Hi CK, On Mon, 16 Nov 2020 07:12:55 +0800 Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> wrote: > Hi, Bilal: > > Bilal Wasim <bilalwasim676@xxxxxxxxx> 於 2020年11月16日 週一 > 上午3:25寫道: > > > > Hi CK, > > > > On Sun, 15 Nov 2020 08:53:24 +0800 > > Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> wrote: > > > > > Hi, Bilal: > > > > > > Please help to test this patch on your Chromebook elm, thanks. > > > > > > Regards, > > > Chun-Kuang Hu > > > > Just tried this patch on the Chromebook Elm, and it doesn't work. > > The HDMI screen remains black, though the rest of the system keeps > > on operating normally. > > Could you print this information, so I could find out the solution for > both small hbp and elm. > > vm->hfront_porch, vm->hback_porch, dsi_tmp_buf_bpp, > data_phy_cycles_byte, and the final horizontal_frontporch_byte, > horizontal_backporch_byte. Here are the values I got, [ 2.506400] [drm] vm->hfront_porch: 48 [ 2.506402] [drm] vm->hback_porch: 200 [ 2.506404] [drm] dsi_tmp_buf_bpp: 3 [ 2.506406] [drm] data_phy_cycles_byte: 180 [ 2.506408] [drm] horizontal_frontporch_byte: 110 [ 2.506409] [drm] horizontal_backporch_byte: 455 Please let me know if I can help debug this in any other way. Thanks, Bilal > > Regards, > Chun-Kuang. > > > > > > > > > Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> 於 2020年11月15日 週日 > > > 上午8:14寫道: > > > > > > > > From: CK Hu <ck.hu@xxxxxxxxxxxx> > > > > > > > > Using vm->hfront_porch + vm->hback_porch to calculate > > > > horizontal_backporch_byte would make it negtive, so > > > > use horizontal_backporch_byte itself to make it positive. > > > > > > > > Fixes: 35bf948f1edb ("drm/mediatek: dsi: Fix scrolling of panel > > > > with small hfp or hbp") > > > > > > > > Signed-off-by: CK Hu <ck.hu@xxxxxxxxxxxx> > > > > Signed-off-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> > > > > --- > > > > drivers/gpu/drm/mediatek/mtk_dsi.c | 53 > > > > ++++++++++-------------------- 1 file changed, 18 > > > > insertions(+), 35 deletions(-) > > > > > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c > > > > b/drivers/gpu/drm/mediatek/mtk_dsi.c index > > > > 4a188a942c38..2a64fdaed9a7 100644 --- > > > > a/drivers/gpu/drm/mediatek/mtk_dsi.c +++ > > > > b/drivers/gpu/drm/mediatek/mtk_dsi.c @@ -444,7 +444,10 @@ static > > > > void mtk_dsi_config_vdo_timing(struct mtk_dsi *dsi) u32 > > > > horizontal_sync_active_byte; u32 horizontal_backporch_byte; > > > > u32 horizontal_frontporch_byte; > > > > + u32 horizontal_front_back_byte; > > > > + u32 data_phy_cycles_byte; > > > > u32 dsi_tmp_buf_bpp, data_phy_cycles; > > > > + u32 delta; > > > > struct mtk_phy_timing *timing = &dsi->phy_timing; > > > > > > > > struct videomode *vm = &dsi->vm; > > > > @@ -474,42 +477,22 @@ static void > > > > mtk_dsi_config_vdo_timing(struct mtk_dsi *dsi) data_phy_cycles > > > > = timing->lpx + timing->da_hs_prepare > > > > + timing->da_hs_zero + timing->da_hs_exit; > > > > > > > > - if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) { > > > > - if ((vm->hfront_porch + vm->hback_porch) * > > > > dsi_tmp_buf_bpp > > > > > - data_phy_cycles * dsi->lanes + 18) { > > > > - horizontal_frontporch_byte = > > > > - vm->hfront_porch * > > > > dsi_tmp_buf_bpp - > > > > - (data_phy_cycles * dsi->lanes + > > > > 18) * > > > > - vm->hfront_porch / > > > > - (vm->hfront_porch + > > > > vm->hback_porch); - > > > > - horizontal_backporch_byte = > > > > - horizontal_backporch_byte - > > > > - (data_phy_cycles * dsi->lanes + > > > > 18) * > > > > - vm->hback_porch / > > > > - (vm->hfront_porch + > > > > vm->hback_porch); > > > > - } else { > > > > - DRM_WARN("HFP less than d-phy, FPS will > > > > under 60Hz\n"); > > > > - horizontal_frontporch_byte = > > > > vm->hfront_porch * > > > > - > > > > dsi_tmp_buf_bpp; > > > > - } > > > > + delta = dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST ? > > > > 18 : 12; + > > > > + horizontal_frontporch_byte = vm->hfront_porch * > > > > dsi_tmp_buf_bpp; > > > > + horizontal_front_back_byte = horizontal_frontporch_byte > > > > + horizontal_backporch_byte; > > > > + data_phy_cycles_byte = data_phy_cycles * dsi->lanes + > > > > delta; + > > > > + if (horizontal_front_back_byte > data_phy_cycles_byte) { > > > > + horizontal_frontporch_byte -= > > > > data_phy_cycles_byte * + > > > > horizontal_frontporch_byte / > > > > + > > > > horizontal_front_back_byte; + > > > > + horizontal_backporch_byte -= > > > > data_phy_cycles_byte * + > > > > horizontal_backporch_byte / > > > > + > > > > horizontal_front_back_byte; } else { > > > > - if ((vm->hfront_porch + vm->hback_porch) * > > > > dsi_tmp_buf_bpp > > > > > - data_phy_cycles * dsi->lanes + 12) { > > > > - horizontal_frontporch_byte = > > > > - vm->hfront_porch * > > > > dsi_tmp_buf_bpp - > > > > - (data_phy_cycles * dsi->lanes + > > > > 12) * > > > > - vm->hfront_porch / > > > > - (vm->hfront_porch + > > > > vm->hback_porch); > > > > - horizontal_backporch_byte = > > > > horizontal_backporch_byte - > > > > - (data_phy_cycles * dsi->lanes + > > > > 12) * > > > > - vm->hback_porch / > > > > - (vm->hfront_porch + > > > > vm->hback_porch); > > > > - } else { > > > > - DRM_WARN("HFP less than d-phy, FPS will > > > > under 60Hz\n"); > > > > - horizontal_frontporch_byte = > > > > vm->hfront_porch * > > > > - > > > > dsi_tmp_buf_bpp; > > > > - } > > > > + DRM_WARN("HFP + HBP less than d-phy, FPS will > > > > under 60Hz\n"); } > > > > > > > > writel(horizontal_sync_active_byte, dsi->regs + > > > > DSI_HSA_WC); -- > > > > 2.17.1 > > > > > > > > Thanks, > > Bilal _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel