drm/i915/gt: Expose per-gt RPS defaults in sysfs

Add the following sysfs files to gt/gtN/.defaults/:
* rps_min_freq_mhz
* rps_max_freq_mhz

v2: Correct gt/gtN/.defaults/* file names in commit message
v3: Remove rps_boost_freq_mhz since it is not consumed by userspace

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/cf6e483bf79f871c2c8c74af6005bf6a83a3a1ce.1658192398.git.ashutosh.dixit@intel.com

drivers/gpu/drm/i915/gt/intel_gt_sysfs.c

@@ -22,11 +22,6 @@ bool is_object_gt(struct kobject *kobj)
 	return !strncmp(kobj->name, "gt", 2);
 }
 
-static struct intel_gt *kobj_to_gt(struct kobject *kobj)
-{
-	return container_of(kobj, struct intel_gt, sysfs_gt);
-}
-
 struct intel_gt *intel_gt_sysfs_get_drvdata(struct device *dev,
 					    const char *name)
 {

drivers/gpu/drm/i915/gt/intel_gt_sysfs.h

@@ -10,6 +10,7 @@
 #include <linux/kobject.h>
 
 #include "i915_gem.h" /* GEM_BUG_ON() */
+#include "intel_gt_types.h"
 
 struct intel_gt;
 
@@ -22,6 +23,11 @@ intel_gt_create_kobj(struct intel_gt *gt,
 		     struct kobject *dir,
 		     const char *name);
 
+static inline struct intel_gt *kobj_to_gt(struct kobject *kobj)
+{
+	return container_of(kobj, struct intel_gt, sysfs_gt);
+}
+
 void intel_gt_sysfs_register(struct intel_gt *gt);
 void intel_gt_sysfs_unregister(struct intel_gt *gt);
 struct intel_gt *intel_gt_sysfs_get_drvdata(struct device *dev,

drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c

@@ -727,6 +727,34 @@ static const struct attribute *media_perf_power_attrs[] = {
 	NULL
 };
 
+static ssize_t
+default_min_freq_mhz_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	struct intel_gt *gt = kobj_to_gt(kobj->parent);
+
+	return sysfs_emit(buf, "%u\n", gt->defaults.min_freq);
+}
+
+static struct kobj_attribute default_min_freq_mhz =
+__ATTR(rps_min_freq_mhz, 0444, default_min_freq_mhz_show, NULL);
+
+static ssize_t
+default_max_freq_mhz_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+	struct intel_gt *gt = kobj_to_gt(kobj->parent);
+
+	return sysfs_emit(buf, "%u\n", gt->defaults.max_freq);
+}
+
+static struct kobj_attribute default_max_freq_mhz =
+__ATTR(rps_max_freq_mhz, 0444, default_max_freq_mhz_show, NULL);
+
+static const struct attribute * const rps_defaults_attrs[] = {
+	&default_min_freq_mhz.attr,
+	&default_max_freq_mhz.attr,
+	NULL
+};
+
 static int intel_sysfs_rps_init(struct intel_gt *gt, struct kobject *kobj,
 				const struct attribute * const *attrs)
 {
@@ -776,4 +804,10 @@ void intel_gt_sysfs_pm_init(struct intel_gt *gt, struct kobject *kobj)
 				 "failed to create gt%u media_perf_power_attrs sysfs (%pe)\n",
 				 gt->info.id, ERR_PTR(ret));
 	}
+
+	ret = sysfs_create_files(gt->sysfs_defaults, rps_defaults_attrs);
+	if (ret)
+		drm_warn(&gt->i915->drm,
+			 "failed to add gt%u rps defaults (%pe)\n",
+			 gt->info.id, ERR_PTR(ret));
 }

drivers/gpu/drm/i915/gt/intel_gt_types.h

@@ -76,6 +76,8 @@ enum intel_submission_method {
 };
 
 struct gt_defaults {
+	u32 min_freq;
+	u32 max_freq;
 };
 
 struct intel_gt {

drivers/gpu/drm/i915/gt/intel_rps.c

@@ -1979,7 +1979,9 @@ void intel_rps_init(struct intel_rps *rps)
 
 	/* Derive initial user preferences/limits from the hardware limits */
 	rps->max_freq_softlimit = rps->max_freq;
+	rps_to_gt(rps)->defaults.max_freq = rps->max_freq_softlimit;
 	rps->min_freq_softlimit = rps->min_freq;
+	rps_to_gt(rps)->defaults.min_freq = rps->min_freq_softlimit;
 
 	/* After setting max-softlimit, find the overclock max freq */
 	if (GRAPHICS_VER(i915) == 6 || IS_IVYBRIDGE(i915) || IS_HASWELL(i915)) {

drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c

@@ -575,20 +575,24 @@ static int slpc_set_softlimits(struct intel_guc_slpc *slpc)
 	 * unless they have deviated from defaults, in which case,
 	 * we retain the values and set min/max accordingly.
 	 */
-	if (!slpc->max_freq_softlimit)
+	if (!slpc->max_freq_softlimit) {
 		slpc->max_freq_softlimit = slpc->rp0_freq;
-	else if (slpc->max_freq_softlimit != slpc->rp0_freq)
+		slpc_to_gt(slpc)->defaults.max_freq = slpc->max_freq_softlimit;
+	} else if (slpc->max_freq_softlimit != slpc->rp0_freq) {
 		ret = intel_guc_slpc_set_max_freq(slpc,
 						  slpc->max_freq_softlimit);
+	}
 
 	if (unlikely(ret))
 		return ret;
 
-	if (!slpc->min_freq_softlimit)
+	if (!slpc->min_freq_softlimit) {
 		slpc->min_freq_softlimit = slpc->min_freq;
-	else if (slpc->min_freq_softlimit != slpc->min_freq)
+		slpc_to_gt(slpc)->defaults.min_freq = slpc->min_freq_softlimit;
+	} else if (slpc->min_freq_softlimit != slpc->min_freq) {
 		return intel_guc_slpc_set_min_freq(slpc,
 						   slpc->min_freq_softlimit);
+	}
 
 	return 0;
 }