diff options
Diffstat (limited to 'drivers/acpi/cppc_acpi.c')
| -rw-r--r-- | drivers/acpi/cppc_acpi.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 1e15a9f25ae9..093675b1a1ff 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -424,6 +424,9 @@ bool acpi_cpc_valid(void) struct cpc_desc *cpc_ptr; int cpu; + if (acpi_disabled) + return false; + for_each_present_cpu(cpu) { cpc_ptr = per_cpu(cpc_desc_ptr, cpu); if (!cpc_ptr) @@ -1241,6 +1244,48 @@ out_err: EXPORT_SYMBOL_GPL(cppc_get_perf_caps); /** + * cppc_perf_ctrs_in_pcc - Check if any perf counters are in a PCC region. + * + * CPPC has flexibility about how CPU performance counters are accessed. + * One of the choices is PCC regions, which can have a high access latency. This + * routine allows callers of cppc_get_perf_ctrs() to know this ahead of time. + * + * Return: true if any of the counters are in PCC regions, false otherwise + */ +bool cppc_perf_ctrs_in_pcc(void) +{ + int cpu; + + for_each_present_cpu(cpu) { + struct cpc_register_resource *ref_perf_reg; + struct cpc_desc *cpc_desc; + + cpc_desc = per_cpu(cpc_desc_ptr, cpu); + + if (CPC_IN_PCC(&cpc_desc->cpc_regs[DELIVERED_CTR]) || + CPC_IN_PCC(&cpc_desc->cpc_regs[REFERENCE_CTR]) || + CPC_IN_PCC(&cpc_desc->cpc_regs[CTR_WRAP_TIME])) + return true; + + + ref_perf_reg = &cpc_desc->cpc_regs[REFERENCE_PERF]; + + /* + * If reference perf register is not supported then we should + * use the nominal perf value + */ + if (!CPC_SUPPORTED(ref_perf_reg)) + ref_perf_reg = &cpc_desc->cpc_regs[NOMINAL_PERF]; + + if (CPC_IN_PCC(ref_perf_reg)) + return true; + } + + return false; +} +EXPORT_SYMBOL_GPL(cppc_perf_ctrs_in_pcc); + +/** * cppc_get_perf_ctrs - Read a CPU's performance feedback counters. * @cpunum: CPU from which to read counters. * @perf_fb_ctrs: ptr to cppc_perf_fb_ctrs. See cppc_acpi.h |