drm/i915: disable IPS while getting the pipe CRCs.

[mirror_ubuntu-artful-kernel.git] / drivers / gpu / drm / i915 / i915_debugfs.c

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 6f8c9d780632b380e45b8824d4ab4b2d569d2b36..1e7a7c68deb7f8b4fdab6fa8d4f81439726fd651 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -3255,6 +3255,8 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe,
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe];
+       struct intel_crtc *crtc = to_intel_crtc(intel_get_crtc_for_pipe(dev,
+                                                                       pipe));
        u32 val = 0; /* shut up gcc */
        int ret;
 
@@ -3290,6 +3292,14 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe,
                if (!pipe_crc->entries)
                        return -ENOMEM;
 
+               /*
+                * When IPS gets enabled, the pipe CRC changes. Since IPS gets
+                * enabled and disabled dynamically based on package C states,
+                * user space can't make reliable use of the CRCs, so let's just
+                * completely disable it.
+                */
+               hsw_disable_ips(crtc);
+
                spin_lock_irq(&pipe_crc->lock);
                pipe_crc->head = 0;
                pipe_crc->tail = 0;
@@ -3328,6 +3338,8 @@ static int pipe_crc_set_source(struct drm_device *dev, enum pipe pipe,
                        vlv_undo_pipe_scramble_reset(dev, pipe);
                else if (IS_HASWELL(dev) && pipe == PIPE_A)
                        hsw_undo_trans_edp_pipe_A_crc_wa(dev);
+
+               hsw_enable_ips(crtc);
        }
 
        return 0;