On Thu, Jan 11, 2024 at 11:19:49AM +0100, Andrew Jones wrote: > On Thu, Jan 11, 2024 at 03:00:58PM +0530, Sunil V L wrote: > > Add required callbacks to support Low Power Idle (LPI) on ACPI based > > RISC-V platforms. > > > > Signed-off-by: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx> > > --- > > drivers/cpuidle/cpuidle-riscv-sbi.c | 78 +++++++++++++++++++++++++++++ > > 1 file changed, 78 insertions(+) > > > > diff --git a/drivers/cpuidle/cpuidle-riscv-sbi.c b/drivers/cpuidle/cpuidle-riscv-sbi.c > > index e8094fc92491..cea67a54ab39 100644 > > --- a/drivers/cpuidle/cpuidle-riscv-sbi.c > > +++ b/drivers/cpuidle/cpuidle-riscv-sbi.c > > @@ -632,3 +632,81 @@ static int __init sbi_cpuidle_init(void) > > return 0; > > } > > device_initcall(sbi_cpuidle_init); > > + > > +#ifdef CONFIG_ACPI_PROCESSOR_IDLE > > + > > +#include <linux/acpi.h> > > +#include <acpi/processor.h> > > + > > +#define RISCV_FFH_LPI_TYPE_MASK 0x1000000000000000ULL > > +#define RISCV_FFH_LPI_RSVD_MASK 0x0FFFFFFF00000000ULL > > GENMASK might look nicer and the type mask is 0xF000000000000000ULL, > where 0x1000000000000000ULL means that the type is an SBI identifier. > We need both defined > > #define RISCV_FFH_LPI_TYPE_MASK 0xF000000000000000ULL > #define RISCV_FFH_LPI_TYPE_SBI 0x1000000000000000ULL > Sure. Let me use GENMASK and define both MASK and SBI type. > as I point out below. > > > + > > +static int acpi_cpu_init_idle(unsigned int cpu) > > +{ > > + int i; > > + struct acpi_lpi_state *lpi; > > + struct acpi_processor *pr = per_cpu(processors, cpu); > > + > > + if (unlikely(!pr || !pr->flags.has_lpi)) > > + return -EINVAL; > > + > > + /* > > + * The SBI HSM suspend function is only available when: > > + * 1) SBI version is 0.3 or higher > > + * 2) SBI HSM extension is available > > + */ > > + if (sbi_spec_version < sbi_mk_version(0, 3) || > > + !sbi_probe_extension(SBI_EXT_HSM)) { > > + pr_warn("HSM suspend not available\n"); > > The comment and these lines match what's done in sbi_cpuidle_init(). > How about a static helper function to avoid duplication? > Sure. > > + return -EINVAL; > > + } > > + > > + if (pr->power.count <= 1) > > + return -ENODEV; > > + > > + for (i = 1; i < pr->power.count; i++) { > > + u32 state; > > + > > + lpi = &pr->power.lpi_states[i]; > > + > > + /* Validate Entry Method as per FFH spec. > > + * bits[63:60] should be 0x1 > > + * bits[59:32] should be 0x0 > > + * bits[31:0] represent a SBI power_state > ^ an > > > + */ > > Comment block needs opening wing (/*) > Okay. > > + if (!(lpi->address & RISCV_FFH_LPI_TYPE_MASK) || > > This should be (lpi->address & RISCV_FFH_LPI_TYPE_MASK) != RISCV_FFH_LPI_TYPE_SBI > Sure. Let me send v2 in couple of days with these changes. Thanks! Sunil > > + (lpi->address & RISCV_FFH_LPI_RSVD_MASK)) { > > + pr_warn("Invalid LPI entry method %#llx\n", lpi->address); > > + return -EINVAL; > > + } > > + > > + state = lpi->address; > > + if (!sbi_suspend_state_is_valid(state)) { > > + pr_warn("Invalid SBI power state %#x\n", state); > > + return -EINVAL; > > + } > > + } > > + > > + return 0; > > +} > > + > > +int acpi_processor_ffh_lpi_probe(unsigned int cpu) > > +{ > > + return acpi_cpu_init_idle(cpu); > > +} > > + > > +int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) > > +{ > > + u32 state = lpi->address; > > + > > + if (state & SBI_HSM_SUSP_NON_RET_BIT) > > + return CPU_PM_CPU_IDLE_ENTER_PARAM(sbi_suspend, > > + lpi->index, > > + state); > > + else > > + return CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM(sbi_suspend, > > + lpi->index, > > + state); > > +} > > + > > +#endif > > -- > > 2.34.1 > > > > Thanks, > drew