Hi Sudeep, -----Original Message----- From: Sudeep Holla [mailto:[email protected]] Sent: Wednesday, May 11, 2016 9:08 PM To: [email protected]; Rafael J. Wysocki <[email protected]> Cc: Sudeep Holla <[email protected]>; [email protected]; Sajjan, Vikas C <[email protected]>; Lakshminarasimha, Sunil Vishwanathpur <[email protected]>; Prashanth Prakash <[email protected]>; Ashwin Chaugule <[email protected]>; Al Stone <[email protected]>; Lorenzo Pieralisi <[email protected]>; Mark Rutland <[email protected]>; [email protected] Subject: [PATCH v5 4/5] arm64: add support for ACPI Low Power Idle(LPI)
This patch adds appropriate callbacks to support ACPI Low Power Idle (LPI) on ARM64. Cc: Lorenzo Pieralisi <[email protected]> Cc: Mark Rutland <[email protected]> Cc: [email protected] Signed-off-by: Sudeep Holla <[email protected]> --- arch/arm64/kernel/acpi.c | 48 +++++++++++++++++++++++++++++++++++++++++ drivers/firmware/psci.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 104 insertions(+) diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index d1ce8e2f98b9..bf82ce5c8fce 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -18,6 +18,7 @@ #include <linux/acpi.h> #include <linux/bootmem.h> #include <linux/cpumask.h> +#include <linux/cpu_pm.h> #include <linux/init.h> #include <linux/irq.h> #include <linux/irqdomain.h> @@ -25,6 +26,9 @@ #include <linux/of_fdt.h> #include <linux/smp.h> +#include <acpi/processor.h> + +#include <asm/cpuidle.h> #include <asm/cputype.h> #include <asm/cpu_ops.h> #include <asm/smp_plat.h> @@ -211,6 +215,50 @@ void __init acpi_boot_table_init(void) } } +int acpi_processor_ffh_lpi_probe(unsigned int cpu) { + return arm_cpuidle_init(cpu); +} + +#define ACPI_FFH_LPI_ARM_FLAGS_CORE_CONTEXT BIT(0) +#define ACPI_FFH_LPI_ARM_FLAGS_TRACE_CONTEXT BIT(1) +#define ACPI_FFH_LPI_ARM_FLAGS_GICR_CONTEXT BIT(2) +#define ACPI_FFH_LPI_ARM_FLAGS_GICD_CONTEXT BIT(3) +#define ACPI_FFH_LPI_ARM_FLAGS_ALL_CONTEXT \ + (ACPI_FFH_LPI_ARM_FLAGS_CORE_CONTEXT | \ + ACPI_FFH_LPI_ARM_FLAGS_TRACE_CONTEXT | \ + ACPI_FFH_LPI_ARM_FLAGS_GICR_CONTEXT | \ + ACPI_FFH_LPI_ARM_FLAGS_GICD_CONTEXT) + +struct acpi_lpi_state *lpi; +int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi, int idx) { + int ret = 0; + bool save_ctx = lpi->arch_flags & ACPI_FFH_LPI_ARM_FLAGS_ALL_CONTEXT; + + if (!idx) { + cpu_do_idle(); + return idx; + } + + /* TODO cpu_pm_{enter,exit} can be done in generic code ? */ + if (save_ctx) + ret = cpu_pm_enter(); + if (!ret) { + /* + * Pass idle state index to cpu_suspend which in turn will + * call the CPU ops suspend protocol with idle index as a + * parameter. + */ + ret = arm_cpuidle_suspend(idx); + + if (save_ctx) + cpu_pm_exit(); + } + + return ret ? -1 : idx; +} + #ifdef CONFIG_ACPI_APEI pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr) { diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c index fa4ea22ca12e..e06bfee68e1d 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> @@ -310,11 +311,66 @@ static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu) 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_processor *pr; + struct acpi_lpi_state *lpi; + + pr = per_cpu(processors, cpu); + if (unlikely(!pr || !pr->flags.has_lpi)) Any particular reason for _not_ considering CST flag here. Or you are planning to add CST support in some other patch set. + return -EINVAL; + + /* + * 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 = pr->power.count - 1; + if (!count) + 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]; Same case here too. + state = lpi->address & 0xFFFFFFFF; + 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 (!acpi_disabled) + return psci_acpi_cpu_init_idle(cpu); + cpu_node = of_get_cpu_node(cpu, NULL); if (!cpu_node) return -ENODEV; -- 1.9.1
