Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux

Pull drm fixes from Dave Airlie:
 "This is a bit larger than Id like, but I asked the Intel guys to pull
  in some Skylake fixes in the possibly vain hope that Skylake might be
  more functional now that I'm seeing production hardware shipping.

  For i915, it's mostly the same patch in a few places, making sure the
  hw doesn't turn off when we are programming it.

  Apart from that are two nouveau fixes, one for a module defer bug, and
  one for using nouveau on new Lenovo P50 models.

  Then there are a bunch of AMDGPU fixes, one is a fix for v4.4 vblank
  regressions, and some PM fixes"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (26 commits)
  drm/nouveau/disp/dp: ensure sink is powered up before attempting link training
  drm/nouveau: platform: Fix deferred probe
  drm/amdgpu: disable direct VM updates when vm_debug is set
  amdgpu: fix NULL pointer dereference at tonga_check_states_equal
  drm/i915/gen9: Verify and enforce dc6 state writes
  drm/i915/gen9: Check for DC state mismatch
  drm/radeon/pm: adjust display configuration after powerstate
  drm/amdgpu/pm: adjust display configuration after powerstate
  drm/amdgpu/pm: add some checks for PX
  drm/amdgpu: fix locking in force performance level
  drm/amdgpu/gfx8: fix priv reg interrupt enable
  drm/i915/skl: Ensure HW is powered during DDB HW state readout
  drm/i915/lvds: Ensure the HW is powered during HW state readout
  drm/i915/hdmi: Ensure the HW is powered during HW state readout
  drm/i915/dsi: Ensure the HW is powered during HW state readout
  drm/i915/dp: Ensure the HW is powered during HW state readout
  drm/i915: Ensure the HW is powered when accessing the CRC HW block
  drm/i915/ddi: Ensure the HW is powered during HW state readout
  drm/i915/crt: Ensure the HW is powered during HW state readout
  drm/i915: Ensure the HW is powered during HW access in assert_pipe
  ...

1 files changed, 15 insertions, 3 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
index acd066d0a805..8297bc319369 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -72,8 +72,8 @@ static void amdgpu_flip_work_func(struct work_struct *__work)
 
 	struct drm_crtc *crtc = &amdgpuCrtc->base;
 	unsigned long flags;
-	unsigned i;
-	int vpos, hpos, stat, min_udelay;
+	unsigned i, repcnt = 4;
+	int vpos, hpos, stat, min_udelay = 0;
 	struct drm_vblank_crtc *vblank = &crtc->dev->vblank[work->crtc_id];
 
 	amdgpu_flip_wait_fence(adev, &work->excl);
@@ -96,7 +96,7 @@ static void amdgpu_flip_work_func(struct work_struct *__work)
 	 * In practice this won't execute very often unless on very fast
 	 * machines because the time window for this to happen is very small.
 	 */
-	for (;;) {
+	while (amdgpuCrtc->enabled && repcnt--) {
 		/* GET_DISTANCE_TO_VBLANKSTART returns distance to real vblank
 		 * start in hpos, and to the "fudged earlier" vblank start in
 		 * vpos.
@@ -114,10 +114,22 @@ static void amdgpu_flip_work_func(struct work_struct *__work)
 		/* Sleep at least until estimated real start of hw vblank */
 		spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
 		min_udelay = (-hpos + 1) * max(vblank->linedur_ns / 1000, 5);
+		if (min_udelay > vblank->framedur_ns / 2000) {
+			/* Don't wait ridiculously long - something is wrong */
+			repcnt = 0;
+			break;
+		}
 		usleep_range(min_udelay, 2 * min_udelay);
 		spin_lock_irqsave(&crtc->dev->event_lock, flags);
 	};
 
+	if (!repcnt)
+		DRM_DEBUG_DRIVER("Delay problem on crtc %d: min_udelay %d, "
+				 "framedur %d, linedur %d, stat %d, vpos %d, "
+				 "hpos %d\n", work->crtc_id, min_udelay,
+				 vblank->framedur_ns / 1000,
+				 vblank->linedur_ns / 1000, stat, vpos, hpos);
+
 	/* do the flip (mmio) */
 	adev->mode_info.funcs->page_flip(adev, work->crtc_id, work->base);
 	/* set the flip status */