Re: [v4,PATCH 1/3] drm/mediatek: dpi dual edge sample mode support

From: Chun-Kuang Hu
Date: Tue May 25 2021 - 20:01:34 EST


Hi, Rex:

Rex-BC Chen <rex-bc.chen@xxxxxxxxxxxx> 於 2021年5月25日 週二 下午8:15寫道:
>
> DPI can sample on falling, rising or both edge.
> When DPI sample the data both rising and falling edge.
> It can reduce half data io pins.
> Use num_output_fmts to determine whether it is dual edge mode.
>
> Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
> Signed-off-by: Rex-BC Chen <rex-bc.chen@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/mediatek/mtk_dpi.c | 17 ++++++++++++++++-
> 1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
> index bea91c81626e..d3b883c97aaf 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dpi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
> @@ -83,6 +83,7 @@ struct mtk_dpi {
> struct pinctrl *pinctrl;
> struct pinctrl_state *pins_gpio;
> struct pinctrl_state *pins_dpi;
> + bool ddr_edge_sel;

I would like to keep output_fmt instead of ddr_edge_sel.
Initialize output_fmt to MEDIA_BUS_FMT_RGB888_1X24 in this patch.

> int refcount;
> };
>
> @@ -122,6 +123,8 @@ struct mtk_dpi_conf {
> u32 reg_h_fre_con;
> u32 max_clock_khz;
> bool edge_sel_en;
> + const u32 *output_fmts;
> + u32 num_output_fmts;

Move these to next patch.

> };
>
> static void mtk_dpi_mask(struct mtk_dpi *dpi, u32 offset, u32 val, u32 mask)
> @@ -381,6 +384,16 @@ static void mtk_dpi_config_color_format(struct mtk_dpi *dpi,
> }
> }
>
> +static void mtk_dpi_dual_edge(struct mtk_dpi *dpi)
> +{
> + if (dpi->conf->num_output_fmts > 1) {
> + mtk_dpi_mask(dpi, DPI_DDR_SETTING, DDR_EN | DDR_4PHASE,
> + DDR_EN | DDR_4PHASE);
> + mtk_dpi_mask(dpi, DPI_OUTPUT_SETTING,
> + dpi->ddr_edge_sel ? EDGE_SEL : 0, EDGE_SEL);
> + }

if (dpi->output_fmt == MEDIA_BUS_FMT_RGB888_2X12_LE) ||
(dpi->output_fmt == MEDIA_BUS_FMT_RGB888_2X12_BE) {
mtk_dpi_mask(dpi, DPI_DDR_SETTING, DDR_EN | DDR_4PHASE, DDR_EN |
DDR_4PHASE);
mtk_dpi_mask(dpi, DPI_OUTPUT_SETTING,
dpi->output_fmt ==
MEDIA_BUS_FMT_RGB888_2X12_LE ? EDGE_SEL : 0, EDGE_SEL);
} else {
mtk_dpi_mask(dpi, DPI_DDR_SETTING, DDR_EN | DDR_4PHASE, 0);
}

> +}
> +
> static void mtk_dpi_power_off(struct mtk_dpi *dpi)
> {
> if (WARN_ON(dpi->refcount == 0))
> @@ -455,7 +468,8 @@ static int mtk_dpi_set_display_mode(struct mtk_dpi *dpi,
> pll_rate = clk_get_rate(dpi->tvd_clk);
>
> vm.pixelclock = pll_rate / factor;
> - clk_set_rate(dpi->pixel_clk, vm.pixelclock);
> + clk_set_rate(dpi->pixel_clk,
> + vm.pixelclock * ((dpi->conf->num_output_fmts > 1) ? 2 : 1));

if (dpi->output_fmt == MEDIA_BUS_FMT_RGB888_2X12_LE) ||
(dpi->output_fmt == MEDIA_BUS_FMT_RGB888_2X12_BE)
clk_set_rate(dpi->pixel_clk, vm.pixelclock * 2);
else
clk_set_rate(dpi->pixel_clk, vm.pixelclock);

> vm.pixelclock = clk_get_rate(dpi->pixel_clk);
>
> dev_dbg(dpi->dev, "Got PLL %lu Hz, pixel clock %lu Hz\n",
> @@ -519,6 +533,7 @@ static int mtk_dpi_set_display_mode(struct mtk_dpi *dpi,
> mtk_dpi_config_yc_map(dpi, dpi->yc_map);
> mtk_dpi_config_color_format(dpi, dpi->color_format);
> mtk_dpi_config_2n_h_fre(dpi);
> + mtk_dpi_dual_edge(dpi);
> mtk_dpi_config_disable_edge(dpi);
> mtk_dpi_sw_reset(dpi, false);
>
> --
> 2.18.0
>