diff --git a/drivers/hwmon/fam15h_power.c b/drivers/hwmon/fam15h_power.c index 41174903009c..e80ee23b62d3 100644 --- a/drivers/hwmon/fam15h_power.c +++ b/drivers/hwmon/fam15h_power.c @@ -46,6 +46,7 @@ struct fam15h_power_data { unsigned int tdp_to_watts; unsigned int base_tdp; unsigned int processor_pwr_watts; + unsigned int cpu_pwr_sample_ratio; }; static ssize_t show_power(struct device *dev, @@ -188,7 +189,7 @@ static int fam15h_power_resume(struct pci_dev *pdev) static void fam15h_power_init_data(struct pci_dev *f4, struct fam15h_power_data *data) { - u32 val; + u32 val, eax, ebx, ecx, edx; u64 tmp; pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val); @@ -209,6 +210,19 @@ static void fam15h_power_init_data(struct pci_dev *f4, /* convert to microWatt */ data->processor_pwr_watts = (tmp * 15625) >> 10; + + cpuid(0x80000007, &eax, &ebx, &ecx, &edx); + + /* CPUID Fn8000_0007:EDX[12] indicates to support accumulated power */ + if (!(edx & BIT(12))) + return; + + /* + * determine the ratio of the compute unit power accumulator + * sample period to the PTSC counter period by executing CPUID + * Fn8000_0007:ECX + */ + data->cpu_pwr_sample_ratio = ecx; } static int fam15h_power_probe(struct pci_dev *pdev,