On 21-09-2023 15:55, Badal Nilawar wrote:
Expose power1_max_interval, that is the tau corresponding to PL1, as a
custom hwmon attribute. Some bit manipulation is needed because of the
format of PKG_PWR_LIM_1_TIME in
PACKAGE_RAPL_LIMIT register (1.x * power(2,y))
v2: Get rpm wake ref while accessing power1_max_interval
v3: %s/hwmon/xe_hwmon/
Signed-off-by: Badal Nilawar <badal.nilawar@xxxxxxxxx>
---
.../ABI/testing/sysfs-driver-intel-xe-hwmon | 11 ++
drivers/gpu/drm/xe/regs/xe_mchbar_regs.h | 8 +
drivers/gpu/drm/xe/xe_hwmon.c | 138 +++++++++++++++++-
3 files changed, 156 insertions(+), 1 deletion(-)
diff --git a/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon b/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
index 1a7a6c23e141..9ceb9c04b52b 100644
--- a/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
+++ b/Documentation/ABI/testing/sysfs-driver-intel-xe-hwmon
@@ -59,3 +59,14 @@ Contact: intel-xe@xxxxxxxxxxxxxxxxxxxxx
Description: RO. Energy input of device in microjoules.
Only supported for particular Intel xe graphics platforms.
+
+What: /sys/devices/.../hwmon/hwmon<i>/power1_max_interval
+Date: September 2023
+KernelVersion: 6.5
+Contact: intel-xe@xxxxxxxxxxxxxxxxxxxxx
+Description: RW. Sustained power limit interval (Tau in PL1/Tau) in
+ milliseconds over which sustained power is averaged.
+
+ Only supported for particular Intel xe graphics platforms.
+
+
diff --git a/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h b/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
index d8ecbe1858d1..519dd1067a19 100644
--- a/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
+++ b/drivers/gpu/drm/xe/regs/xe_mchbar_regs.h
@@ -22,15 +22,23 @@
#define PKG_TDP GENMASK_ULL(14, 0)
#define PKG_MIN_PWR GENMASK_ULL(30, 16)
#define PKG_MAX_PWR GENMASK_ULL(46, 32)
+#define PKG_MAX_WIN GENMASK_ULL(54, 48)
+#define PKG_MAX_WIN_X GENMASK_ULL(54, 53)
+#define PKG_MAX_WIN_Y GENMASK_ULL(52, 48)
+
#define PCU_CR_PACKAGE_POWER_SKU_UNIT XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x5938)
#define PKG_PWR_UNIT REG_GENMASK(3, 0)
#define PKG_ENERGY_UNIT REG_GENMASK(12, 8)
+#define PKG_TIME_UNIT REG_GENMASK(19, 16)
#define PCU_CR_PACKAGE_ENERGY_STATUS XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x593c)
#define PCU_CR_PACKAGE_RAPL_LIMIT XE_REG(MCHBAR_MIRROR_BASE_SNB + 0x59a0)
#define PKG_PWR_LIM_1 REG_GENMASK(14, 0)
#define PKG_PWR_LIM_1_EN REG_BIT(15)
+#define PKG_PWR_LIM_1_TIME REG_GENMASK(23, 17)
+#define PKG_PWR_LIM_1_TIME_X REG_GENMASK(23, 22)
+#define PKG_PWR_LIM_1_TIME_Y REG_GENMASK(21, 17)
#endif /* _XE_MCHBAR_REGS_H_ */
diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c
index cb75b9a386c0..dfa638942d47 100644
--- a/drivers/gpu/drm/xe/xe_hwmon.c
+++ b/drivers/gpu/drm/xe/xe_hwmon.c
@@ -38,6 +38,7 @@ enum xe_hwmon_reg_operation {
#define SF_CURR 1000 /* milliamperes */
#define SF_VOLTAGE 1000 /* millivolts */
#define SF_ENERGY 1000000 /* microjoules */
+#define SF_TIME 1000 /* milliseconds */
struct hwmon_energy_info {
u32 reg_val_prev;
@@ -50,6 +51,7 @@ struct xe_hwmon {
struct mutex hwmon_lock; /* rmw operations*/
int scl_shift_power;
int scl_shift_energy;
+ int scl_shift_time;
struct hwmon_energy_info ei; /* Energy info for energy1_input */
};
@@ -255,6 +257,138 @@ xe_hwmon_energy_get(struct xe_hwmon *hwmon, long *energy)
xe_device_mem_access_put(gt_to_xe(hwmon->gt));
}
+static ssize_t
+xe_hwmon_power1_max_interval_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct xe_hwmon *hwmon = dev_get_drvdata(dev);
+ u32 r, x, y, x_w = 2; /* 2 bits */
+ u64 tau4, out;
+
+ xe_device_mem_access_get(gt_to_xe(hwmon->gt));
+
+ xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT,
+ REG_READ, &r, 0, 0);
+
+ xe_device_mem_access_put(gt_to_xe(hwmon->gt));
+
+ x = REG_FIELD_GET(PKG_PWR_LIM_1_TIME_X, r);
+ y = REG_FIELD_GET(PKG_PWR_LIM_1_TIME_Y, r);
+ /*
+ * tau = 1.x * power(2,y), x = bits(23:22), y = bits(21:17)
+ * = (4 | x) << (y - 2)
+ * where (y - 2) ensures a 1.x fixed point representation of 1.x
+ * However because y can be < 2, we compute
+ * tau4 = (4 | x) << y
+ * but add 2 when doing the final right shift to account for units
+ */
+ tau4 = ((1 << x_w) | x) << y;
+ /* val in hwmon interface units (millisec) */
+ out = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time + x_w);
+
+ return sysfs_emit(buf, "%llu\n", out);
+}
+
+static ssize_t
+xe_hwmon_power1_max_interval_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct xe_hwmon *hwmon = dev_get_drvdata(dev);
+ u32 x, y, rxy, x_w = 2; /* 2 bits */
+ u64 tau4, r, max_win;
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 0, &val);
+ if (ret)
+ return ret;
+
+ /*
+ * Max HW supported tau in '1.x * power(2,y)' format, x = 0, y = 0x12
+ * The hwmon->scl_shift_time default of 0xa results in a max tau of 256 seconds
+ */
+#define PKG_MAX_WIN_DEFAULT 0x12ull
Do we need to determine r, x, y etc for max limit ?
Why cant we simply define MAX_LIMIT 256 ?
BR
Himal
+
+ /*
+ * val must be < max in hwmon interface units. The steps below are
+ * explained in xe_hwmon_power1_max_interval_show()
+ */
+ r = FIELD_PREP(PKG_MAX_WIN, PKG_MAX_WIN_DEFAULT);
+ x = REG_FIELD_GET(PKG_MAX_WIN_X, r);
+ y = REG_FIELD_GET(PKG_MAX_WIN_Y, r);
+ tau4 = ((1 << x_w) | x) << y;
+ max_win = mul_u64_u32_shr(tau4, SF_TIME, hwmon->scl_shift_time + x_w);
+
+ if (val > max_win)
+ return -EINVAL;
+
+ /* val in hw units */
+ val = DIV_ROUND_CLOSEST_ULL((u64)val << hwmon->scl_shift_time, SF_TIME);
+ /* Convert to 1.x * power(2,y) */
+ if (!val) {
+ /* Avoid ilog2(0) */
+ y = 0;
+ x = 0;
+ } else {
+ y = ilog2(val);
+ /* x = (val - (1 << y)) >> (y - 2); */
+ x = (val - (1ul << y)) << x_w >> y;
+ }
+
+ rxy = REG_FIELD_PREP(PKG_PWR_LIM_1_TIME_X, x) | REG_FIELD_PREP(PKG_PWR_LIM_1_TIME_Y, y);
+
+ xe_device_mem_access_get(gt_to_xe(hwmon->gt));
+
+ mutex_lock(&hwmon->hwmon_lock);
+
+ xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT, REG_RMW, (u32 *)&r,
+ PKG_PWR_LIM_1_TIME, rxy);
+
+ mutex_unlock(&hwmon->hwmon_lock);
+
+ xe_device_mem_access_put(gt_to_xe(hwmon->gt));
+
+ return count;
+}
+
+static SENSOR_DEVICE_ATTR(power1_max_interval, 0664,
+ xe_hwmon_power1_max_interval_show,
+ xe_hwmon_power1_max_interval_store, 0);
+
+static struct attribute *hwmon_attributes[] = {
+ &sensor_dev_attr_power1_max_interval.dev_attr.attr,
+ NULL
+};
+
+static umode_t xe_hwmon_attributes_visible(struct kobject *kobj,
+ struct attribute *attr, int index)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct xe_hwmon *hwmon = dev_get_drvdata(dev);
+ u32 reg_val;
+ int ret = 0;
+
+ xe_device_mem_access_get(gt_to_xe(hwmon->gt));
+
+ if (attr == &sensor_dev_attr_power1_max_interval.dev_attr.attr)
+ ret = xe_hwmon_process_reg(hwmon, REG_PKG_RAPL_LIMIT,
+ REG_READ, ®_val, 0, 0) ? 0 : attr->mode;
+
+ xe_device_mem_access_put(gt_to_xe(hwmon->gt));
+
+ return ret;
+}
+
+static const struct attribute_group hwmon_attrgroup = {
+ .attrs = hwmon_attributes,
+ .is_visible = xe_hwmon_attributes_visible,
+};
+
+static const struct attribute_group *hwmon_groups[] = {
+ &hwmon_attrgroup,
+ NULL
+};
+
static const struct hwmon_channel_info *hwmon_info[] = {
HWMON_CHANNEL_INFO(power, HWMON_P_MAX | HWMON_P_RATED_MAX | HWMON_P_CRIT),
HWMON_CHANNEL_INFO(curr, HWMON_C_CRIT),
@@ -573,6 +707,7 @@ xe_hwmon_get_preregistration_info(struct xe_device *xe)
if (!ret) {
hwmon->scl_shift_power = REG_FIELD_GET(PKG_PWR_UNIT, val_sku_unit);
hwmon->scl_shift_energy = REG_FIELD_GET(PKG_ENERGY_UNIT, val_sku_unit);
+ hwmon->scl_shift_time = REG_FIELD_GET(PKG_TIME_UNIT, val_sku_unit);
}
/*
@@ -612,7 +747,8 @@ void xe_hwmon_register(struct xe_device *xe)
"xe",
hwmon,
&hwmon_chip_info,
- NULL);
+ hwmon_groups);
+
if (IS_ERR(hwmon->hwmon_dev)) {
drm_warn(&xe->drm, "Failed to register xe hwmon (%pe)\n", hwmon->hwmon_dev);
xe->hwmon = NULL;
