[Intel-gfx] [PATCH] drm/i915: Debugfs disable RPS boost and idle

[Daisy Sun]

RP frequency request is affected by 2 modules: normal turbo
algorithm and RPS boost algorithm. By adding RPS boost algorithm
to the mix, the final frequency becomes relatively unpredictable.
Add a switch to enable/disable RPS boost functionality. When
disabled, RP frequency will follow the normal turbo algorithm only

Issue: VIZ-3801
Signed-off-by: Daisy Sun <daisy.sun at intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 40 +++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_drv.h     |  1 +
 drivers/gpu/drm/i915/intel_pm.c     |  8 ++++++--
 3 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 1e83ae4..2077bbd 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -3486,6 +3486,45 @@ DEFINE_SIMPLE_ATTRIBUTE(i915_drop_caches_fops,
 			i915_drop_caches_get, i915_drop_caches_set,
 			"0x%08llx\n");
 
+static int i915_rps_disable_boost_get(void *data, u64 *val)
+{
+	struct drm_device *dev = data;
+	drm_i915_private *dev_priv = dev->dev_private;
+
+	if (INTEL_INFO(dev)->gen < 6)
+		return -ENODEV;
+
+	*val = dev_priv->rps.debugfs_disable_boost;
+
+	return 0;
+}
+
+static int i915_rps_disable_boost_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	drm_i915_private *dev_priv = dev->dev_private;
+	int ret;
+
+	flush_delayed_work(&dev_priv->rps.delayed_resume_work);
+
+	DRM_DEBUG_DRIVER("Setting RPS disable Boost-Idle mode to %s\n",
+				 val ? "on" : "off");
+
+	ret = mutex_lock_interruptible(&dev_priv->rps.hw_lock);
+	if (ret)
+		return ret;
+
+	dev_priv->rps.debugfs_disable_boost = val;
+
+	mutex_unlock(&dev_priv->rps.hw_lock);
+
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_rps_disable_boost_fops,
+		i915_rps_disable_boost_get, i915_rps_disable_boost_set,
+			"%llu\n");
+
 static int
 i915_max_freq_get(void *data, u64 *val)
 {
@@ -3821,6 +3860,7 @@ static const struct i915_debugfs_files {
 	{"i915_wedged", &i915_wedged_fops},
 	{"i915_max_freq", &i915_max_freq_fops},
 	{"i915_min_freq", &i915_min_freq_fops},
+	{"i915_rps_disable_boost", &i915_rps_disable_boost_fops},
 	{"i915_cache_sharing", &i915_cache_sharing_fops},
 	{"i915_ring_stop", &i915_ring_stop_fops},
 	{"i915_ring_missed_irq", &i915_ring_missed_irq_fops},
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 272aa7a..9c427da 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -847,6 +847,7 @@ struct intel_gen6_power_mgmt {
 	int last_adj;
 	enum { LOW_POWER, BETWEEN, HIGH_POWER } power;
 
+	bool debugfs_disable_boost;
 	bool enabled;
 	struct delayed_work delayed_resume_work;
 
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 75c1c76..6acac14 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -3163,7 +3163,9 @@ void gen6_rps_idle(struct drm_i915_private *dev_priv)
 	struct drm_device *dev = dev_priv->dev;
 
 	mutex_lock(&dev_priv->rps.hw_lock);
-	if (dev_priv->rps.enabled) {
+
+	if (dev_priv->rps.enabled
+		&& !dev_priv->rps.debugfs_disable_boost) {
 		if (IS_VALLEYVIEW(dev))
 			vlv_set_rps_idle(dev_priv);
 		else
@@ -3178,7 +3180,9 @@ void gen6_rps_boost(struct drm_i915_private *dev_priv)
 	struct drm_device *dev = dev_priv->dev;
 
 	mutex_lock(&dev_priv->rps.hw_lock);
-	if (dev_priv->rps.enabled) {
+
+	if (dev_priv->rps.enabled
+		&& !dev_priv->rps.debugfs_disable_boost) {
 		if (IS_VALLEYVIEW(dev))
 			valleyview_set_rps(dev_priv->dev, dev_priv->rps.max_freq_softlimit);
 		else
-- 
1.9.1