Re: [PATCH v2 14/16] drm/msm/dpu: reserve cdm blocks for writeback in case of YUV output

Dmitry Baryshkov
2023-12-08T11:54:34Z

On Fri, 8 Dec 2023 at 07:07, Abhinav Kumar <quic_abhinavk@quicinc.com> wrote:
>
> Reserve CDM blocks for writeback if the format of the output fb
> is YUV. At the moment, the reservation is done only for writeback
> but can easily be extended by relaxing the checks once other
> interfaces are ready to output YUV.
>
> changes in v2:
> - use needs_cdm from topology struct
> - drop fb related checks from atomic_mode_set()

It looks like this should be squashed with the patch 11. The 'unbind
CDM' doesn't really make sense without this patch. We need to allocate
it first, before touching it.

>
> Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 27 +++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> index 862912727925..a576e3e62429 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> @@ -16,6 +16,7 @@
> #include <drm/drm_crtc.h>
> #include <drm/drm_file.h>
> #include <drm/drm_probe_helper.h>
> +#include <drm/drm_framebuffer.h>
>
> #include "msm_drv.h"
> #include "dpu_kms.h"
> @@ -583,6 +584,7 @@ static int dpu_encoder_virt_atomic_check(
> struct drm_display_mode *adj_mode;
> struct msm_display_topology topology;
> struct dpu_global_state *global_state;
> + struct drm_framebuffer *fb;
> struct drm_dsc_config *dsc;
> int i = 0;
> int ret = 0;
> @@ -623,6 +625,22 @@ static int dpu_encoder_virt_atomic_check(
>
> topology = dpu_encoder_get_topology(dpu_enc, dpu_kms, adj_mode, crtc_state, dsc);
>
> + /*
> + * Use CDM only for writeback at the moment as other interfaces cannot handle it.
> + * if writeback itself cannot handle cdm for some reason it will fail in its atomic_check()
> + * earlier.
> + */
> + if (dpu_enc->disp_info.intf_type == INTF_WB && conn_state->writeback_job) {
> + fb = conn_state->writeback_job->fb;
> +
> + if (fb && DPU_FORMAT_IS_YUV(to_dpu_format(msm_framebuffer_format(fb))))
> + topology.needs_cdm = true;
> + if (topology.needs_cdm && !dpu_enc->cur_master->hw_cdm)
> + crtc_state->mode_changed = true;
> + else if (!topology.needs_cdm && dpu_enc->cur_master->hw_cdm)
> + crtc_state->mode_changed = true;
> + }
> +
> /*
> * Release and Allocate resources on every modeset
> * Dont allocate when active is false.
> @@ -1063,6 +1081,15 @@ static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
>
> dpu_enc->dsc_mask = dsc_mask;
>
> + if (dpu_enc->disp_info.intf_type == INTF_WB && conn_state->writeback_job) {
> + struct dpu_hw_blk *hw_cdm = NULL;
> +
> + dpu_rm_get_assigned_resources(&dpu_kms->rm, global_state,
> + drm_enc->base.id, DPU_HW_BLK_CDM,
> + &hw_cdm, 1);
> + dpu_enc->cur_master->hw_cdm = hw_cdm ? to_dpu_hw_cdm(hw_cdm) : NULL;
> + }
> +
> cstate = to_dpu_crtc_state(crtc_state);
>
> for (i = 0; i < num_lm; i++) {
> --
> 2.40.1
>

--
With best wishes

Dmitry