On Thu, 14 Sep 2023, William Tseng <[email protected]> wrote:
> This change is to adjust TCLK-POST timing so DSI signaling can
> meet CTS specification.
>
> For clock lane, the TCLK-POST timing may be changed from
> 133.44 ns to 178.72 ns, which is greater than (60 ns+52*UI)
> and is conformed to the CTS standard.
>
> The computed UI is around 1.47 ns.
>
> v2: remove the change of HS-TRAIL.
>
> Cc: Ville Syrjala <[email protected]>
> Cc: Jani Nikula <[email protected]>
> Cc: Vandita Kulkarni <[email protected]>
> Cc: Suraj Kandpal <[email protected]>
> Cc: Lee Shawn C <[email protected]>
> Signed-off-by: William Tseng <[email protected]>
Thanks, pushed to drm-intel-next.
BR,
Jani.
> ---
> drivers/gpu/drm/i915/display/icl_dsi.c | 13 +------------
> 1 file changed, 1 insertion(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c
> b/drivers/gpu/drm/i915/display/icl_dsi.c
> index ad6488e9c2b2..c4585e445198 100644
> --- a/drivers/gpu/drm/i915/display/icl_dsi.c
> +++ b/drivers/gpu/drm/i915/display/icl_dsi.c
> @@ -1822,7 +1822,7 @@ static void icl_dphy_param_init(struct intel_dsi
> *intel_dsi)
> u32 prepare_cnt, exit_zero_cnt, clk_zero_cnt, trail_cnt;
> u32 ths_prepare_ns, tclk_trail_ns;
> u32 hs_zero_cnt;
> - u32 tclk_pre_cnt, tclk_post_cnt;
> + u32 tclk_pre_cnt;
>
> tlpx_ns = intel_dsi_tlpx_ns(intel_dsi);
>
> @@ -1869,15 +1869,6 @@ static void icl_dphy_param_init(struct intel_dsi
> *intel_dsi)
> tclk_pre_cnt = ICL_TCLK_PRE_CNT_MAX;
> }
>
> - /* tclk post count in escape clocks */
> - tclk_post_cnt = DIV_ROUND_UP(mipi_config->tclk_post, tlpx_ns);
> - if (tclk_post_cnt > ICL_TCLK_POST_CNT_MAX) {
> - drm_dbg_kms(&dev_priv->drm,
> - "tclk_post_cnt out of range (%d)\n",
> - tclk_post_cnt);
> - tclk_post_cnt = ICL_TCLK_POST_CNT_MAX;
> - }
> -
> /* hs zero cnt in escape clocks */
> hs_zero_cnt = DIV_ROUND_UP(mipi_config->ths_prepare_hszero -
> ths_prepare_ns, tlpx_ns);
> @@ -1903,8 +1894,6 @@ static void icl_dphy_param_init(struct intel_dsi
> *intel_dsi)
> CLK_ZERO(clk_zero_cnt) |
> CLK_PRE_OVERRIDE |
> CLK_PRE(tclk_pre_cnt) |
> - CLK_POST_OVERRIDE |
> - CLK_POST(tclk_post_cnt) |
> CLK_TRAIL_OVERRIDE |
> CLK_TRAIL(trail_cnt));
--
Jani Nikula, Intel
