Re: [PATCH 08/15] hwmon, fam15h_power: add max compute unit accumulated power

Guenter Roeck
2015-08-27T14:56:40Z

On 08/27/2015 01:07 AM, Huang Rui wrote:
> This patch adds a member in fam15h_power_data which specifies the
> maximum accumulated power in a compute unit.
>
> Signed-off-by: Huang Rui <ray.huang@amd.com>
> ---
> drivers/hwmon/fam15h_power.c | 24 ++++++++++++++++++++----
> 1 file changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/hwmon/fam15h_power.c b/drivers/hwmon/fam15h_power.c
> index d6efcf6..fdfa18e 100644
> --- a/drivers/hwmon/fam15h_power.c
> +++ b/drivers/hwmon/fam15h_power.c
> @@ -26,6 +26,7 @@
> #include <linux/pci.h>
> #include <linux/bitops.h>
> #include <asm/processor.h>
> +#include <asm/msr.h>
>
> MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor");
> MODULE_AUTHOR("Andreas Herrmann <herrmann.der.user@googlemail.com>");
> @@ -43,12 +44,16 @@ MODULE_LICENSE("GPL");
>
> #define FAM15H_MIN_POWER_GROUPS 2
>
> +#define MSR_F15H_CU_MAX_PWR_ACCUMULATOR 0xc001007b
> +
> struct fam15h_power_data {
> struct pci_dev *pdev;
> unsigned int tdp_to_watts;
> unsigned int base_tdp;
> unsigned int processor_pwr_watts;
> unsigned int cpu_pwr_sample_ratio;
> + /* maximum accumulated power of a compute unit */
> + u64 max_cu_acc_power;
> };
>
> static ssize_t show_power(struct device *dev,
> @@ -199,8 +204,8 @@ static int fam15h_power_resume(struct pci_dev *pdev)
> #define fam15h_power_resume NULL
> #endif
>
> -static void fam15h_power_init_data(struct pci_dev *f4,
> - struct fam15h_power_data *data)
> +static int fam15h_power_init_data(struct pci_dev *f4,
> + struct fam15h_power_data *data)
> {
> u32 val, eax, ebx, ecx, edx;
> u64 tmp;
> @@ -228,7 +233,7 @@ static void fam15h_power_init_data(struct pci_dev *f4,
>
> /* CPUID Fn8000_0007:EDX[12] indicates to support accumulated power */
> if (!(edx & BIT(12)))
> - return;
> + return 0;
>
> /*
> * detemine the ratio of the compute unit power accumulator
> @@ -236,6 +241,15 @@ static void fam15h_power_init_data(struct pci_dev *f4,
> * Fn8000_0007:ECX
> */
> data->cpu_pwr_sample_ratio = ecx;
> +
> + if (rdmsrl_safe(MSR_F15H_CU_MAX_PWR_ACCUMULATOR, &tmp)) {
> + pr_err("Failed to read max compute unit power accumulator MSR\n");
> + return -ENODEV;
> + }
> +
> + data->max_cu_acc_power = tmp;
> +
> + return 0;
> }
>
> static int fam15h_power_probe(struct pci_dev *pdev,
> @@ -262,7 +276,9 @@ static int fam15h_power_probe(struct pci_dev *pdev,
> if (fam15h_power_init_attrs(pdev))
> return -ENOMEM;
>
> - fam15h_power_init_data(pdev, data);
> + if (fam15h_power_init_data(pdev, data))
> + return -ENODEV;
> +
This should return the error code from fam15h_power_init_data().

Thanks,
Guenter