From: Deepak M <m.deepak@xxxxxxxxx> For GEMINILAKE, dphy param reg values are programmed in terms of HS byte clock count while for older platforms in terms of HS ddr clk count. v2: Added comments to clarify ddr clock count calculation v3: Use multiplier variable instead of IS_GEMINILAKE() check everywhere (Jani) Signed-off-by: Deepak M <m.deepak@xxxxxxxxx> Signed-off-by: Madhav Chauhan <madhav.chauhan@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_dsi_panel_vbt.c | 31 +++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c index 8f683b8..d06e7f7 100644 --- a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c +++ b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c @@ -571,6 +571,7 @@ struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id) u32 tclk_prepare_clkzero, ths_prepare_hszero; u32 lp_to_hs_switch, hs_to_lp_switch; u32 pclk, computed_ddr; + u32 mul; u16 burst_mode_ratio; enum port port; @@ -674,11 +675,6 @@ struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id) break; } - /* - * ui(s) = 1/f [f in hz] - * ui(ns) = 10^9 / (f*10^6) [f in Mhz] -> 10^3/f(Mhz) - */ - /* in Kbps */ ui_num = NS_KHZ_RATIO; ui_den = bitrate; @@ -692,21 +688,26 @@ struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id) */ intel_dsi->lp_byte_clk = DIV_ROUND_UP(tlpx_ns * ui_den, 8 * ui_num); - /* count values in UI = (ns value) * (bitrate / (2 * 10^6)) + /* DDR clock period = 2 * UI + * UI(sec) = 1/(bitrate * 10^3) (bitrate is in KHZ) + * UI(nsec) = 10^6 / bitrate + * DDR clock period (nsec) = 2 * UI = (2 * 10^6)/ bitrate + * DDR clock count = ns_value / DDR clock period * - * Since txddrclkhs_i is 2xUI, all the count values programmed in - * DPHY param register are divided by 2 - * - * prepare count + * For GEMINILAKE dphy_param_reg will be programmed in terms of + * HS byte clock count for other platform in HS ddr clock count */ + mul = IS_GEMINILAKE(dev_priv) ? 8 : 2; ths_prepare_ns = max(mipi_config->ths_prepare, mipi_config->tclk_prepare); - prepare_cnt = DIV_ROUND_UP(ths_prepare_ns * ui_den, ui_num * 2); + + /* prepare count */ + prepare_cnt = DIV_ROUND_UP(ths_prepare_ns * ui_den, ui_num * mul); /* exit zero count */ exit_zero_cnt = DIV_ROUND_UP( (ths_prepare_hszero - ths_prepare_ns) * ui_den, - ui_num * 2 + ui_num * mul ); /* @@ -720,12 +721,12 @@ struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id) /* clk zero count */ clk_zero_cnt = DIV_ROUND_UP( - (tclk_prepare_clkzero - ths_prepare_ns) - * ui_den, 2 * ui_num); + (tclk_prepare_clkzero - ths_prepare_ns) + * ui_den, ui_num * mul); /* trail count */ tclk_trail_ns = max(mipi_config->tclk_trail, mipi_config->ths_trail); - trail_cnt = DIV_ROUND_UP(tclk_trail_ns * ui_den, 2 * ui_num); + trail_cnt = DIV_ROUND_UP(tclk_trail_ns * ui_den, ui_num * mul); if (prepare_cnt > PREPARE_CNT_MAX || exit_zero_cnt > EXIT_ZERO_CNT_MAX || -- 1.9.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx