diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index d9ce4b162e2ce0533039cbe2d5ef4704ecb24642..e57f567ee9ad979fcfa3f2d704fa871d4345c908 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -1050,6 +1050,48 @@ 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) +{ + 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]; + + if (CPC_IN_PCC(desired_reg)) { + int ret = 0; + + if (pcc_ss_id < 0) + return -EIO; + + pcc_ss_data = pcc_data[pcc_ss_id]; + + down_write(&pcc_ss_data->pcc_lock); + + if (send_pcc_cmd(pcc_ss_id, CMD_READ) >= 0) + cpc_read(cpunum, desired_reg, desired_perf); + else + ret = -EIO; + + up_write(&pcc_ss_data->pcc_lock); + + return ret; + } + + cpc_read(cpunum, desired_reg, desired_perf); + + return 0; +} +EXPORT_SYMBOL_GPL(cppc_get_desired_perf); + /** * cppc_get_perf_caps - Get a CPUs performance capabilities. * @cpunum: CPU from which to get capabilities info. diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h index 8e0b8250a139975ffd49cea4e2ce724ba464bd9d..cc894ecd3dbfefb3d7020e528f230d61e625464e 100644 --- a/include/acpi/cppc_acpi.h +++ b/include/acpi/cppc_acpi.h @@ -136,6 +136,7 @@ struct cppc_cpudata { cpumask_var_t shared_cpu_map; }; +extern int cppc_get_desired_perf(int cpunum, u64 *desired_perf); extern int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs); extern int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls); extern int cppc_get_perf_caps(int cpu, struct cppc_perf_caps *caps);