[Intel-gfx] [PATCH 12/13] drm/i915/skl: Switch to atomic watermark programming
Matt Roper
matthew.d.roper at intel.com
Thu Aug 20 18:12:03 PDT 2015
Atomic watermark programming involves pre-computing the watermark
results during the 'check' phase of an atomic transaction. Although
watermark updates are triggered by the change to a specific CRTC, the
results themselves are global, so they're stored in the
intel_atomic_state. If/when the state moves to the commit phase, the
results will be copied from the state object to dev_priv->skl_results at
the same time plane/crtc state is swapped into the various display
objects. dev_priv->wm.skl_results is a temporary staging area since actual
programming to the hardware can potentially take several vblanks
depending on the changes taking place (see skl_flush_wm_values). Once
the watermark programming has been fully flushed to the hardware, the
values will be copied to dev_priv->wm.skl_hw.
The goal here is to transition to an atomic design with minimal change
to the existing SKL WM code (which is pretty complicated). Going
forward, it probably doesn't make sense to keep triggering watermark
calculation on a CRTC-by-CRTC basis, since this can lead to us
recalculating the same results multiple times for a single transaction.
Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
---
drivers/gpu/drm/i915/intel_display.c | 1 +
drivers/gpu/drm/i915/intel_drv.h | 3 ++
drivers/gpu/drm/i915/intel_pm.c | 56 +++++++++++++++++++++++-------------
3 files changed, 40 insertions(+), 20 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index f929676..0a0e7f7 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -13192,6 +13192,7 @@ static int intel_atomic_commit(struct drm_device *dev,
drm_atomic_helper_swap_state(dev, state);
dev_priv->wm.config = to_intel_atomic_state(state)->wm_config;
+ dev_priv->wm.skl_results = to_intel_atomic_state(state)->skl_wm;
for_each_crtc_in_state(state, crtc, crtc_state, i) {
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 6a73a53..d4b2e66 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -240,6 +240,9 @@ struct intel_atomic_state {
bool dpll_set;
struct intel_shared_dpll_config shared_dpll[I915_NUM_PLLS];
struct intel_wm_config wm_config;
+
+ /* gen9-only at the moment */
+ struct skl_wm_values skl_wm;
};
struct intel_plane_state {
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index e0a4c4d..a9e9e57 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -3601,29 +3601,31 @@ static void skl_flush_wm_values(struct drm_i915_private *dev_priv,
}
}
-static bool skl_update_pipe_wm(struct drm_crtc *crtc,
+static bool skl_update_pipe_wm(struct drm_crtc_state *cstate,
struct skl_ddb_allocation *ddb, /* out */
struct skl_pipe_wm *pipe_wm /* out */)
{
- struct intel_crtc_state *cstate = to_intel_crtc_state(crtc->state);
+ struct intel_crtc_state *intel_cstate = to_intel_crtc_state(cstate);
+ struct drm_crtc *crtc = cstate->crtc;
- skl_allocate_pipe_ddb(crtc, cstate, ddb);
- skl_compute_pipe_wm(crtc, ddb, cstate, pipe_wm);
+ skl_allocate_pipe_ddb(crtc, intel_cstate, ddb);
+ skl_compute_pipe_wm(crtc, ddb, intel_cstate, pipe_wm);
- if (!memcmp(&cstate->wm.skl, pipe_wm, sizeof(*pipe_wm)))
+ if (!memcmp(&intel_cstate->wm.skl, pipe_wm, sizeof(*pipe_wm)))
return false;
- cstate->wm.skl = *pipe_wm;
+ intel_cstate->wm.skl = *pipe_wm;
return true;
}
-static void skl_update_other_pipe_wm(struct drm_device *dev,
+static void skl_update_other_pipe_wm(struct drm_atomic_state *state,
struct drm_crtc *crtc,
struct skl_wm_values *r)
{
struct intel_crtc *intel_crtc;
struct intel_crtc *this_crtc = to_intel_crtc(crtc);
+ struct drm_crtc_state *cstate;
/*
* If the WM update hasn't changed the allocation for this_crtc (the
@@ -3638,7 +3640,7 @@ static void skl_update_other_pipe_wm(struct drm_device *dev,
* Otherwise, because of this_crtc being freshly enabled/disabled, the
* other active pipes need new DDB allocation and WM values.
*/
- list_for_each_entry(intel_crtc, &dev->mode_config.crtc_list,
+ list_for_each_entry(intel_crtc, &state->dev->mode_config.crtc_list,
base.head) {
struct skl_pipe_wm pipe_wm = {};
bool wm_changed;
@@ -3646,11 +3648,13 @@ static void skl_update_other_pipe_wm(struct drm_device *dev,
if (this_crtc->pipe == intel_crtc->pipe)
continue;
- if (!intel_crtc->active)
+ cstate = drm_atomic_get_existing_crtc_state(state, &intel_crtc->base) ?:
+ intel_crtc->base.state;
+
+ if (!cstate->active)
continue;
- wm_changed = skl_update_pipe_wm(&intel_crtc->base,
- &r->ddb, &pipe_wm);
+ wm_changed = skl_update_pipe_wm(cstate, &r->ddb, &pipe_wm);
/*
* If we end up re-computing the other pipe WM values, it's
@@ -3659,28 +3663,38 @@ static void skl_update_other_pipe_wm(struct drm_device *dev,
*/
WARN_ON(!wm_changed);
- skl_compute_wm_results(dev, &pipe_wm, r, intel_crtc);
+ skl_compute_wm_results(state->dev, &pipe_wm, r, intel_crtc);
r->dirty[intel_crtc->pipe] = true;
}
}
-static void skl_update_wm(struct drm_crtc *crtc)
+static int skl_compute_wm(struct drm_crtc *crtc,
+ struct drm_atomic_state *state)
{
+ struct intel_atomic_state *intel_state = to_intel_atomic_state(state);
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
struct drm_device *dev = crtc->dev;
- struct drm_i915_private *dev_priv = dev->dev_private;
- struct skl_wm_values *results = &dev_priv->wm.skl_results;
+ struct drm_crtc_state *cstate ;
+ struct skl_wm_values *results = &intel_state->skl_wm;
struct skl_pipe_wm pipe_wm = {};
- memset(results, 0, sizeof(*results));
+ cstate = drm_atomic_get_existing_crtc_state(state, crtc) ?: crtc->state;
- if (!skl_update_pipe_wm(crtc, &results->ddb, &pipe_wm))
- return;
+ if (!skl_update_pipe_wm(cstate, &results->ddb, &pipe_wm))
+ return 0;
skl_compute_wm_results(dev, &pipe_wm, results, intel_crtc);
results->dirty[intel_crtc->pipe] = true;
- skl_update_other_pipe_wm(dev, crtc, results);
+ skl_update_other_pipe_wm(state, crtc, results);
+
+ return 0;
+}
+
+static void skl_program_watermarks(struct drm_i915_private *dev_priv)
+{
+ struct skl_wm_values *results = &dev_priv->wm.skl_results;
+
skl_write_wm_values(dev_priv, results);
skl_flush_wm_values(dev_priv, results);
@@ -3688,6 +3702,7 @@ static void skl_update_wm(struct drm_crtc *crtc)
dev_priv->wm.skl_hw = *results;
}
+
static void ilk_program_watermarks(struct drm_i915_private *dev_priv)
{
struct drm_device *dev = dev_priv->dev;
@@ -6996,7 +7011,8 @@ void intel_init_pm(struct drm_device *dev)
else if (IS_SKYLAKE(dev))
dev_priv->display.init_clock_gating =
skl_init_clock_gating;
- dev_priv->display.update_wm = skl_update_wm;
+ dev_priv->display.compute_pipe_wm = skl_compute_wm;
+ dev_priv->display.program_watermarks = skl_program_watermarks;
} else if (HAS_PCH_SPLIT(dev)) {
ilk_setup_wm_latency(dev);
--
2.1.4
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