[PATCH v10 10/12] drm/msm/dpu: support SSPP assignment for quad-pipe case
Dmitry Baryshkov
dmitry.baryshkov at oss.qualcomm.com
Wed May 28 18:22:15 UTC 2025
On Mon, May 26, 2025 at 05:28:28PM +0800, Jun Nie wrote:
> Currently, SSPPs are assigned to a maximum of two pipes. However,
> quad-pipe usage scenarios require four pipes and involve configuring
> two stages. In quad-pipe case, the first two pipes share a set of
> mixer configurations and enable multi-rect mode when certain
> conditions are met. The same applies to the subsequent two pipes.
>
> Assign SSPPs to the pipes in each stage using a unified method and
> to loop the stages accordingly.
>
> Signed-off-by: Jun Nie <jun.nie at linaro.org>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 11 +++
> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h | 2 +
> drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 126 ++++++++++++++++++------------
> 3 files changed, 88 insertions(+), 51 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> index 85f585206218f4578e18b00452762dbada060e9c..47ab43dfec76acc058fb275d1928603e8e8e7fc6 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> @@ -1562,6 +1562,17 @@ int dpu_crtc_vblank(struct drm_crtc *crtc, bool en)
> return 0;
> }
>
> +/**
> + * dpu_crtc_get_num_lm - Get mixer number in this CRTC pipeline
> + * @state: Pointer to drm crtc state object
> + */
> +unsigned int dpu_crtc_get_num_lm(const struct drm_crtc_state *state)
> +{
> + struct dpu_crtc_state *cstate = to_dpu_crtc_state(state);
> +
> + return cstate->num_mixers;
> +}
> +
> #ifdef CONFIG_DEBUG_FS
> static int _dpu_debugfs_status_show(struct seq_file *s, void *data)
> {
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
> index 94392b9b924546f96e738ae20920cf9afd568e6b..6eaba5696e8e6bd1246a9895c4c8714ca6589b10 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
> @@ -267,4 +267,6 @@ static inline enum dpu_crtc_client_type dpu_crtc_get_client_type(
>
> void dpu_crtc_frame_event_cb(struct drm_crtc *crtc, u32 event);
>
> +unsigned int dpu_crtc_get_num_lm(const struct drm_crtc_state *state);
> +
> #endif /* _DPU_CRTC_H_ */
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> index 0bb153a71353ca9eaca138ebbee4cd699414771d..f721dc504bbbe3a49986239adee113bfb6790f70 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> @@ -961,6 +961,33 @@ static int dpu_plane_is_multirect_parallel_capable(struct dpu_hw_sspp *sspp,
> dpu_plane_is_parallel_capable(pipe_cfg, fmt, max_linewidth);
> }
>
> +static bool dpu_plane_check_single_pipe(struct dpu_plane_state *pstate,
> + struct dpu_sw_pipe **single_pipe,
> + struct dpu_sw_pipe_cfg **single_pipe_cfg,
> + bool config_pipe)
> +{
> + int i, valid_pipe = 0;
> + struct dpu_sw_pipe *pipe;
> +
> + for (i = 0; i < PIPES_PER_PLANE; i++) {
> + if (drm_rect_width(&pstate->pipe_cfg[i].src_rect) != 0) {
> + valid_pipe++;
> + if (valid_pipe > 1)
> + return false;
> + *single_pipe = &pstate->pipe[i];
> + *single_pipe_cfg = &pstate->pipe_cfg[i];
> + } else {
> + if (!config_pipe)
> + continue;
> + pipe = &pstate->pipe[i];
> + pipe->multirect_index = DPU_SSPP_RECT_SOLO;
> + pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
> + pipe->sspp = NULL;
If this function is 'check', then why does it change something in the
pipe configuration?
> + }
> + }
> +
> + return true;
> +}
>
> static int dpu_plane_atomic_check_sspp(struct drm_plane *plane,
> struct drm_atomic_state *state,
> @@ -1028,15 +1055,15 @@ static int dpu_plane_try_multirect_shared(struct dpu_plane_state *pstate,
> const struct msm_format *fmt,
> uint32_t max_linewidth)
> {
> - struct dpu_sw_pipe *pipe = &pstate->pipe[0];
> - struct dpu_sw_pipe *r_pipe = &pstate->pipe[1];
> - struct dpu_sw_pipe_cfg *pipe_cfg = &pstate->pipe_cfg[0];
> - struct dpu_sw_pipe *prev_pipe = &prev_adjacent_pstate->pipe[0];
> - struct dpu_sw_pipe_cfg *prev_pipe_cfg = &prev_adjacent_pstate->pipe_cfg[0];
> + struct dpu_sw_pipe *pipe, *prev_pipe;
> + struct dpu_sw_pipe_cfg *pipe_cfg, *prev_pipe_cfg;
> const struct msm_format *prev_fmt = msm_framebuffer_format(prev_adjacent_pstate->base.fb);
> u16 max_tile_height = 1;
>
> - if (prev_adjacent_pstate->pipe[1].sspp != NULL ||
> + if (!dpu_plane_check_single_pipe(pstate, &pipe, &pipe_cfg, true))
> + return false;
> +
> + if (!dpu_plane_check_single_pipe(prev_adjacent_pstate, &prev_pipe, &prev_pipe_cfg, false) ||
> prev_pipe->multirect_mode != DPU_SSPP_MULTIRECT_NONE)
> return false;
>
> @@ -1050,11 +1077,6 @@ static int dpu_plane_try_multirect_shared(struct dpu_plane_state *pstate,
> if (MSM_FORMAT_IS_UBWC(prev_fmt))
> max_tile_height = max(max_tile_height, prev_fmt->tile_height);
>
> - r_pipe->multirect_index = DPU_SSPP_RECT_SOLO;
> - r_pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
> -
> - r_pipe->sspp = NULL;
> -
> if (dpu_plane_is_parallel_capable(pipe_cfg, fmt, max_linewidth) &&
> dpu_plane_is_parallel_capable(prev_pipe_cfg, prev_fmt, max_linewidth) &&
> (pipe_cfg->dst_rect.x1 >= prev_pipe_cfg->dst_rect.x2 ||
> @@ -1194,12 +1216,11 @@ static int dpu_plane_virtual_assign_resources(struct drm_crtc *crtc,
> struct dpu_kms *dpu_kms = _dpu_plane_get_kms(plane);
> struct dpu_rm_sspp_requirements reqs;
> struct dpu_plane_state *pstate, *prev_adjacent_pstate;
> - struct dpu_sw_pipe *pipe;
> - struct dpu_sw_pipe *r_pipe;
> - struct dpu_sw_pipe_cfg *pipe_cfg;
> - struct dpu_sw_pipe_cfg *r_pipe_cfg;
> + struct dpu_sw_pipe *pipe, *r_pipe;
> + struct dpu_sw_pipe_cfg *pipe_cfg, *r_pipe_cfg;
> + struct dpu_plane *pdpu = to_dpu_plane(plane);
> const struct msm_format *fmt;
> - int i;
> + int i, num_lm, stage_id, num_stages;
>
> if (plane_state->crtc)
> crtc_state = drm_atomic_get_new_crtc_state(state,
> @@ -1209,11 +1230,6 @@ static int dpu_plane_virtual_assign_resources(struct drm_crtc *crtc,
> prev_adjacent_pstate = prev_adjacent_plane_state ?
> to_dpu_plane_state(prev_adjacent_plane_state) : NULL;
>
> - pipe = &pstate->pipe[0];
> - r_pipe = &pstate->pipe[1];
> - pipe_cfg = &pstate->pipe_cfg[0];
> - r_pipe_cfg = &pstate->pipe_cfg[1];
> -
> for (i = 0; i < PIPES_PER_PLANE; i++)
> pstate->pipe[i].sspp = NULL;
>
> @@ -1227,44 +1243,52 @@ static int dpu_plane_virtual_assign_resources(struct drm_crtc *crtc,
>
> reqs.rot90 = drm_rotation_90_or_270(plane_state->rotation);
>
> - if (drm_rect_width(&r_pipe_cfg->src_rect) == 0) {
> - if (!prev_adjacent_pstate ||
> - !dpu_plane_try_multirect_shared(pstate, prev_adjacent_pstate, fmt,
> - dpu_kms->catalog->caps->max_linewidth)) {
> - pipe->sspp = dpu_rm_reserve_sspp(&dpu_kms->rm, global_state, crtc, &reqs);
> - if (!pipe->sspp)
> - return -ENODEV;
> + if (prev_adjacent_pstate &&
> + dpu_plane_try_multirect_shared(pstate, prev_adjacent_pstate, fmt,
> + dpu_kms->catalog->caps->max_linewidth)) {
> + goto assigned;
> + }
>
> - r_pipe->sspp = NULL;
> + num_lm = dpu_crtc_get_num_lm(crtc_state);
> + num_stages = (num_lm + 1) / 2;
> + for (stage_id = 0; stage_id < num_stages; stage_id++) {
Can't we just loop through all possible stages? Same result, but makes
the logic somewhat easier.
> + for (i = stage_id * PIPES_PER_STAGE; i < (stage_id + 1) * PIPES_PER_STAGE; i++) {
I still really don't like this idea (and especially the part with
(i % PIPES_PER_STAGE == 0) condition). Extract current code which deals
with two planes and a single stage. Call it for each stage. That's it.
> + pipe = &pstate->pipe[i];
> + pipe_cfg = &pstate->pipe_cfg[i];
>
> - pipe->multirect_index = DPU_SSPP_RECT_SOLO;
> - pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
> + if (drm_rect_width(&pipe_cfg->src_rect) == 0)
> + break;
>
> - r_pipe->multirect_index = DPU_SSPP_RECT_SOLO;
> - r_pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
> - }
> - } else {
> - pipe->sspp = dpu_rm_reserve_sspp(&dpu_kms->rm, global_state, crtc, &reqs);
> - if (!pipe->sspp)
> - return -ENODEV;
> -
> - if (!dpu_plane_try_multirect_parallel(pipe, pipe_cfg, r_pipe, r_pipe_cfg,
> - pipe->sspp,
> - msm_framebuffer_format(plane_state->fb),
> - dpu_kms->catalog->caps->max_linewidth)) {
> - /* multirect is not possible, use two SSPP blocks */
> - r_pipe->sspp = dpu_rm_reserve_sspp(&dpu_kms->rm, global_state, crtc, &reqs);
> - if (!r_pipe->sspp)
> + pipe->sspp = dpu_rm_reserve_sspp(&dpu_kms->rm, global_state, crtc, &reqs);
> + if (!pipe->sspp)
> return -ENODEV;
>
> - pipe->multirect_index = DPU_SSPP_RECT_SOLO;
> - pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
> -
> - r_pipe->multirect_index = DPU_SSPP_RECT_SOLO;
> - r_pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
> + r_pipe = &pstate->pipe[i + 1];
> + r_pipe_cfg = &pstate->pipe_cfg[i + 1];
> +
> + /*
> + * If current pipe is the first pipe in pipe pair, check
> + * multi-rect opportunity for the 2nd pipe in the pair.
> + * SSPP multi-rect mode cross mixer pairs is not supported.
> + */
> + if ((i % PIPES_PER_STAGE == 0) &&
> + drm_rect_width(&r_pipe_cfg->src_rect) != 0 &&
> + dpu_plane_try_multirect_parallel(pipe, pipe_cfg, r_pipe, r_pipe_cfg,
> + pipe->sspp,
> + msm_framebuffer_format(plane_state->fb),
> + dpu_kms->catalog->caps->max_linewidth)) {
> + i++;
> + } else {
> + /* multirect is not possible, use two SSPP blocks */
> + pipe->multirect_index = DPU_SSPP_RECT_SOLO;
> + pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
> + DPU_DEBUG_PLANE(pdpu, "allocating sspp_%d for pipe %d.\n",
> + pipe->sspp->idx - SSPP_NONE, i);
> + }
> }
> }
>
> +assigned:
> return dpu_plane_atomic_check_sspp(plane, state, crtc_state);
> }
>
>
> --
> 2.34.1
>
--
With best wishes
Dmitry
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