diff options
author | Perry Yuan <Perry.Yuan@amd.com> | 2023-01-31 12:00:06 +0300 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2023-02-03 23:59:41 +0300 |
commit | 7bc1fcd399018245575974508c26e882da0bd915 (patch) | |
tree | 94a7d0ec304f8bdc474594c8fb4fb31bda3e2627 /drivers/acpi/cppc_acpi.c | |
parent | 38a29e5834eba1e71bc4aab82b09ac065af62b80 (diff) | |
download | linux-7bc1fcd399018245575974508c26e882da0bd915.tar.xz |
ACPI: CPPC: Add AMD pstate energy performance preference cppc control
Add support for setting and querying EPP preferences to the generic
CPPC driver. This enables downstream drivers such as amd-pstate to discover
and use these values.
Downstream drivers that want to use the new symbols cppc_get_epp_caps
and cppc_set_epp_perf for querying and setting EPP preferences will need
to call cppc_set_epp_perf to enable the EPP function firstly.
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/cppc_acpi.c')
-rw-r--r-- | drivers/acpi/cppc_acpi.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 0f17b1c32718..02d83c807271 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -1154,6 +1154,19 @@ int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf) } /** + * cppc_get_epp_perf - Get the epp register value. + * @cpunum: CPU from which to get epp preference value. + * @epp_perf: Return address. + * + * Return: 0 for success, -EIO otherwise. + */ +int cppc_get_epp_perf(int cpunum, u64 *epp_perf) +{ + return cppc_get_perf(cpunum, ENERGY_PERF, epp_perf); +} +EXPORT_SYMBOL_GPL(cppc_get_epp_perf); + +/** * cppc_get_perf_caps - Get a CPU's performance capabilities. * @cpunum: CPU from which to get capabilities info. * @perf_caps: ptr to cppc_perf_caps. See cppc_acpi.h @@ -1365,6 +1378,60 @@ out_err: } EXPORT_SYMBOL_GPL(cppc_get_perf_ctrs); +/* + * Set Energy Performance Preference Register value through + * Performance Controls Interface + */ +int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable) +{ + int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); + struct cpc_register_resource *epp_set_reg; + struct cpc_register_resource *auto_sel_reg; + struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); + struct cppc_pcc_data *pcc_ss_data = NULL; + int ret; + + if (!cpc_desc) { + pr_debug("No CPC descriptor for CPU:%d\n", cpu); + return -ENODEV; + } + + auto_sel_reg = &cpc_desc->cpc_regs[AUTO_SEL_ENABLE]; + epp_set_reg = &cpc_desc->cpc_regs[ENERGY_PERF]; + + if (CPC_IN_PCC(epp_set_reg) || CPC_IN_PCC(auto_sel_reg)) { + if (pcc_ss_id < 0) { + pr_debug("Invalid pcc_ss_id for CPU:%d\n", cpu); + return -ENODEV; + } + + if (CPC_SUPPORTED(auto_sel_reg)) { + ret = cpc_write(cpu, auto_sel_reg, enable); + if (ret) + return ret; + } + + if (CPC_SUPPORTED(epp_set_reg)) { + ret = cpc_write(cpu, epp_set_reg, perf_ctrls->energy_perf); + if (ret) + return ret; + } + + pcc_ss_data = pcc_data[pcc_ss_id]; + + down_write(&pcc_ss_data->pcc_lock); + /* after writing CPC, transfer the ownership of PCC to platform */ + ret = send_pcc_cmd(pcc_ss_id, CMD_WRITE); + up_write(&pcc_ss_data->pcc_lock); + } else { + ret = -ENOTSUPP; + pr_debug("_CPC in PCC is not supported\n"); + } + + return ret; +} +EXPORT_SYMBOL_GPL(cppc_set_epp_perf); + /** * cppc_set_enable - Set to enable CPPC on the processor by writing the * Continuous Performance Control package EnableRegister field. |