[Intel-gfx] [PATCH 3/5] drm/i915: forcewake struct mutex locking fixes

[Ben Widawsky]

Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_debugfs.c  |    5 +++++
 drivers/gpu/drm/i915/intel_display.c |    9 +++++++++
 2 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 3cb0722..30bfb2a 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -852,6 +852,7 @@ static int i915_cur_delayinfo(struct seq_file *m, void *unused)
 	struct drm_info_node *node = (struct drm_info_node *) m->private;
 	struct drm_device *dev = node->minor->dev;
 	drm_i915_private_t *dev_priv = dev->dev_private;
+	int ret;
 
 	if (IS_GEN5(dev)) {
 		u16 rgvswctl = I915_READ16(MEMSWCTL);
@@ -873,6 +874,9 @@ static int i915_cur_delayinfo(struct seq_file *m, void *unused)
 		int max_freq;
 
 		/* RPSTAT1 is in the GT power well */
+		ret = mutex_lock_interruptible(&dev->struct_mutex);
+		if (ret)
+			return ret;
 		gen6_gt_force_wake_get(dev_priv);
 
 		rpstat = I915_READ(GEN6_RPSTAT1);
@@ -919,6 +923,7 @@ static int i915_cur_delayinfo(struct seq_file *m, void *unused)
 			   max_freq * 50);
 
 		gen6_gt_force_wake_put(dev_priv);
+		mutex_unlock(&dev->struct_mutex);
 	} else {
 		seq_printf(m, "no P-state info available\n");
 	}
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index f6780cf..973aa46 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2873,7 +2873,11 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
 		ironlake_pch_enable(crtc);
 
 	intel_crtc_load_lut(crtc);
+
+	mutex_lock(&dev->struct_mutex);
 	intel_update_fbc(dev);
+	mutex_unlock(&dev->struct_mutex);
+
 	intel_crtc_update_cursor(crtc, true);
 }
 
@@ -2969,8 +2973,11 @@ static void ironlake_crtc_disable(struct drm_crtc *crtc)
 
 	intel_crtc->active = false;
 	intel_update_watermarks(dev);
+
+	mutex_lock(&dev->struct_mutex);
 	intel_update_fbc(dev);
 	intel_clear_scanline_wait(dev);
+	mutex_unlock(&dev->struct_mutex);
 }
 
 static void ironlake_crtc_dpms(struct drm_crtc *crtc, int mode)
@@ -6860,6 +6867,7 @@ void gen6_enable_rps(struct drm_i915_private *dev_priv)
 	 * userspace...
 	 */
 	I915_WRITE(GEN6_RC_STATE, 0);
+	mutex_lock(&dev_priv->dev->struct_mutex);
 	gen6_gt_force_wake_get(dev_priv);
 
 	/* disable the counters and set deterministic thresholds */
@@ -6959,6 +6967,7 @@ void gen6_enable_rps(struct drm_i915_private *dev_priv)
 	I915_WRITE(GEN6_PMINTRMSK, 0);
 
 	gen6_gt_force_wake_put(dev_priv);
+	mutex_unlock(&dev_priv->dev->struct_mutex);
 }
 
 void intel_enable_clock_gating(struct drm_device *dev)
-- 
1.7.3.4