Re: [PATCH v7 2/3] drm/mediatek: implment the dsi hs packets aligned

From: Chun-Kuang Hu
Date: Wed Sep 29 2021 - 10:59:44 EST


Hi, Jitao:

Jitao Shi <jitao.shi@xxxxxxxxxxxx> 於 2021年9月16日 週四 上午6:31寫道:
>
> Some dsi devices require the packets on lanes aligned at the end,
> or the screen will shift or scroll.

Reviewed-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>

>
> Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/mediatek/mtk_dsi.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 93b40c245f00..9d72e6dce0bf 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -194,6 +194,8 @@ struct mtk_dsi {
> struct clk *hs_clk;
>
> u32 data_rate;
> + /* force dsi line end without dsi_null data */
> + bool hs_packet_end_aligned;
>
> unsigned long mode_flags;
> enum mipi_dsi_pixel_format format;
> @@ -499,6 +501,13 @@ static void mtk_dsi_config_vdo_timing(struct mtk_dsi *dsi)
> DRM_WARN("HFP + HBP less than d-phy, FPS will under 60Hz\n");
> }
>
> + if (dsi->hs_packet_end_aligned) {
> + horizontal_sync_active_byte = roundup(horizontal_sync_active_byte, dsi->lanes) - 2;
> + horizontal_frontporch_byte = roundup(horizontal_frontporch_byte, dsi->lanes) - 2;
> + horizontal_backporch_byte = roundup(horizontal_backporch_byte, dsi->lanes) - 2;
> + horizontal_backporch_byte -= (vm->hactive * dsi_tmp_buf_bpp + 2) % dsi->lanes;
> + }
> +
> writel(horizontal_sync_active_byte, dsi->regs + DSI_HSA_WC);
> writel(horizontal_backporch_byte, dsi->regs + DSI_HBP_WC);
> writel(horizontal_frontporch_byte, dsi->regs + DSI_HFP_WC);
> @@ -793,6 +802,7 @@ static int mtk_dsi_host_attach(struct mipi_dsi_host *host,
> dsi->lanes = device->lanes;
> dsi->format = device->format;
> dsi->mode_flags = device->mode_flags;
> + dsi->hs_packet_end_aligned = device->hs_packet_end_aligned;
>
> return 0;
> }
> --
> 2.25.1