[PATCH v3 4/4] drm/msm/dpu: reserve the resources on topology change

[Kalyan Thota]

Some features like CTM can be enabled dynamically. Release
and reserve the DPU resources whenever a topology change
occurs such that required hw blocks are allocated appropriately.

Signed-off-by: Kalyan Thota <quic_kalyant at quicinc.com>
---
Changes in v1:
- Avoid mode_set call directly (Dmitry)

Changes in v2:
- Minor nits (Dmitry)

Changes in v3:
- avoid unnecessary modeset check call (Dmitry)
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h    |  2 ++
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 24 +++++++++++++++++++-----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
index 539b68b..85bd5645 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
@@ -204,6 +204,7 @@ struct dpu_crtc {
  * @hw_ctls       : List of active ctl paths
  * @crc_source    : CRC source
  * @crc_frame_skip_count: Number of frames skipped before getting CRC
+ * @ctm_enabled   : Cached color management enablement state
  */
 struct dpu_crtc_state {
 	struct drm_crtc_state base;
@@ -225,6 +226,7 @@ struct dpu_crtc_state {
 
 	enum dpu_crtc_crc_source crc_source;
 	int crc_frame_skip_count;
+	bool ctm_enabled;
 };
 
 #define to_dpu_crtc_state(x) \
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index 3920efd..038e077 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -217,6 +217,19 @@ static u32 dither_matrix[DITHER_MATRIX_SZ] = {
 	15, 7, 13, 5, 3, 11, 1, 9, 12, 4, 14, 6, 0, 8, 2, 10
 };
 
+static bool _dpu_enc_is_dspp_changed(struct drm_crtc_state *crtc_state,
+	struct msm_display_topology topology)
+{
+	struct dpu_crtc_state *cstate = to_dpu_crtc_state(crtc_state);
+
+	if ((cstate->ctm_enabled && !topology.num_dspp) ||
+	    (!cstate->ctm_enabled && topology.num_dspp)) {
+		crtc_state->mode_changed = true;
+		return true;
+	}
+
+	return false;
+}
 
 bool dpu_encoder_is_widebus_enabled(const struct drm_encoder *drm_enc)
 {
@@ -642,14 +655,15 @@ static int dpu_encoder_virt_atomic_check(
 
 	topology = dpu_encoder_get_topology(dpu_enc, dpu_kms, adj_mode, crtc_state);
 
+	_dpu_enc_is_dspp_changed(crtc_state, topology);
+
 	/*
 	 * 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->active)
+		if (crtc_state->enable)
 			ret = dpu_rm_reserve(&dpu_kms->rm, global_state,
 					drm_enc, crtc_state, topology);
 	}
@@ -1022,7 +1036,7 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 	struct dpu_hw_blk *hw_lm[MAX_CHANNELS_PER_ENC];
 	struct dpu_hw_blk *hw_dspp[MAX_CHANNELS_PER_ENC] = { NULL };
 	struct dpu_hw_blk *hw_dsc[MAX_CHANNELS_PER_ENC];
-	int num_lm, num_ctl, num_pp, num_dsc;
+	int num_lm, num_ctl, num_pp, num_dsc, num_dspp;
 	unsigned int dsc_mask = 0;
 	int i;
 
@@ -1053,7 +1067,7 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 		drm_enc->base.id, DPU_HW_BLK_CTL, hw_ctl, ARRAY_SIZE(hw_ctl));
 	num_lm = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
 		drm_enc->base.id, DPU_HW_BLK_LM, hw_lm, ARRAY_SIZE(hw_lm));
-	dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
+	num_dspp = dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
 		drm_enc->base.id, DPU_HW_BLK_DSPP, hw_dspp,
 		ARRAY_SIZE(hw_dspp));
 
@@ -1084,7 +1098,7 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 	}
 
 	cstate->num_mixers = num_lm;
-
+	cstate->ctm_enabled = !!num_dspp;
 	dpu_enc->connector = conn_state->connector;
 
 	for (i = 0; i < dpu_enc->num_phys_encs; i++) {
-- 
2.7.4