.h> #include <linux/arm-smccc.h> #include <linux/cpuidle.h> #include <linux/errno.h> @@ -256,13 +257,6 @@ static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu) u32 *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))) { @@ -310,11 +304,69 @@ free_mem: return ret; } +#ifdef CONFIG_ACPI +#include <acpi/processor.h> + +static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) +{ + int i, count; + u32 *psci_states; + struct acpi_lpi_state *lpi; + struct acpi_processor *pr = per_cpu(processors, cpu); + + if (unlikely(!pr || !pr->flags.has_lpi)) + return -EINVAL; + + count = pr->power.count - 1; + if (count <= 0) + return -ENODEV; + + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); + if (!psci_states) + return -ENOMEM; + + for (i = 0; i < count; i++) { + u32 state; + + lpi = &pr->power.lpi_states[i + 1]; + /* + * Only bits[31:0] represent a PSCI power_state while + * bits[63:32] must be 0x0 as per ARM ACPI FFH Specification + */ + state = lpi->address; + if (!psci_power_state_is_valid(state)) { + pr_warn("Invalid PSCI power state %#x\n", state); + kfree(psci_states); + return -EINVAL; + } + psci_states[i] = state; + } + /* Idle states parsed correctly, initialize per-cpu pointer */ + per_cpu(psci_power_state, cpu) = psci_states; + return 0; +} +#else +static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) +{ + return -EINVAL; +} +#endif + int psci_cpu_init_idle(unsigned int cpu) { struct device_node *cpu_node; int ret; + /* + * 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; + + if (!acpi_disabled) + return psci_acpi_cpu_init_idle(cpu); + cpu_node = of_get_cpu_node(cpu, NULL); if (!cpu_node) return -ENODEV; |