[PATCH v1.1 1/2] drm/i915: Allow preservation of watermarks, v2.

Maarten Lankhorst
2016-03-02T11:38:17Z

As Paulo has noted we can help bisectability by separating computing
watermarks on a noop in 2 separate commits.

This patch no longer clears the crtc watermark state, but recalculates
it completely. Regardless whether a level is used the full values for
each level are calculated. If a level is invalid wm[level].enable is
unset.

Changes since v1:
- Only call ilk_validate_wm_level when level <= usable_level.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
---
drivers/gpu/drm/i915/intel_pm.c | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 61dcac9dea37..4c21b98e5a5c 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2300,7 +2300,7 @@ static int ilk_compute_pipe_wm(struct intel_crtc *intel_crtc,
struct intel_plane_state *pristate = NULL;
struct intel_plane_state *sprstate = NULL;
struct intel_plane_state *curstate = NULL;
- int level, max_level = ilk_wm_max_level(dev);
+ int level, max_level = ilk_wm_max_level(dev), usable_level;
struct ilk_wm_maximums max;

cstate = intel_atomic_get_crtc_state(state, intel_crtc);
@@ -2308,7 +2308,6 @@ static int ilk_compute_pipe_wm(struct intel_crtc *intel_crtc,
return PTR_ERR(cstate);

pipe_wm = &cstate->wm.optimal.ilk;
- memset(pipe_wm, 0, sizeof(*pipe_wm));

for_each_intel_plane_on_crtc(dev, intel_crtc, intel_plane) {
ps = drm_atomic_get_plane_state(state,
@@ -2330,13 +2329,15 @@ static int ilk_compute_pipe_wm(struct intel_crtc *intel_crtc,
(drm_rect_width(&sprstate->dst) != drm_rect_width(&sprstate->src) >> 16 ||
drm_rect_height(&sprstate->dst) != drm_rect_height(&sprstate->src) >> 16);

+ usable_level = max_level;
+
/* ILK/SNB: LP2+ watermarks only w/o sprites */
if (INTEL_INFO(dev)->gen <= 6 && sprstate->visible)
- max_level = 1;
+ usable_level = 1;

/* ILK/SNB/IVB: LP1+ watermarks only w/o scaling */
if (pipe_wm->sprites_scaled)
- max_level = 0;
+ usable_level = 0;

ilk_compute_wm_level(dev_priv, intel_crtc, 0, cstate,
pristate, sprstate, curstate, &pipe_wm->wm[0]);
@@ -2350,20 +2351,22 @@ static int ilk_compute_pipe_wm(struct intel_crtc *intel_crtc,
ilk_compute_wm_reg_maximums(dev, 1, &max);

for (level = 1; level <= max_level; level++) {
- struct intel_wm_level wm = {};
+ struct intel_wm_level *wm = &pipe_wm->wm[level];

ilk_compute_wm_level(dev_priv, intel_crtc, level, cstate,
- pristate, sprstate, curstate, &wm);
+ pristate, sprstate, curstate, wm);

/*
* Disable any watermark level that exceeds the
* register maximums since such watermarks are
* always invalid.
*/
- if (!ilk_validate_wm_level(level, &max, &wm))
- break;
-
- pipe_wm->wm[level] = wm;
+ if (level > usable_level) {
+ wm->enable = false;
+ } else if (!ilk_validate_wm_level(level, &max, wm)) {
+ wm->enable = false;
+ usable_level = level;
+ }
}

return 0;
--
2.1.0