Re: [PATCH] drm/msm/dpu: Clean up CRC debug logs

[Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>]

Hi Jessica

Please add reported by for dmitry and suggested-by for Rob.

Thanks

Abhinav

On 4/29/2022 5:39 PM, Jessica Zhang wrote:
> Currently, dpu_hw_lm_collect_misr returns EINVAL if CRC is disabled.
> This causes a lot of spam in the DRM debug logs as it's called for every
> vblank.
>
> Instead of returning EINVAL when CRC is disabled in
> dpu_hw_lm_collect_misr, let's return ENODATA and add an extra ENODATA check
> before the debug log in dpu_crtc_get_crc.
>
> Signed-off-by: Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>
> Tested-by: Jessica Zhang <quic_jesszhan@xxxxxxxxxxx> # RB5  (qrb5165)
> ---
>   drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c  | 3 ++-
>   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c | 2 +-
>   2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> index 7763558ef566..16ba9f9b9a78 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> @@ -204,7 +204,8 @@ static int dpu_crtc_get_crc(struct drm_crtc *crtc)
>   		rc = m->hw_lm->ops.collect_misr(m->hw_lm, &crcs[i]);
>   
>   		if (rc) {
> -			DRM_DEBUG_DRIVER("MISR read failed\n");
> +			if (rc != -ENODATA)
> +				DRM_DEBUG_DRIVER("MISR read failed\n");
>   			return rc;
>   		}
>   	}
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c
> index 86363c0ec834..462f5082099e 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c
> @@ -138,7 +138,7 @@ static int dpu_hw_lm_collect_misr(struct dpu_hw_mixer *ctx, u32 *misr_value)
>   	ctrl = DPU_REG_READ(c, LM_MISR_CTRL);
>   
>   	if (!(ctrl & LM_MISR_CTRL_ENABLE))
> -		return -EINVAL;
> +		return -ENODATA;
>   
>   	if (!(ctrl & LM_MISR_CTRL_STATUS))
>   		return -EINVAL;