* [PATCH 1/2] drm/bridge: analogix_dp: Support PSR-exit to disable transition
[not found] <20220215235420.1284208-1-briannorris@chromium.org>
@ 2022-02-15 23:54 ` Brian Norris
2022-02-15 23:54 ` [PATCH 2/2] drm/atomic: Force bridge self-refresh-exit on CRTC switch Brian Norris
1 sibling, 0 replies; 4+ messages in thread
From: Brian Norris @ 2022-02-15 23:54 UTC (permalink / raw)
To: Andrzej Hajda, Neil Armstrong, Robert Foss, David Airlie,
Daniel Vetter, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann
Cc: Heiko Stuebner, Jernej Skrabec, dri-devel, Laurent Pinchart,
Jonas Karlman, Sean Paul, linux-kernel, Sean Paul, Brian Norris,
stable
Most eDP panel functions only work correctly when the panel is not in
self-refresh. In particular, analogix_dp_bridge_disable() tends to hit
AUX channel errors if the panel is in self-refresh.
Given the above, it appears that so far, this driver assumes that we are
never in self-refresh when it comes time to fully disable the bridge.
Prior to commit 846c7dfc1193 ("drm/atomic: Try to preserve the crtc
enabled state in drm_atomic_remove_fb, v2."), this tended to be true,
because we would automatically disable the pipe when framebuffers were
removed, and so we'd typically disable the bridge shortly after the last
display activity.
However, that is not guaranteed: an idle (self-refresh) display pipe may
be disabled, e.g., when switching CRTCs. We need to exit PSR first.
Stable notes: this is definitely a bugfix, and the bug has likely
existed in some form for quite a while. It may predate the "PSR helpers"
refactor, but the code looked very different before that, and it's
probably not worth rewriting the fix.
Cc: <stable@vger.kernel.org>
Fixes: 6c836d965bad ("drm/rockchip: Use the helpers for PSR")
Signed-off-by: Brian Norris <briannorris@chromium.org>
---
.../drm/bridge/analogix/analogix_dp_core.c | 42 +++++++++++++++++--
1 file changed, 38 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index b7d2e4449cfa..6ee0f62a7161 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -1268,6 +1268,25 @@ static int analogix_dp_bridge_attach(struct drm_bridge *bridge,
return 0;
}
+static
+struct drm_crtc *analogix_dp_get_old_crtc(struct analogix_dp_device *dp,
+ struct drm_atomic_state *state)
+{
+ struct drm_encoder *encoder = dp->encoder;
+ struct drm_connector *connector;
+ struct drm_connector_state *conn_state;
+
+ connector = drm_atomic_get_old_connector_for_encoder(state, encoder);
+ if (!connector)
+ return NULL;
+
+ conn_state = drm_atomic_get_old_connector_state(state, connector);
+ if (!conn_state)
+ return NULL;
+
+ return conn_state->crtc;
+}
+
static
struct drm_crtc *analogix_dp_get_new_crtc(struct analogix_dp_device *dp,
struct drm_atomic_state *state)
@@ -1448,14 +1467,16 @@ analogix_dp_bridge_atomic_disable(struct drm_bridge *bridge,
{
struct drm_atomic_state *old_state = old_bridge_state->base.state;
struct analogix_dp_device *dp = bridge->driver_private;
- struct drm_crtc *crtc;
+ struct drm_crtc *old_crtc, *new_crtc;
+ struct drm_crtc_state *old_crtc_state = NULL;
struct drm_crtc_state *new_crtc_state = NULL;
+ int ret;
- crtc = analogix_dp_get_new_crtc(dp, old_state);
- if (!crtc)
+ new_crtc = analogix_dp_get_new_crtc(dp, old_state);
+ if (!new_crtc)
goto out;
- new_crtc_state = drm_atomic_get_new_crtc_state(old_state, crtc);
+ new_crtc_state = drm_atomic_get_new_crtc_state(old_state, new_crtc);
if (!new_crtc_state)
goto out;
@@ -1464,6 +1485,19 @@ analogix_dp_bridge_atomic_disable(struct drm_bridge *bridge,
return;
out:
+ old_crtc = analogix_dp_get_old_crtc(dp, old_state);
+ if (old_crtc) {
+ old_crtc_state = drm_atomic_get_old_crtc_state(old_state,
+ old_crtc);
+
+ /* When moving from PSR to fully disabled, exit PSR first. */
+ if (old_crtc_state && old_crtc_state->self_refresh_active) {
+ ret = analogix_dp_disable_psr(dp);
+ if (ret)
+ DRM_ERROR("Failed to disable psr (%d)\n", ret);
+ }
+ }
+
analogix_dp_bridge_disable(bridge);
}
--
2.35.1.265.g69c8d7142f-goog
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 2/2] drm/atomic: Force bridge self-refresh-exit on CRTC switch
[not found] <20220215235420.1284208-1-briannorris@chromium.org>
2022-02-15 23:54 ` [PATCH 1/2] drm/bridge: analogix_dp: Support PSR-exit to disable transition Brian Norris
@ 2022-02-15 23:54 ` Brian Norris
2022-02-28 9:02 ` Liu Ying
1 sibling, 1 reply; 4+ messages in thread
From: Brian Norris @ 2022-02-15 23:54 UTC (permalink / raw)
To: Andrzej Hajda, Neil Armstrong, Robert Foss, David Airlie,
Daniel Vetter, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann
Cc: Heiko Stuebner, Jernej Skrabec, dri-devel, Laurent Pinchart,
Jonas Karlman, Sean Paul, linux-kernel, Sean Paul, Brian Norris,
stable
It's possible to change which CRTC is in use for a given
connector/encoder/bridge while we're in self-refresh without fully
disabling the connector/encoder/bridge along the way. This can confuse
the bridge encoder/bridge, because
(a) it needs to track the SR state (trying to perform "active"
operations while the panel is still in SR can be Bad(TM)); and
(b) it tracks the SR state via the CRTC state (and after the switch, the
previous SR state is lost).
Thus, we need to either somehow carry the self-refresh state over to the
new CRTC, or else force an encoder/bridge self-refresh transition during
such a switch.
I choose the latter, so we disable the encoder (and exit PSR) before
attaching it to the new CRTC (where we can continue to assume a clean
(non-self-refresh) state).
This fixes PSR issues seen on Rockchip RK3399 systems with
drivers/gpu/drm/bridge/analogix/analogix_dp_core.c.
Cc: <stable@vger.kernel.org>
Fixes: 1452c25b0e60 ("drm: Add helpers to kick off self refresh mode in drivers")
Signed-off-by: Brian Norris <briannorris@chromium.org>
---
drivers/gpu/drm/drm_atomic_helper.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 9603193d2fa1..74161d007894 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1011,9 +1011,19 @@ crtc_needs_disable(struct drm_crtc_state *old_state,
return drm_atomic_crtc_effectively_active(old_state);
/*
- * We need to run through the crtc_funcs->disable() function if the CRTC
- * is currently on, if it's transitioning to self refresh mode, or if
- * it's in self refresh mode and needs to be fully disabled.
+ * We need to disable bridge(s) and CRTC if we're transitioning out of
+ * self-refresh and changing CRTCs at the same time, because the
+ * bridge tracks self-refresh status via CRTC state.
+ */
+ if (old_state->self_refresh_active && new_state->enable &&
+ old_state->crtc != new_state->crtc)
+ return true;
+
+ /*
+ * We also need to run through the crtc_funcs->disable() function if
+ * the CRTC is currently on, if it's transitioning to self refresh
+ * mode, or if it's in self refresh mode and needs to be fully
+ * disabled.
*/
return old_state->active ||
(old_state->self_refresh_active && !new_state->active) ||
--
2.35.1.265.g69c8d7142f-goog
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