From 0654cf05d17bc4d296a53a8bc7d107bc8a795f2e Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 4 Sep 2021 15:51:45 +0200 Subject: ACPI: CPPC: Introduce cppc_get_nominal_perf() On some systems the nominal_perf value retrieved via CPPC is just a constant and fetching it doesn't require accessing any registers, so if it is the only CPPC capability that's needed, it is wasteful to run cppc_get_perf_caps() in order to get just that value alone, especially when this is done for CPUs other than the one running the code. For this reason, introduce cppc_get_nominal_perf() allowing nominal_perf to be obtained individually, by generalizing the existing cppc_get_desired_perf() (and renaming it) so it can be used to retrieve any specific CPPC capability value. While at it, clean up the cppc_get_desired_perf() kerneldoc comment a bit. Signed-off-by: Rafael J. Wysocki --- drivers/acpi/cppc_acpi.c | 47 +++++++++++++++++++++++++++++++---------------- 1 file changed, 31 insertions(+), 16 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index a4d4eebba1da..bd482108310c 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -1008,23 +1008,14 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) return ret_val; } -/** - * cppc_get_desired_perf - Get the value of desired performance register. - * @cpunum: CPU from which to get desired performance. - * @desired_perf: address of a variable to store the returned desired performance - * - * Return: 0 for success, -EIO otherwise. - */ -int cppc_get_desired_perf(int cpunum, u64 *desired_perf) +static int cppc_get_perf(int cpunum, enum cppc_regs reg_idx, u64 *perf) { struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpunum); - int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum); - struct cpc_register_resource *desired_reg; - struct cppc_pcc_data *pcc_ss_data = NULL; - - desired_reg = &cpc_desc->cpc_regs[DESIRED_PERF]; + struct cpc_register_resource *reg = &cpc_desc->cpc_regs[reg_idx]; - if (CPC_IN_PCC(desired_reg)) { + if (CPC_IN_PCC(reg)) { + int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum); + struct cppc_pcc_data *pcc_ss_data = NULL; int ret = 0; if (pcc_ss_id < 0) @@ -1035,7 +1026,7 @@ int cppc_get_desired_perf(int cpunum, u64 *desired_perf) down_write(&pcc_ss_data->pcc_lock); if (send_pcc_cmd(pcc_ss_id, CMD_READ) >= 0) - cpc_read(cpunum, desired_reg, desired_perf); + cpc_read(cpunum, reg, perf); else ret = -EIO; @@ -1044,12 +1035,36 @@ int cppc_get_desired_perf(int cpunum, u64 *desired_perf) return ret; } - cpc_read(cpunum, desired_reg, desired_perf); + cpc_read(cpunum, reg, perf); return 0; } + +/** + * cppc_get_desired_perf - Get the desired performance register value. + * @cpunum: CPU from which to get desired performance. + * @desired_perf: Return address. + * + * Return: 0 for success, -EIO otherwise. + */ +int cppc_get_desired_perf(int cpunum, u64 *desired_perf) +{ + return cppc_get_perf(cpunum, DESIRED_PERF, desired_perf); +} EXPORT_SYMBOL_GPL(cppc_get_desired_perf); +/** + * cppc_get_nominal_perf - Get the nominal performance register value. + * @cpunum: CPU from which to get nominal performance. + * @nominal_perf: Return address. + * + * Return: 0 for success, -EIO otherwise. + */ +int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf) +{ + return cppc_get_perf(cpunum, NOMINAL_PERF, nominal_perf); +} + /** * cppc_get_perf_caps - Get a CPU's performance capabilities. * @cpunum: CPU from which to get capabilities info. -- cgit v1.2.3