Hi, Bilal: Please help to test this patch on your Chromebook elm, thanks. Regards, Chun-Kuang Hu 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 > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel