[PATCH v8 3/3] drm: rcar-du: rzg2l_mipi_dsi: Enhance device lanes check
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Sat Oct 15 15:51:31 UTC 2022
Hi Biju,
Thank you for the patch.
On Tue, Sep 20, 2022 at 11:55:01AM +0100, Biju Das wrote:
> Enhance device lanes check by reading TXSETR register at probe(),
> and enforced in rzg2l_mipi_dsi_host_attach().
>
> As per HW manual, we can read TXSETR register only after
> DPHY initialization.
>
> Suggested-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Signed-off-by: Biju Das <biju.das.jz at bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> ---
> v8:
> * New patch.
> ---
> drivers/gpu/drm/rcar-du/rzg2l_mipi_dsi.c | 122 ++++++++++++++++-------
> 1 file changed, 88 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/gpu/drm/rcar-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/rcar-du/rzg2l_mipi_dsi.c
> index 8579208db218..aa95b85a2964 100644
> --- a/drivers/gpu/drm/rcar-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/rcar-du/rzg2l_mipi_dsi.c
> @@ -171,6 +171,11 @@ static void rzg2l_mipi_dsi_link_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 d
> iowrite32(data, dsi->mmio + LINK_REG_OFFSET + reg);
> }
>
> +static u32 rzg2l_mipi_dsi_phy_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
> +{
> + return ioread32(dsi->mmio + reg);
> +}
> +
> static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
> {
> return ioread32(dsi->mmio + LINK_REG_OFFSET + reg);
> @@ -180,19 +185,11 @@ static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
> * Hardware Setup
> */
>
> -static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> - const struct drm_display_mode *mode)
> +static int rzg2l_mipi_dsi_dphy_init(struct rzg2l_mipi_dsi *dsi,
> + unsigned long hsfreq)
> {
> const struct rzg2l_mipi_dsi_timings *dphy_timings;
> - unsigned long hsfreq;
> - unsigned int i, bpp;
> - u32 txsetr;
> - u32 clstptsetr;
> - u32 lptrnstsetr;
> - u32 clkkpt;
> - u32 clkbfht;
> - u32 clkstpt;
> - u32 golpbkt;
> + unsigned int i;
> u32 dphyctrl0;
> u32 dphytim0;
> u32 dphytim1;
> @@ -200,19 +197,6 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> u32 dphytim3;
> int ret;
>
> - /*
> - * Relationship between hsclk and vclk must follow
> - * vclk * bpp = hsclk * 8 * lanes
> - * where vclk: video clock (Hz)
> - * bpp: video pixel bit depth
> - * hsclk: DSI HS Byte clock frequency (Hz)
> - * lanes: number of data lanes
> - *
> - * hsclk(bit) = hsclk(byte) * 8
> - */
> - bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> - hsfreq = (mode->clock * bpp * 8) / (8 * dsi->lanes);
> -
> /* All DSI global operation timings are set with recommended setting */
> for (i = 0; i < ARRAY_SIZE(rzg2l_mipi_dsi_global_timings); ++i) {
> dphy_timings = &rzg2l_mipi_dsi_global_timings[i];
> @@ -220,12 +204,6 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> break;
> }
>
> - ret = pm_runtime_resume_and_get(dsi->dev);
> - if (ret < 0)
> - return ret;
> -
> - clk_set_rate(dsi->vclk, mode->clock * 1000);
> -
> /* Initializing DPHY before accessing LINK */
> dphyctrl0 = DSIDPHYCTRL0_CAL_EN_HSRX_OFS | DSIDPHYCTRL0_CMN_MASTER_EN |
> DSIDPHYCTRL0_RE_VDD_DETVCCQLV18 | DSIDPHYCTRL0_EN_BGR;
> @@ -259,10 +237,62 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>
> ret = reset_control_deassert(dsi->rstc);
> if (ret < 0)
> - goto err_pm_put;
> + return ret;
>
> udelay(1);
>
> + return 0;
> +}
> +
> +static void rzg2l_mipi_dsi_dphy_exit(struct rzg2l_mipi_dsi *dsi)
> +{
> + u32 dphyctrl0;
> +
> + dphyctrl0 = rzg2l_mipi_dsi_phy_read(dsi, DSIDPHYCTRL0);
> +
> + dphyctrl0 &= ~(DSIDPHYCTRL0_EN_LDO1200 | DSIDPHYCTRL0_EN_BGR);
> + rzg2l_mipi_dsi_phy_write(dsi, DSIDPHYCTRL0, dphyctrl0);
> +
> + reset_control_assert(dsi->rstc);
> +}
> +
> +static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> + const struct drm_display_mode *mode)
> +{
> + unsigned long hsfreq;
> + unsigned int bpp;
> + u32 txsetr;
> + u32 clstptsetr;
> + u32 lptrnstsetr;
> + u32 clkkpt;
> + u32 clkbfht;
> + u32 clkstpt;
> + u32 golpbkt;
> + int ret;
> +
> + /*
> + * Relationship between hsclk and vclk must follow
> + * vclk * bpp = hsclk * 8 * lanes
> + * where vclk: video clock (Hz)
> + * bpp: video pixel bit depth
> + * hsclk: DSI HS Byte clock frequency (Hz)
> + * lanes: number of data lanes
> + *
> + * hsclk(bit) = hsclk(byte) * 8
> + */
> + bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> + hsfreq = (mode->clock * bpp * 8) / (8 * dsi->lanes);
> +
> + ret = pm_runtime_resume_and_get(dsi->dev);
> + if (ret < 0)
> + return ret;
> +
> + clk_set_rate(dsi->vclk, mode->clock * 1000);
> +
> + ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
> + if (ret < 0)
> + goto err_phy;
> +
> /* Enable Data lanes and Clock lanes */
> txsetr = TXSETR_DLEN | TXSETR_NUMLANEUSE(dsi->lanes - 1) | TXSETR_CLEN;
> rzg2l_mipi_dsi_link_write(dsi, TXSETR, txsetr);
> @@ -301,7 +331,8 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>
> return 0;
>
> -err_pm_put:
> +err_phy:
> + rzg2l_mipi_dsi_dphy_exit(dsi);
> pm_runtime_put(dsi->dev);
>
> return ret;
> @@ -309,7 +340,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>
> static void rzg2l_mipi_dsi_stop(struct rzg2l_mipi_dsi *dsi)
> {
> - reset_control_assert(dsi->rstc);
> + rzg2l_mipi_dsi_dphy_exit(dsi);
> pm_runtime_put(dsi->dev);
> }
>
> @@ -666,7 +697,9 @@ static const struct dev_pm_ops rzg2l_mipi_pm_ops = {
>
> static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
> {
> + unsigned int num_data_lanes;
> struct rzg2l_mipi_dsi *dsi;
> + u32 txsetr;
> int ret;
>
> dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
> @@ -681,7 +714,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
> return dev_err_probe(dsi->dev, ret,
> "missing or invalid data-lanes property\n");
>
> - dsi->num_data_lanes = ret;
> + num_data_lanes = ret;
>
> dsi->mmio = devm_platform_ioremap_resource(pdev, 0);
> if (IS_ERR(dsi->mmio))
> @@ -710,6 +743,24 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>
> pm_runtime_enable(dsi->dev);
>
> + ret = pm_runtime_resume_and_get(dsi->dev);
> + if (ret < 0)
> + goto err_pm_disable;
> +
> + /*
> + * TXSETR register can be read only after DPHY init. But during probe
> + * mode->clock and format are not available. So initialize DPHY with
> + * timing parameters for 80Mbps.
> + */
> + ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000);
> + if (ret < 0)
> + goto err_phy;
> +
> + txsetr = rzg2l_mipi_dsi_link_read(dsi, TXSETR);
> + dsi->num_data_lanes = min(((txsetr >> 16) & 3) + 1, num_data_lanes);
> + rzg2l_mipi_dsi_dphy_exit(dsi);
> + pm_runtime_put(dsi->dev);
> +
> /* Initialize the DRM bridge. */
> dsi->bridge.funcs = &rzg2l_mipi_dsi_bridge_ops;
> dsi->bridge.of_node = dsi->dev->of_node;
> @@ -723,6 +774,9 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>
> return 0;
>
> +err_phy:
> + rzg2l_mipi_dsi_dphy_exit(dsi);
> + pm_runtime_put(dsi->dev);
> err_pm_disable:
> pm_runtime_disable(dsi->dev);
> return ret;
--
Regards,
Laurent Pinchart
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