Dear Sudeep, On Tue, 19 Apr 2016 13:30:12 +0100 Sudeep Holla wrote:
> This patch adds appropriate callbacks to support ACPI Low Power Idle > (LPI) on ARM64. > > It also selects ARCH_SUPPORTS_ACPI_PROCESSOR_LPI if ACPI is enabled > on ARM64. > > Cc: Lorenzo Pieralisi <[email protected]> > Cc: Mark Rutland <[email protected]> > Cc: [email protected] > Signed-off-by: Sudeep Holla <[email protected]> > --- > arch/arm64/Kconfig | 1 + > arch/arm64/kernel/acpi.c | 34 ++++++++++++++++++++++++++++++++++ > drivers/firmware/psci.c | 48 > ++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 83 insertions(+) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 4f436220384f..e7536540387d 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -10,6 +10,7 @@ config ARM64 > select ARCH_HAS_SG_CHAIN > select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST > select ARCH_USE_CMPXCHG_LOCKREF > + select ARCH_SUPPORTS_ACPI_PROCESSOR_LPI if ACPI > select ARCH_SUPPORTS_ATOMIC_RMW > select ARCH_WANT_OPTIONAL_GPIOLIB > select ARCH_WANT_COMPAT_IPC_PARSE_VERSION > diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c > index d1ce8e2f98b9..3c05ad5957be 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> > @@ -25,9 +26,11 @@ > #include <linux/of_fdt.h> > #include <linux/smp.h> > > +#include <asm/cpuidle.h> > #include <asm/cputype.h> > #include <asm/cpu_ops.h> > #include <asm/smp_plat.h> > +#include <acpi/processor.h> It's better to keep headers alphabetic sorted > > #ifdef CONFIG_ACPI_APEI > # include <linux/efi.h> > @@ -211,6 +214,37 @@ void __init acpi_boot_table_init(void) > } > } > > +int acpi_processor_ffh_lpi_probe(unsigned int cpu) > +{ > + return arm_cpuidle_init(cpu); > +} > + > +struct acpi_processor_lpi *lpi; > +int acpi_processor_ffh_lpi_enter(struct acpi_processor_lpi *lpi, int idx) > +{ > + int ret; > + > + if (!idx) { > + cpu_do_idle(); > + return idx; > + } > + > + /* TODO cpu_pm_{enter,exit} can be done in generic code ? */ > + 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); > + > + 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 af6c5c839568..70cf2a500d4b 100644 > --- a/drivers/firmware/psci.c > +++ b/drivers/firmware/psci.c > @@ -24,6 +24,7 @@ > #include <linux/reboot.h> > #include <linux/slab.h> > #include <linux/suspend.h> > +#include <linux/acpi.h> same here > > #include <uapi/linux/psci.h> > > @@ -32,6 +33,7 @@ > #include <asm/system_misc.h> > #include <asm/smp_plat.h> > #include <asm/suspend.h> > +#include <acpi/processor.h> ditto > > /* > * While a 64-bit OS can make calls with SMC32 calling conventions, for some > @@ -316,8 +318,54 @@ static int psci_dt_cpu_init_idle(unsigned int cpu) > return ret; > } > > +static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) > +{ > + int i, count; > + u32 *psci_states; > + struct acpi_processor *pr; > + struct acpi_processor_lpi *lpi; > + > + pr = per_cpu(processors, cpu); > + if (unlikely(!pr || !pr->flags.has_lpi)) > + 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]; > + 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; > +} > + > int psci_cpu_init_idle(unsigned int cpu) > { > + if (!acpi_disabled) > + return psci_acpi_cpu_init_idle(cpu); > + > return psci_dt_cpu_init_idle(cpu); > } >
