[PATCH 3/5] drm/i915: Fix watermarks for VLV/CHV

ville.syrjala
2016-03-09T17:07:25Z

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

commit 92826fcdfc14 ("drm/i915: Calculate watermark related members in the crtc_state, v4.")
broke thigns by removing the pre vs. post wm update distinction. We also
lost the pre plane wm update entirely for VLV/CHV from the crtc enable
path.

This caused underruns on modeset and plane enable/disable on CHV,
and often those can lead to a dead pipe.

So let's bring back the pre vs. post thing, and let's toss in an
explicit wm update to valleyview_crtc_enable() to avoid having to
put it into the common code.

This is more or less a partial revert of the offending commit.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Fixes: 92826fcdfc14 ("drm/i915: Calculate watermark related members in the crtc_state, v4.")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
drivers/gpu/drm/i915/intel_atomic.c | 3 ++-
drivers/gpu/drm/i915/intel_display.c | 29 +++++++++++++++++++----------
drivers/gpu/drm/i915/intel_drv.h | 2 +-
3 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_atomic.c b/drivers/gpu/drm/i915/intel_atomic.c
index 6a661e796328..79448f1c8b8d 100644
--- a/drivers/gpu/drm/i915/intel_atomic.c
+++ b/drivers/gpu/drm/i915/intel_atomic.c
@@ -96,7 +96,8 @@ intel_crtc_duplicate_state(struct drm_crtc *crtc)
crtc_state->update_pipe = false;
crtc_state->disable_lp_wm = false;
crtc_state->disable_cxsr = false;
- crtc_state->wm_changed = false;
+ crtc_state->update_wm_pre = false;
+ crtc_state->update_wm_post = false;
crtc_state->fb_changed = false;
crtc_state->wm.need_postvbl_update = false;

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 62d36a7b3398..8b44e0652740 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4919,7 +4919,7 @@ static void intel_post_plane_update(struct intel_crtc *crtc)

crtc->wm.cxsr_allowed = true;

- if (pipe_config->wm_changed && pipe_config->base.active)
+ if (pipe_config->update_wm_post && pipe_config->base.active)
intel_update_watermarks(&crtc->base);

if (atomic->update_fbc)
@@ -5001,7 +5001,7 @@ static void intel_pre_plane_update(struct intel_crtc_state *old_crtc_state)
*/
if (dev_priv->display.initial_watermarks != NULL)
dev_priv->display.initial_watermarks(pipe_config);
- else if (pipe_config->wm_changed)
+ else if (pipe_config->update_wm_pre)
intel_update_watermarks(&crtc->base);
}

@@ -6372,6 +6372,7 @@ static void valleyview_crtc_enable(struct drm_crtc *crtc)

intel_crtc_load_lut(crtc);

+ intel_update_watermarks(crtc);
intel_enable_pipe(intel_crtc);

assert_vblank_disabled(crtc);
@@ -11994,19 +11995,27 @@ int intel_plane_atomic_calc_changes(struct drm_crtc_state *crtc_state,
plane->base.id, was_visible, visible,
turn_off, turn_on, mode_changed);

- if (turn_on || turn_off) {
- pipe_config->wm_changed = true;
+ if (turn_on) {
+ pipe_config->update_wm_pre = true;
+
+ /* must disable cxsr around plane enable/disable */
+ if (plane->type != DRM_PLANE_TYPE_CURSOR)
+ pipe_config->disable_cxsr = true;
+ } else if (turn_off) {
+ pipe_config->update_wm_post = true;

/* must disable cxsr around plane enable/disable */
if (plane->type != DRM_PLANE_TYPE_CURSOR)
pipe_config->disable_cxsr = true;
} else if (intel_wm_need_update(plane, plane_state)) {
- pipe_config->wm_changed = true;
+ /* FIXME bollocks */
+ pipe_config->update_wm_pre = true;
+ pipe_config->update_wm_post = true;
}

/* Pre-gen9 platforms need two-step watermark updates */
- if (pipe_config->wm_changed && INTEL_INFO(dev)->gen < 9 &&
- dev_priv->display.optimize_watermarks)
+ if ((pipe_config->update_wm_pre || pipe_config->update_wm_post) &&
+ INTEL_INFO(dev)->gen < 9 && dev_priv->display.optimize_watermarks)
to_intel_crtc_state(crtc_state)->wm.need_postvbl_update = true;

if (visible || was_visible)
@@ -12106,7 +12115,7 @@ static int intel_crtc_atomic_check(struct drm_crtc *crtc,
}

if (mode_changed && !crtc_state->active)
- pipe_config->wm_changed = true;
+ pipe_config->update_wm_post = true;

if (mode_changed && crtc_state->enable &&
dev_priv->display.crtc_compute_clock &&
@@ -13645,12 +13654,12 @@ static bool needs_vblank_wait(struct intel_crtc_state *crtc_state)
return true;

/* wm changes, need vblank before final wm's */
- if (crtc_state->wm_changed)
+ if (crtc_state->update_wm_post)
return true;

/*
* cxsr is re-enabled after vblank.
- * This is already handled by crtc_state->wm_changed,
+ * This is already handled by crtc_state->update_wm_post,
* but added for clarity.
*/
if (crtc_state->disable_cxsr)
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 7b2d66d8dd7f..c33e9690df51 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -420,7 +420,7 @@ struct intel_crtc_state {

bool update_pipe; /* can a fast modeset be performed? */
bool disable_cxsr;
- bool wm_changed; /* watermarks are updated */
+ bool update_wm_pre, update_wm_post; /* watermarks are updated */
bool fb_changed; /* fb on any of the planes is changed */

/* Pipe source size (ie. panel fitter input size)
--
2.4.10