This patch correct calculation formula of PHY timing. The spec define HS-PREPARE should be from 40ns+4*UI(44ns) to 85ns+6*UI(91ns). But current duration is 88ns and is near the boundary. So this patch make the duration to 64ns so it is near the safe range. Signed-off-by: Shuijing Li <shuijing.li@xxxxxxxxxxxx> --- Changes in v2: Add a commit to describe the improvements to this patch in detail, per suggestion frome previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20240315072945.19502-1-shuijing.li@xxxxxxxxxxxx/ --- drivers/gpu/drm/mediatek/mtk_dsi.c | 33 +++++++++++++++--------------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c index a2fdfc8ddb15..d1bd7d671880 100644 --- a/drivers/gpu/drm/mediatek/mtk_dsi.c +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c @@ -235,22 +235,23 @@ static void mtk_dsi_phy_timconfig(struct mtk_dsi *dsi) u32 data_rate_mhz = DIV_ROUND_UP(dsi->data_rate, 1000000); struct mtk_phy_timing *timing = &dsi->phy_timing; - timing->lpx = (60 * data_rate_mhz / (8 * 1000)) + 1; - timing->da_hs_prepare = (80 * data_rate_mhz + 4 * 1000) / 8000; - timing->da_hs_zero = (170 * data_rate_mhz + 10 * 1000) / 8000 + 1 - - timing->da_hs_prepare; - timing->da_hs_trail = timing->da_hs_prepare + 1; - - timing->ta_go = 4 * timing->lpx - 2; - timing->ta_sure = timing->lpx + 2; - timing->ta_get = 4 * timing->lpx; - timing->da_hs_exit = 2 * timing->lpx + 1; - - timing->clk_hs_prepare = 70 * data_rate_mhz / (8 * 1000); - timing->clk_hs_post = timing->clk_hs_prepare + 8; - timing->clk_hs_trail = timing->clk_hs_prepare; - timing->clk_hs_zero = timing->clk_hs_trail * 4; - timing->clk_hs_exit = 2 * timing->clk_hs_trail; + timing->lpx = (80 * data_rate_mhz / (8 * 1000)) + 1; + timing->da_hs_prepare = (59 * data_rate_mhz + 4 * 1000) / 8000 + 1; + timing->da_hs_zero = (163 * data_rate_mhz + 11 * 1000) / 8000 + 1 - + timing->da_hs_prepare; + timing->da_hs_trail = (78 * data_rate_mhz + 7 * 1000) / 8000 + 1; + + timing->ta_go = 4 * timing->lpx; + timing->ta_sure = 3 * timing->lpx / 2; + timing->ta_get = 5 * timing->lpx; + timing->da_hs_exit = (118 * data_rate_mhz / (8 * 1000)) + 1; + + timing->clk_hs_prepare = (57 * data_rate_mhz / (8 * 1000)) + 1; + timing->clk_hs_post = (65 * data_rate_mhz + 53 * 1000) / 8000 + 1; + timing->clk_hs_trail = (78 * data_rate_mhz + 7 * 1000) / 8000 + 1; + timing->clk_hs_zero = (330 * data_rate_mhz / (8 * 1000)) + 1 - + timing->clk_hs_prepare; + timing->clk_hs_exit = (118 * data_rate_mhz / (8 * 1000)) + 1; timcon0 = timing->lpx | timing->da_hs_prepare << 8 | timing->da_hs_zero << 16 | timing->da_hs_trail << 24; -- 2.43.0
