linux-kernel - [PATCH 3/6] drm/msm/dpu: don't use active in atomic

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Message-Id: <20241222-drm-dirty-modeset-v1-3-0e76a53eceb9@linaro.org>
Date: Sun, 22 Dec 2024 07:00:43 +0200
From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To: Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, 
 Maxime Ripard <mripard@...nel.org>, Thomas Zimmermann <tzimmermann@...e.de>, 
 David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>, 
 Rob Clark <robdclark@...il.com>, Abhinav Kumar <quic_abhinavk@...cinc.com>, 
 Sean Paul <sean@...rly.run>, Marijn Suijten <marijn.suijten@...ainline.org>, 
 Chandan Uddaraju <chandanu@...eaurora.org>, 
 Jeykumar Sankaran <jsanka@...eaurora.org>, 
 Jordan Crouse <jordan@...micpenguin.net>, 
 Sravanthi Kollukuduru <skolluku@...eaurora.org>
Cc: dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org, 
 Archit Taneja <architt@...eaurora.org>, 
 Rajesh Yadav <ryadav@...eaurora.org>, linux-arm-msm@...r.kernel.org, 
 freedreno@...ts.freedesktop.org, Simona Vetter <simona.vetter@...ll.ch>
Subject: [PATCH 3/6] drm/msm/dpu: don't use active in atomic_check()

The driver isn't supposed to consult crtc_state->active/active_check for
resource allocation. Instead all resources should be allocated if
crtc_state->enabled is set. Stop consulting active / active_changed in
order to determine whether the hardware resources should be
(re)allocated.

Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
Reported-by: Simona Vetter <simona.vetter@...ll.ch>
Closes: https://lore.kernel.org/dri-devel/ZtW_S0j5AEr4g0QW@phenom.ffwll.local/
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c    | 4 ----
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 3 +--
 2 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index 7191b1a6d41b3a96f956d199398f12b2923e8c82..65e33eba61726929b740831c95330756b2817e28 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -1264,10 +1264,6 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
 
 	DRM_DEBUG_ATOMIC("%s: check\n", dpu_crtc->name);
 
-	/* force a full mode set if active state changed */
-	if (crtc_state->active_changed)
-		crtc_state->mode_changed = true;
-
 	if (cstate->num_mixers) {
 		rc = _dpu_crtc_check_and_setup_lm_bounds(crtc, crtc_state);
 		if (rc)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 83de7564e2c1fe14fcf8c4f82335cafc937e1b99..d1ccdca6044353f110bf5b507788efe368f223a3 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -793,12 +793,11 @@ static int dpu_encoder_virt_atomic_check(
 		crtc_state->mode_changed = true;
 	/*
 	 * Release and Allocate resources on every modeset
-	 * Dont allocate when active is false.
 	 */
 	if (drm_atomic_crtc_needs_modeset(crtc_state)) {
 		dpu_rm_release(global_state, drm_enc);
 
-		if (!crtc_state->active_changed || crtc_state->enable)
+		if (crtc_state->enable)
 			ret = dpu_rm_reserve(&dpu_kms->rm, global_state,
 					drm_enc, crtc_state, topology);
 		if (!ret)

-- 
2.39.5