Re: [PATCH] drm/msm/dp: remove limitation of link rate at 5.4G to support HBR3

[Dmitry Baryshkov]

On 31/10/2022 20:27, Kuogee Hsieh wrote:
> An HBR3-capable device shall also support TPS4. Since TPS4 feature
> had been implemented already, it is not necessary to limit link
> rate at HBR2 (5.4G). This patch remove this limitation to support
> HBR3 (8.1G) link rate.

The DP driver supports several platforms including sdm845 and can 
support, if I'm not mistaken, platforms up to msm8998/sdm630/660. Could 
you please confirm that all these SoCs have support for HBR3?

With that fact being confirmed:

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>


> Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
> ---
>   drivers/gpu/drm/msm/dp/dp_panel.c | 4 ----
>   1 file changed, 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c b/drivers/gpu/drm/msm/dp/dp_panel.c
> index 5149ceb..3344f5a 100644
> --- a/drivers/gpu/drm/msm/dp/dp_panel.c
> +++ b/drivers/gpu/drm/msm/dp/dp_panel.c
> @@ -78,10 +78,6 @@ static int dp_panel_read_dpcd(struct dp_panel *dp_panel)
>   	if (link_info->num_lanes > dp_panel->max_dp_lanes)
>   		link_info->num_lanes = dp_panel->max_dp_lanes;
>   
> -	/* Limit support upto HBR2 until HBR3 support is added */
> -	if (link_info->rate >= (drm_dp_bw_code_to_link_rate(DP_LINK_BW_5_4)))
> -		link_info->rate = drm_dp_bw_code_to_link_rate(DP_LINK_BW_5_4);
> -
>   	drm_dbg_dp(panel->drm_dev, "version: %d.%d\n", major, minor);
>   	drm_dbg_dp(panel->drm_dev, "link_rate=%d\n", link_info->rate);
>   	drm_dbg_dp(panel->drm_dev, "lane_count=%d\n", link_info->num_lanes);

--
With best wishes
Dmitry