Re: [PATCH v2 4/7] drm/msm/dsi: Reuse earlier computed dsc->slice_chunk_size

[Abhinav Kumar <quic_abhinavk@quicinc.com>]

On 10/5/2022 11:16 AM, Marijn Suijten wrote:
> dsi_populate_dsc_params() is called prior to dsi_update_dsc_timing() and
> already computes a value for slice_chunk_size, whose value doesn't need
> to be recomputed and re-set here.
> 
> Fixes: 08802f515c3c ("drm/msm/dsi: Add support for DSC configuration")
> Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
> ---
>   drivers/gpu/drm/msm/dsi/dsi_host.c | 9 ++-------
>   1 file changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
> index 48c966375ffa..f42794cdd4c1 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> @@ -845,7 +845,6 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
>   	u32 reg, reg_ctrl, reg_ctrl2;
>   	u32 slice_per_intf, total_bytes_per_intf;
>   	u32 pkt_per_line;
> -	u32 bytes_in_slice;
>   	u32 eol_byte_num;
>   
>   	/* first calculate dsc parameters and then program
> @@ -860,11 +859,7 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
>   	if (slice_per_intf > dsc->slice_count)
>   		dsc->slice_count = 1;
>   
> -	bytes_in_slice = DIV_ROUND_UP(dsc->slice_width * dsc->bits_per_pixel, 8);
> -
> -	dsc->slice_chunk_size = bytes_in_slice;
> -
> -	total_bytes_per_intf = bytes_in_slice * slice_per_intf;
> +	total_bytes_per_intf = dsc->slice_chunk_size * slice_per_intf;
>   
>   	eol_byte_num = total_bytes_per_intf % 3;
>   	pkt_per_line = slice_per_intf / dsc->slice_count;
> @@ -890,7 +885,7 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
>   		reg_ctrl |= reg;
>   
>   		reg_ctrl2 &= ~DSI_COMMAND_COMPRESSION_MODE_CTRL2_STREAM0_SLICE_WIDTH__MASK;
> -		reg_ctrl2 |= DSI_COMMAND_COMPRESSION_MODE_CTRL2_STREAM0_SLICE_WIDTH(bytes_in_slice);
> +		reg_ctrl2 |= DSI_COMMAND_COMPRESSION_MODE_CTRL2_STREAM0_SLICE_WIDTH(dsc->slice_chunk_size);
>   
>   		dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL, reg_ctrl);
>   		dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL2, reg_ctrl2);