[PATCH v7 7/7] drm/i915/gt: Add sysfs throttle frequency interfaces

Andi Shyti
2022-03-18T23:40:57Z

From: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>

Throttling here refers to the GT frequency being clipped. Each of
the throttle reason attributes will have a 0 or 1 value depending
upon whether there is throttling and also the specific reason for
it.

The following is a brief description of the sysfs throttle
frequency attributes added:

- throttle_reason_status: when set indicates that there is GT
frequency clipping.

- throttle_reason_pl1: when set indicates that PBM PL1 (platform
or package PL1) has caused GT frequency clipping.

- throttle_reason_pl2: when set indicates that PBM PL2 or PL3
(platform or package PL2 or PL3) has caused GT frequency
clipping.

- throttle_reason_pl4: when set indicates that PL4 or IccMax has
caused GT frequency clipping.

- throttle_reason_thermal: when set indicates that Thermal event
has caused GT frequency clipping.

- throttle_reason_prochot: when set indicates that PROCHOT# has
caused GT frequency clipping.

- throttle_reason_ratl: when set indicates that Running Average
Thermal Limit has caused GT frequency clipping.

- throttle_reason_vr_thermalert: when set indicates that Hot VR
(any processor VR) has caused GT frequency clipping.

- throttle_reason_vr_tdc: when set indicates that VR TDC
(Thermal Design Current) has caused GT frequency clipping.

Signed-off-by: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Dale B Stimson <dale.b.stimson@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
---
drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c | 74 +++++++++++++++++++++
drivers/gpu/drm/i915/gt/intel_rps.c | 18 +++++
drivers/gpu/drm/i915/gt/intel_rps.h | 4 ++
drivers/gpu/drm/i915/i915_reg.h | 11 +++
4 files changed, 107 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c b/drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c
index b0a1ea95d028e..26cbfa6477d12 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c
@@ -8,6 +8,7 @@
#include <linux/printk.h>

#include "i915_drv.h"
+#include "i915_reg.h"
#include "i915_sysfs.h"
#include "intel_gt.h"
#include "intel_gt_regs.h"
@@ -493,6 +494,69 @@ static DEVICE_ATTR_RO(vlv_rpe_freq_mhz);
static const struct attribute * const gen6_rps_attrs[] = GEN6_RPS_ATTR;
static const struct attribute * const gen6_gt_attrs[] = GEN6_GT_ATTR;

+static ssize_t punit_req_freq_mhz_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buff)
+{
+ struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name);
+ u32 preq = intel_rps_read_punit_req_frequency(&gt->rps);
+
+ return sysfs_emit(buff, "%u\n", preq);
+}
+
+struct intel_gt_bool_throttle_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct device *dev, struct device_attribute *attr,
+ char *buf);
+ i915_reg_t reg32;
+ u32 mask;
+};
+
+static ssize_t throttle_reason_bool_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buff)
+{
+ struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name);
+ struct intel_gt_bool_throttle_attr *t_attr =
+ (struct intel_gt_bool_throttle_attr *) attr;
+ bool val = rps_read_mask_mmio(&gt->rps, t_attr->reg32, t_attr->mask);
+
+ return sysfs_emit(buff, "%u\n", val);
+}
+
+#define INTEL_GT_RPS_BOOL_ATTR_RO(sysfs_func__, mask__) \
+struct intel_gt_bool_throttle_attr attr_##sysfs_func__ = { \
+ .attr = { .name = __stringify(sysfs_func__), .mode = 0444 }, \
+ .show = throttle_reason_bool_show, \
+ .reg32 = GT0_PERF_LIMIT_REASONS, \
+ .mask = mask__, \
+}
+
+static DEVICE_ATTR_RO(punit_req_freq_mhz);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_status, GT0_PERF_LIMIT_REASONS_MASK);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_pl1, POWER_LIMIT_1_MASK);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_pl2, POWER_LIMIT_2_MASK);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_pl4, POWER_LIMIT_4_MASK);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_thermal, THERMAL_LIMIT_MASK);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_prochot, PROCHOT_MASK);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_ratl, RATL_MASK);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_vr_thermalert, VR_THERMALERT_MASK);
+static INTEL_GT_RPS_BOOL_ATTR_RO(throttle_reason_vr_tdc, VR_TDC_MASK);
+
+static const struct attribute *freq_attrs[] = {
+ &dev_attr_punit_req_freq_mhz.attr,
+ &attr_throttle_reason_status.attr,
+ &attr_throttle_reason_pl1.attr,
+ &attr_throttle_reason_pl2.attr,
+ &attr_throttle_reason_pl4.attr,
+ &attr_throttle_reason_thermal.attr,
+ &attr_throttle_reason_prochot.attr,
+ &attr_throttle_reason_ratl.attr,
+ &attr_throttle_reason_vr_thermalert.attr,
+ &attr_throttle_reason_vr_tdc.attr,
+ NULL
+};
+
static int intel_sysfs_rps_init(struct intel_gt *gt, struct kobject *kobj,
const struct attribute * const *attrs)
{
@@ -524,4 +588,14 @@ void intel_gt_sysfs_pm_init(struct intel_gt *gt, struct kobject *kobj)
drm_warn(&gt->i915->drm,
"failed to create gt%u RPS sysfs files (%pe)",
gt->info.id, ERR_PTR(ret));
+
+ /* end of the legacy interfaces */
+ if (!is_object_gt(kobj))
+ return;
+
+ ret = sysfs_create_files(kobj, freq_attrs);
+ if (ret)
+ drm_warn(&gt->i915->drm,
+ "failed to create gt%u throttle sysfs files (%pe)",
+ gt->info.id, ERR_PTR(ret));
}
diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c
index a9c13b1a30181..6c9fdf7906c50 100644
--- a/drivers/gpu/drm/i915/gt/intel_rps.c
+++ b/drivers/gpu/drm/i915/gt/intel_rps.c
@@ -2291,6 +2291,24 @@ void intel_rps_lower_unslice(struct intel_rps *rps)
mutex_unlock(&rps->lock);
}

+static u32 rps_read_mmio(struct intel_rps *rps, i915_reg_t reg32)
+{
+ struct intel_gt *gt = rps_to_gt(rps);
+ intel_wakeref_t wakeref;
+ u32 val;
+
+ with_intel_runtime_pm(gt->uncore->rpm, wakeref)
+ val = intel_uncore_read(gt->uncore, reg32);
+
+ return val;
+}
+
+bool rps_read_mask_mmio(struct intel_rps *rps,
+ i915_reg_t reg32, u32 mask)
+{
+ return rps_read_mmio(rps, reg32) & mask;
+}
+
/* External interface for intel_ips.ko */

static struct drm_i915_private __rcu *ips_mchdev;
diff --git a/drivers/gpu/drm/i915/gt/intel_rps.h b/drivers/gpu/drm/i915/gt/intel_rps.h
index c6d76a3d13314..ba1ed9f7ecdab 100644
--- a/drivers/gpu/drm/i915/gt/intel_rps.h
+++ b/drivers/gpu/drm/i915/gt/intel_rps.h
@@ -7,6 +7,7 @@
#define INTEL_RPS_H

#include "intel_rps_types.h"
+#include "i915_reg_defs.h"

struct i915_request;

@@ -48,6 +49,9 @@ u32 intel_rps_read_state_cap(struct intel_rps *rps);
void intel_rps_raise_unslice(struct intel_rps *rps);
void intel_rps_lower_unslice(struct intel_rps *rps);

+u32 intel_rps_read_throttle_reason(struct intel_rps *rps);
+bool rps_read_mask_mmio(struct intel_rps *rps, i915_reg_t reg32, u32 mask);
+
void gen5_rps_irq_handler(struct intel_rps *rps);
void gen6_rps_irq_handler(struct intel_rps *rps, u32 pm_iir);
void gen11_rps_irq_handler(struct intel_rps *rps, u32 pm_iir);
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 2acebd5236913..a0d652f19ff93 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1837,6 +1837,17 @@
#define GEN9_RP_STATE_LIMITS _MMIO(0x138148)
#define XEHPSDV_RP_STATE_CAP _MMIO(0x250014)

+#define GT0_PERF_LIMIT_REASONS _MMIO(0x1381a8)
+#define GT0_PERF_LIMIT_REASONS_MASK 0xde3
+#define PROCHOT_MASK REG_BIT(1)
+#define THERMAL_LIMIT_MASK REG_BIT(2)
+#define RATL_MASK REG_BIT(6)
+#define VR_THERMALERT_MASK REG_BIT(7)
+#define VR_TDC_MASK REG_BIT(8)
+#define POWER_LIMIT_4_MASK REG_BIT(9)
+#define POWER_LIMIT_1_MASK REG_BIT(11)
+#define POWER_LIMIT_2_MASK REG_BIT(12)
+
#define CHV_CLK_CTL1 _MMIO(0x101100)
#define VLV_CLK_CTL2 _MMIO(0x101104)
#define CLK_CTL2_CZCOUNT_30NS_SHIFT 28
--
2.35.1