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

Huang Rui
2015-08-27T08:25:36Z

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;
+
data->pdev = pdev;

hwmon_dev = devm_hwmon_device_register_with_groups(dev, "fam15h_power",
--
1.9.1