[PATCH v2 8/8] drm/i915: add a debugfs entry for power domain info

[Imre Deak <imre.deak@intel.com>]

Add a debugfs entry showing the use-count for all power domains of each
power well.

Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 69 +++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_drv.h     |  4 +++
 drivers/gpu/drm/i915/intel_pm.c     | 16 ++++++---
 3 files changed, 85 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 6875b7a..a6555cd 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1844,6 +1844,74 @@ static int i915_pc8_status(struct seq_file *m, void *unused)
 	return 0;
 }
 
+static const char *power_domain_str(enum intel_display_power_domain domain)
+{
+#define PWRD(p)	{ POWER_DOMAIN_ ## p, # p }
+	static struct {
+		enum intel_display_power_domain domain;
+		const char *name;
+	} table[] = {
+		PWRD(PIPE_A),
+		PWRD(PIPE_B),
+		PWRD(PIPE_C),
+		PWRD(PIPE_A_PANEL_FITTER),
+		PWRD(PIPE_B_PANEL_FITTER),
+		PWRD(PIPE_C_PANEL_FITTER),
+		PWRD(TRANSCODER_A),
+		PWRD(TRANSCODER_B),
+		PWRD(TRANSCODER_C),
+		PWRD(TRANSCODER_EDP),
+		PWRD(VGA),
+		PWRD(AUDIO),
+		PWRD(INIT),
+	};
+#undef PWRD
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(table); i++)
+		if (table[i].domain == domain)
+			return table[i].name;
+
+	WARN_ON(1);
+
+	return "?";
+}
+
+static int i915_power_domain_info(struct seq_file *m, void *unused)
+{
+	struct drm_info_node *node = (struct drm_info_node *) m->private;
+	struct drm_device *dev = node->minor->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct i915_power_domains *power_domains = &dev_priv->power_domains;
+	int i;
+
+	mutex_lock(&power_domains->lock);
+
+	seq_printf(m, "%-25s %s\n", "Power well/domain", "Use count");
+	for (i = 0; i < power_domains->power_well_count; i++) {
+		struct i915_power_well *power_well;
+		enum intel_display_power_domain power_domain;
+
+		power_well = &power_domains->power_wells[i];
+		seq_printf(m, "%-25s %d\n", power_well->name,
+			   power_well->count);
+
+		for (power_domain = 0; power_domain < POWER_DOMAIN_NUM;
+		     power_domain++) {
+			if (!(BIT(power_domain) & power_well->domains))
+				continue;
+
+			seq_printf(m, "  %-23s %d\n",
+				   power_domain_str(power_domain),
+				   power_well->domain_count[power_domain]);
+		}
+	}
+
+	mutex_unlock(&power_domains->lock);
+
+	return 0;
+}
+
 struct pipe_crc_info {
 	const char *name;
 	struct drm_device *dev;
@@ -3076,6 +3144,7 @@ static const struct drm_info_list i915_debugfs_list[] = {
 	{"i915_edp_psr_status", i915_edp_psr_status, 0},
 	{"i915_energy_uJ", i915_energy_uJ, 0},
 	{"i915_pc8_status", i915_pc8_status, 0},
+	{"i915_power_domain_info", i915_power_domain_info, 0},
 };
 #define I915_DEBUGFS_ENTRIES ARRAY_SIZE(i915_debugfs_list)
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 06f47bf..194e39f 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -950,6 +950,10 @@ struct i915_power_well {
 	/* power well enable/disable usage count */
 	int count;
 	unsigned long domains;
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	/* usage count for each power domain in the domains mask */
+	int domain_count[POWER_DOMAIN_NUM];
+#endif
 	void *data;
 	void (*set)(struct drm_device *dev, struct i915_power_well *power_well,
 		    bool enable);
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index d252453..99210c1 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -5726,17 +5726,25 @@ static void hsw_set_power_well(struct drm_device *dev,
 }
 
 static void __intel_power_well_get(struct drm_device *dev,
-				   struct i915_power_well *power_well)
+				   struct i915_power_well *power_well,
+				   enum intel_display_power_domain domain)
 {
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	power_well->domain_count[domain]++;
+#endif
 	if (!power_well->count++ && power_well->set)
 		power_well->set(dev, power_well, true);
 }
 
 static void __intel_power_well_put(struct drm_device *dev,
-				   struct i915_power_well *power_well)
+				   struct i915_power_well *power_well,
+				   enum intel_display_power_domain domain)
 {
 	WARN_ON(!power_well->count);
 
+#if IS_ENABLED(CONFIG_DEBUG_FS)
+	power_well->domain_count[domain]--;
+#endif
 	if (!--power_well->count && power_well->set && i915_disable_power_well)
 		power_well->set(dev, power_well, false);
 }
@@ -5753,7 +5761,7 @@ void intel_display_power_get(struct drm_device *dev,
 
 	mutex_lock(&power_domains->lock);
 	for_each_power_well(i, power_well, BIT(domain), power_domains)
-		__intel_power_well_get(dev, power_well);
+		__intel_power_well_get(dev, power_well, domain);
 	mutex_unlock(&power_domains->lock);
 }
 
@@ -5769,7 +5777,7 @@ void intel_display_power_put(struct drm_device *dev,
 
 	mutex_lock(&power_domains->lock);
 	for_each_power_well_rev(i, power_well, BIT(domain), power_domains)
-		__intel_power_well_put(dev, power_well);
+		__intel_power_well_put(dev, power_well, domain);
 	mutex_unlock(&power_domains->lock);
 }
 
-- 
1.8.4