drm/xe: Add frequency throttle reasons sysfs attributes

Add throttle reasons sysfs attributes under a separate directory.

/device/tile<n>/gt<n>/freq0/throttle
			|- reason_pl1
			|- reason_pl2
			|- reason_pl4
			|- reason_prochot
			|- reason_ratl
			|- reason_vr_tdc
			|- reason_vr_thermalert
			|- status

v2: Remove unnecessary headers and clean-up action (Riana)
Signed-off-by: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Reviewed-by: Riana Tauro <riana.tauro@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/xe/Makefile

@@ -78,6 +78,7 @@ xe-y += xe_bb.o \
 	xe_gt_mcr.o \
 	xe_gt_pagefault.o \
 	xe_gt_sysfs.o \
+	xe_gt_throttle_sysfs.o \
 	xe_gt_tlb_invalidation.o \
 	xe_gt_topology.o \
 	xe_guc.o \

drivers/gpu/drm/xe/regs/xe_gt_regs.h

@@ -478,4 +478,16 @@
 #define PVC_GT0_PLATFORM_ENERGY_STATUS		XE_REG(0x28106c)
 #define PVC_GT0_PACKAGE_POWER_SKU		XE_REG(0x281080)
 
+#define GT0_PERF_LIMIT_REASONS			XE_REG(0x1381a8)
+#define   GT0_PERF_LIMIT_REASONS_MASK		0xde3
+#define   PROCHOT_MASK				REG_BIT(0)
+#define   THERMAL_LIMIT_MASK			REG_BIT(1)
+#define   RATL_MASK				REG_BIT(5)
+#define   VR_THERMALERT_MASK			REG_BIT(6)
+#define   VR_TDC_MASK				REG_BIT(7)
+#define   POWER_LIMIT_4_MASK			REG_BIT(8)
+#define   POWER_LIMIT_1_MASK			REG_BIT(10)
+#define   POWER_LIMIT_2_MASK			REG_BIT(11)
+#define MTL_MEDIA_PERF_LIMIT_REASONS		XE_REG(0x138030)
+
 #endif

drivers/gpu/drm/xe/xe_gt_freq.c

@@ -13,6 +13,7 @@
 
 #include "xe_device_types.h"
 #include "xe_gt_sysfs.h"
+#include "xe_gt_throttle_sysfs.h"
 #include "xe_guc_pc.h"
 
 /**
@@ -213,4 +214,6 @@ void xe_gt_freq_init(struct xe_gt *gt)
 	if (err)
 		drm_warn(&xe->drm,  "failed to add freq attrs to %s, err: %d\n",
 			 kobject_name(gt->freq), err);
+
+	xe_gt_throttle_sysfs_init(gt);
 }

drivers/gpu/drm/xe/xe_gt_throttle_sysfs.c

+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#include <drm/drm_managed.h>
+
+#include <regs/xe_gt_regs.h>
+#include "xe_device.h"
+#include "xe_gt.h"
+#include "xe_gt_sysfs.h"
+#include "xe_gt_throttle_sysfs.h"
+#include "xe_mmio.h"
+
+/**
+ * DOC: Xe GT Throttle
+ *
+ * Provides sysfs entries for frequency throttle reasons in GT
+ *
+ * device/gt#/freq0/throttle/status - Overall status
+ * device/gt#/freq0/throttle/reason_pl1 - Frequency throttle due to PL1
+ * device/gt#/freq0/throttle/reason_pl2 - Frequency throttle due to PL2
+ * device/gt#/freq0/throttle/reason_pl4 - Frequency throttle due to PL4, Iccmax etc.
+ * device/gt#/freq0/throttle/reason_thermal - Frequency throttle due to thermal
+ * device/gt#/freq0/throttle/reason_prochot - Frequency throttle due to prochot
+ * device/gt#/freq0/throttle/reason_ratl - Frequency throttle due to RATL
+ * device/gt#/freq0/throttle/reason_vr_thermalert - Frequency throttle due to VR THERMALERT
+ * device/gt#/freq0/throttle/reason_vr_tdc -  Frequency throttle due to VR TDC
+ */
+
+static struct xe_gt *
+dev_to_gt(struct device *dev)
+{
+	return kobj_to_gt(dev->kobj.parent);
+}
+
+static u32 read_perf_limit_reasons(struct xe_gt *gt)
+{
+	u32 reg;
+
+	if (xe_gt_is_media_type(gt))
+		reg = xe_mmio_read32(gt, MTL_MEDIA_PERF_LIMIT_REASONS);
+	else
+		reg = xe_mmio_read32(gt, GT0_PERF_LIMIT_REASONS);
+
+	return reg;
+}
+
+static u32 read_status(struct xe_gt *gt)
+{
+	u32 status = read_perf_limit_reasons(gt) & GT0_PERF_LIMIT_REASONS_MASK;
+
+	return status;
+}
+
+static u32 read_reason_pl1(struct xe_gt *gt)
+{
+	u32 pl1 = read_perf_limit_reasons(gt) & POWER_LIMIT_1_MASK;
+
+	return pl1;
+}
+
+static u32 read_reason_pl2(struct xe_gt *gt)
+{
+	u32 pl2 = read_perf_limit_reasons(gt) & POWER_LIMIT_2_MASK;
+
+	return pl2;
+}
+
+static u32 read_reason_pl4(struct xe_gt *gt)
+{
+	u32 pl4 = read_perf_limit_reasons(gt) & POWER_LIMIT_4_MASK;
+
+	return pl4;
+}
+
+static u32 read_reason_thermal(struct xe_gt *gt)
+{
+	u32 thermal = read_perf_limit_reasons(gt) & THERMAL_LIMIT_MASK;
+
+	return thermal;
+}
+
+static u32 read_reason_prochot(struct xe_gt *gt)
+{
+	u32 prochot = read_perf_limit_reasons(gt) & PROCHOT_MASK;
+
+	return prochot;
+}
+
+static u32 read_reason_ratl(struct xe_gt *gt)
+{
+	u32 ratl = read_perf_limit_reasons(gt) & RATL_MASK;
+
+	return ratl;
+}
+
+static u32 read_reason_vr_thermalert(struct xe_gt *gt)
+{
+	u32 thermalert = read_perf_limit_reasons(gt) & VR_THERMALERT_MASK;
+
+	return thermalert;
+}
+
+static u32 read_reason_vr_tdc(struct xe_gt *gt)
+{
+	u32 tdc = read_perf_limit_reasons(gt) & VR_TDC_MASK;
+
+	return tdc;
+}
+
+static ssize_t status_show(struct device *dev,
+			   struct device_attribute *attr,
+			   char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool status = !!read_status(gt);
+
+	return sysfs_emit(buff, "%u\n", status);
+}
+static DEVICE_ATTR_RO(status);
+
+static ssize_t reason_pl1_show(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool pl1 = !!read_reason_pl1(gt);
+
+	return sysfs_emit(buff, "%u\n", pl1);
+}
+static DEVICE_ATTR_RO(reason_pl1);
+
+static ssize_t reason_pl2_show(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool pl2 = !!read_reason_pl2(gt);
+
+	return sysfs_emit(buff, "%u\n", pl2);
+}
+static DEVICE_ATTR_RO(reason_pl2);
+
+static ssize_t reason_pl4_show(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool pl4 = !!read_reason_pl4(gt);
+
+	return sysfs_emit(buff, "%u\n", pl4);
+}
+static DEVICE_ATTR_RO(reason_pl4);
+
+static ssize_t reason_thermal_show(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool thermal = !!read_reason_thermal(gt);
+
+	return sysfs_emit(buff, "%u\n", thermal);
+}
+static DEVICE_ATTR_RO(reason_thermal);
+
+static ssize_t reason_prochot_show(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool prochot = !!read_reason_prochot(gt);
+
+	return sysfs_emit(buff, "%u\n", prochot);
+}
+static DEVICE_ATTR_RO(reason_prochot);
+
+static ssize_t reason_ratl_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool ratl = !!read_reason_ratl(gt);
+
+	return sysfs_emit(buff, "%u\n", ratl);
+}
+static DEVICE_ATTR_RO(reason_ratl);
+
+static ssize_t reason_vr_thermalert_show(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool thermalert = !!read_reason_vr_thermalert(gt);
+
+	return sysfs_emit(buff, "%u\n", thermalert);
+}
+static DEVICE_ATTR_RO(reason_vr_thermalert);
+
+static ssize_t reason_vr_tdc_show(struct device *dev,
+				  struct device_attribute *attr,
+				  char *buff)
+{
+	struct xe_gt *gt = dev_to_gt(dev);
+	bool tdc = !!read_reason_vr_tdc(gt);
+
+	return sysfs_emit(buff, "%u\n", tdc);
+}
+static DEVICE_ATTR_RO(reason_vr_tdc);
+
+static struct attribute *throttle_attrs[] = {
+	&dev_attr_status.attr,
+	&dev_attr_reason_pl1.attr,
+	&dev_attr_reason_pl2.attr,
+	&dev_attr_reason_pl4.attr,
+	&dev_attr_reason_thermal.attr,
+	&dev_attr_reason_prochot.attr,
+	&dev_attr_reason_ratl.attr,
+	&dev_attr_reason_vr_thermalert.attr,
+	&dev_attr_reason_vr_tdc.attr,
+	NULL
+};
+
+static const struct attribute_group throttle_group_attrs = {
+	.name = "throttle",
+	.attrs = throttle_attrs,
+};
+
+static void gt_throttle_sysfs_fini(struct drm_device *drm, void *arg)
+{
+	struct xe_gt *gt = arg;
+
+	sysfs_remove_group(gt->freq, &throttle_group_attrs);
+}
+
+void xe_gt_throttle_sysfs_init(struct xe_gt *gt)
+{
+	struct xe_device *xe = gt_to_xe(gt);
+	int err;
+
+	err = sysfs_create_group(gt->freq, &throttle_group_attrs);
+	if (err) {
+		drm_warn(&xe->drm, "failed to register throttle sysfs, err: %d\n", err);
+		return;
+	}
+
+	err = drmm_add_action_or_reset(&xe->drm, gt_throttle_sysfs_fini, gt);
+	if (err)
+		drm_warn(&xe->drm, "%s: drmm_add_action_or_reset failed, err: %d\n",
+			 __func__, err);
+}

drivers/gpu/drm/xe/xe_gt_throttle_sysfs.h

+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+
+#ifndef _XE_GT_THROTTLE_SYSFS_H_
+#define _XE_GT_THROTTLE_SYSFS_H_
+
+#include <drm/drm_managed.h>
+
+struct xe_gt;
+
+void xe_gt_throttle_sysfs_init(struct xe_gt *gt);
+
+#endif /* _XE_GT_THROTTLE_SYSFS_H_ */
+