Re: [PATCH v2 06/11] drm/msm/disp/dpu1: Don't use DSC with mode_3d

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

On 14/10/2021 16:41, Dmitry Baryshkov wrote:
> On 07/10/2021 10:08, Vinod Koul wrote:
>> We cannot enable mode_3d when we are using the DSC. So pass
>> configuration to detect DSC is enabled and not enable mode_3d
>> when we are using DSC
>>
>> We add a helper dpu_encoder_helper_get_dsc_mode() to detect dsc
>> enabled and pass this to .setup_intf_cfg()
>>
>> Signed-off-by: Vinod Koul <vkoul@kernel.org>
>> ---
>> Changes since
>> v1:
>>   - Move this patch from 7 to 6
>>   - Update the changelog
>>   - Make dsc as int and store the DSC indices
>>
>>   drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h     | 11 +++++++++++
>>   drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c |  2 ++
>>   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c           |  5 +++--
>>   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h           |  2 ++
>>   4 files changed, 18 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h 
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
>> index e7270eb6b84b..fca07ed03317 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
>> @@ -332,6 +332,17 @@ static inline enum dpu_3d_blend_mode 
>> dpu_encoder_helper_get_3d_blend_mode(
>>       return BLEND_3D_NONE;
>>   }
>> +static inline bool dpu_encoder_helper_get_dsc_mode(struct 
>> dpu_encoder_phys *phys_enc)
>> +{
>> +    struct drm_encoder *drm_enc = phys_enc->parent;
>> +    struct msm_drm_private *priv = drm_enc->dev->dev_private;
>> +
>> +    if (priv->dsc)
>> +        return BIT(0) | BIT(1); /* Hardcoding for 2 DSC topology */
> 
> Please use defined values here rater than just BIT().

Ah, it's a list of DSC blocks used. So the function name is misleading 
(as it's not a mode). I think we'd better pass DSC_n names here. What 
about using an array for cfg->dsc?

> 
>> +
>> +    return 0;
>> +}
>> +
>>   /**
>>    * dpu_encoder_helper_split_config - split display configuration 
>> helper function
>>    *    This helper function may be used by physical encoders to 
>> configure
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c 
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
>> index aa01698d6b25..8e5c0911734c 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
>> @@ -70,6 +70,8 @@ static void _dpu_encoder_phys_cmd_update_intf_cfg(
>>       intf_cfg.intf_mode_sel = DPU_CTL_MODE_SEL_CMD;
>>       intf_cfg.stream_sel = cmd_enc->stream_sel;
>>       intf_cfg.mode_3d = dpu_encoder_helper_get_3d_blend_mode(phys_enc);
>> +    intf_cfg.dsc = dpu_encoder_helper_get_dsc_mode(phys_enc);
>> +
>>       ctl->ops.setup_intf_cfg(ctl, &intf_cfg);
>>   }
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c 
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
>> index 64740ddb983e..3c79bd9c2fe5 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
>> @@ -118,7 +118,7 @@ static u32 dpu_hw_ctl_get_pending_flush(struct 
>> dpu_hw_ctl *ctx)
>>       return ctx->pending_flush_mask;
>>   }
>> -static inline void dpu_hw_ctl_trigger_flush_v1(struct dpu_hw_ctl *ctx)
>> +static void dpu_hw_ctl_trigger_flush_v1(struct dpu_hw_ctl *ctx)
>>   {
>>       if (ctx->pending_flush_mask & BIT(MERGE_3D_IDX))
>> @@ -519,7 +519,8 @@ static void dpu_hw_ctl_intf_cfg(struct dpu_hw_ctl 
>> *ctx,
>>       intf_cfg |= (cfg->intf & 0xF) << 4;
>> -    if (cfg->mode_3d) {
>> +    /* In DSC we can't set merge, so check for dsc too */
>> +    if (cfg->mode_3d && !cfg->dsc) {
> 
> The more I think about this hunk, the more I'm unsure about it.
> Downstream has the following topoligies defined:
>   * @SDE_RM_TOPOLOGY_DUALPIPE_3DMERGE_DSC: 2 LM, 2 PP, 3DMux, 1 DSC, 1 
> INTF/WB
>   * @SDE_RM_TOPOLOGY_QUADPIPE_3DMERGE_DSC  4 LM, 4 PP, 3DMux, 3 DSC, 2 INTF
> 
> While the latter is not supported on sdm845, the former one should be 
> (by the hardware). So in the driver I think we should make sure that 
> mode_3d does not get set rather than disallowing it here.
> 
>>           intf_cfg |= BIT(19);
>>           intf_cfg |= (cfg->mode_3d - 0x1) << 20;
>>       }
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h 
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
>> index 806c171e5df2..5dfac5994bd4 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
>> @@ -39,6 +39,7 @@ struct dpu_hw_stage_cfg {
>>    * @mode_3d:               3d mux configuration
>>    * @merge_3d:              3d merge block used
>>    * @intf_mode_sel:         Interface mode, cmd / vid
>> + * @dsc:                   DSC BIT masks
>>    * @stream_sel:            Stream selection for multi-stream interfaces
>>    */
>>   struct dpu_hw_intf_cfg {
>> @@ -46,6 +47,7 @@ struct dpu_hw_intf_cfg {
>>       enum dpu_3d_blend_mode mode_3d;
>>       enum dpu_merge_3d merge_3d;
>>       enum dpu_ctl_mode_sel intf_mode_sel;
>> +    unsigned int dsc;

I think this should be:
enum dpu_dsc dsc[MAX_DSCS];
unsigned int num_dsc;

>>       int stream_sel;
>>   };
>>
> 
> 


-- 
With best wishes
Dmitry