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[PATCH v1 4/5] gpu/drm: tegra: dsi: add support for Tegra20/Tegra30

Svyatoslav Ryhel posted 5 patches 2 months, 3 weeks ago
There is a newer version of this series
[PATCH v1 4/5] gpu/drm: tegra: dsi: add support for Tegra20/Tegra30
Posted by Svyatoslav Ryhel 2 months, 3 weeks ago 
Tegra20/Tegra30 are fully compatible with existing tegra DSI driver apart
clock configuration and MIPI calibration which are addressed by this patch.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 drivers/gpu/drm/tegra/drm.c |  2 ++
 drivers/gpu/drm/tegra/dsi.c | 69 ++++++++++++++++++++++---------------
 drivers/gpu/drm/tegra/dsi.h | 10 ++++++
 3 files changed, 54 insertions(+), 27 deletions(-)

diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index 4596073fe28f..5d64cd57e764 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -1359,10 +1359,12 @@ static SIMPLE_DEV_PM_OPS(host1x_drm_pm_ops, host1x_drm_suspend,
 
 static const struct of_device_id host1x_drm_subdevs[] = {
 	{ .compatible = "nvidia,tegra20-dc", },
+	{ .compatible = "nvidia,tegra20-dsi", },
 	{ .compatible = "nvidia,tegra20-hdmi", },
 	{ .compatible = "nvidia,tegra20-gr2d", },
 	{ .compatible = "nvidia,tegra20-gr3d", },
 	{ .compatible = "nvidia,tegra30-dc", },
+	{ .compatible = "nvidia,tegra30-dsi", },
 	{ .compatible = "nvidia,tegra30-hdmi", },
 	{ .compatible = "nvidia,tegra30-gr2d", },
 	{ .compatible = "nvidia,tegra30-gr3d", },
diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
index 3f91a24ebef2..85bcb8bee1ae 100644
--- a/drivers/gpu/drm/tegra/dsi.c
+++ b/drivers/gpu/drm/tegra/dsi.c
@@ -662,39 +662,48 @@ static int tegra_dsi_pad_enable(struct tegra_dsi *dsi)
 {
 	u32 value;
 
-	value = DSI_PAD_CONTROL_VS1_PULLDN(0) | DSI_PAD_CONTROL_VS1_PDIO(0);
-	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
+	/* Tegra20/30 uses DSIv0 while Tegra114+ uses DSIv1 */
+	if (of_device_is_compatible(dsi->dev->of_node, "nvidia,tegra20-dsi") ||
+	    of_device_is_compatible(dsi->dev->of_node, "nvidia,tegra30-dsi")) {
+		value = DSI_PAD_CONTROL_LPUPADJ(0x1) | DSI_PAD_CONTROL_LPDNADJ(0x1) |
+			DSI_PAD_CONTROL_PREEMP_EN(0x1) | DSI_PAD_CONTROL_SLEWDNADJ(0x6) |
+			DSI_PAD_CONTROL_SLEWUPADJ(0x6) | DSI_PAD_CONTROL_PDIO(0) |
+			DSI_PAD_CONTROL_PDIO_CLK(0) | DSI_PAD_CONTROL_PULLDN_ENAB(0);
+		tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
+	} else {
+		/*
+		 * XXX Is this still needed? The module reset is deasserted right
+		 * before this function is called.
+		 */
+		tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_0);
+		tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_1);
+		tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_2);
+		tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_3);
+		tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_4);
+
+		value = DSI_PAD_CONTROL_VS1_PULLDN(0) | DSI_PAD_CONTROL_VS1_PDIO(0);
+		tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
+
+		value = DSI_PAD_SLEW_UP(0x7) | DSI_PAD_SLEW_DN(0x7) |
+			DSI_PAD_LP_UP(0x1) | DSI_PAD_LP_DN(0x1) |
+			DSI_PAD_OUT_CLK(0x0);
+		tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_2);
+
+		value = DSI_PAD_PREEMP_PD_CLK(0x3) | DSI_PAD_PREEMP_PU_CLK(0x3) |
+			DSI_PAD_PREEMP_PD(0x03) | DSI_PAD_PREEMP_PU(0x3);
+		tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_3);
+	}
 
 	return 0;
 }
 
 static int tegra_dsi_pad_calibrate(struct tegra_dsi *dsi)
 {
-	u32 value;
 	int err;
 
-	/*
-	 * XXX Is this still needed? The module reset is deasserted right
-	 * before this function is called.
-	 */
-	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_0);
-	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_1);
-	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_2);
-	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_3);
-	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_4);
-
 	/* start calibration */
 	tegra_dsi_pad_enable(dsi);
 
-	value = DSI_PAD_SLEW_UP(0x7) | DSI_PAD_SLEW_DN(0x7) |
-		DSI_PAD_LP_UP(0x1) | DSI_PAD_LP_DN(0x1) |
-		DSI_PAD_OUT_CLK(0x0);
-	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_2);
-
-	value = DSI_PAD_PREEMP_PD_CLK(0x3) | DSI_PAD_PREEMP_PU_CLK(0x3) |
-		DSI_PAD_PREEMP_PD(0x03) | DSI_PAD_PREEMP_PU(0x3);
-	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_3);
-
 	err = tegra_mipi_start_calibration(dsi->mipi);
 	if (err < 0)
 		return err;
@@ -1615,7 +1624,7 @@ static int tegra_dsi_probe(struct platform_device *pdev)
 		goto remove;
 	}
 
-	dsi->clk_lp = devm_clk_get(&pdev->dev, "lp");
+	dsi->clk_lp = devm_clk_get_optional(&pdev->dev, "lp");
 	if (IS_ERR(dsi->clk_lp)) {
 		err = dev_err_probe(&pdev->dev, PTR_ERR(dsi->clk_lp),
 				    "cannot get low-power clock\n");
@@ -1636,10 +1645,14 @@ static int tegra_dsi_probe(struct platform_device *pdev)
 		goto remove;
 	}
 
-	err = tegra_dsi_setup_clocks(dsi);
-	if (err < 0) {
-		dev_err(&pdev->dev, "cannot setup clocks\n");
-		goto remove;
+	/* Tegra20/Tegra30 do not use DSI parent muxing */
+	if (!of_device_is_compatible(dsi->dev->of_node, "nvidia,tegra20-dsi") &&
+	    !of_device_is_compatible(dsi->dev->of_node, "nvidia,tegra30-dsi")) {
+		err = tegra_dsi_setup_clocks(dsi);
+		if (err < 0) {
+			dev_err(&pdev->dev, "cannot setup clocks\n");
+			return err;
+		}
 	}
 
 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1709,6 +1722,8 @@ static const struct of_device_id tegra_dsi_of_match[] = {
 	{ .compatible = "nvidia,tegra132-dsi", },
 	{ .compatible = "nvidia,tegra124-dsi", },
 	{ .compatible = "nvidia,tegra114-dsi", },
+	{ .compatible = "nvidia,tegra30-dsi", },
+	{ .compatible = "nvidia,tegra20-dsi", },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, tegra_dsi_of_match);
diff --git a/drivers/gpu/drm/tegra/dsi.h b/drivers/gpu/drm/tegra/dsi.h
index f39594e65e97..d834ac0c47ab 100644
--- a/drivers/gpu/drm/tegra/dsi.h
+++ b/drivers/gpu/drm/tegra/dsi.h
@@ -95,6 +95,16 @@
 #define DSI_TALLY_LRX(x)		(((x) & 0xff) <<  8)
 #define DSI_TALLY_HTX(x)		(((x) & 0xff) <<  0)
 #define DSI_PAD_CONTROL_0		0x4b
+/* Tegra20/Tegra30 */
+#define DSI_PAD_CONTROL_PULLDN_ENAB(x)	(((x) & 0x1) << 28)
+#define DSI_PAD_CONTROL_SLEWUPADJ(x)	(((x) & 0x7) << 24)
+#define DSI_PAD_CONTROL_SLEWDNADJ(x)	(((x) & 0x7) << 20)
+#define DSI_PAD_CONTROL_PREEMP_EN(x)	(((x) & 0x1) << 19)
+#define DSI_PAD_CONTROL_PDIO_CLK(x)	(((x) & 0x1) << 18)
+#define DSI_PAD_CONTROL_PDIO(x)		(((x) & 0x3) << 16)
+#define DSI_PAD_CONTROL_LPUPADJ(x)	(((x) & 0x3) << 14)
+#define DSI_PAD_CONTROL_LPDNADJ(x)	(((x) & 0x3) << 12)
+/* Tegra114+ */
 #define DSI_PAD_CONTROL_VS1_PDIO(x)	(((x) & 0xf) <<  0)
 #define DSI_PAD_CONTROL_VS1_PDIO_CLK	(1 <<  8)
 #define DSI_PAD_CONTROL_VS1_PULLDN(x)	(((x) & 0xf) << 16)
-- 
2.48.1
Re: [PATCH v1 4/5] gpu/drm: tegra: dsi: add support for Tegra20/Tegra30
Posted by Mikko Perttunen 2 months, 2 weeks ago 
On Thursday, July 17, 2025 11:21 PM Svyatoslav Ryhel wrote:
> Tegra20/Tegra30 are fully compatible with existing tegra DSI driver apart

'apart from'

> clock configuration and MIPI calibration which are addressed by this patch.
> 
> Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> ---
>  drivers/gpu/drm/tegra/drm.c |  2 ++
>  drivers/gpu/drm/tegra/dsi.c | 69 ++++++++++++++++++++++---------------
>  drivers/gpu/drm/tegra/dsi.h | 10 ++++++
>  3 files changed, 54 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
> index 4596073fe28f..5d64cd57e764 100644
> --- a/drivers/gpu/drm/tegra/drm.c
> +++ b/drivers/gpu/drm/tegra/drm.c
> @@ -1359,10 +1359,12 @@ static SIMPLE_DEV_PM_OPS(host1x_drm_pm_ops,
> host1x_drm_suspend,
> 
>  static const struct of_device_id host1x_drm_subdevs[] = {
>  	{ .compatible = "nvidia,tegra20-dc", },
> +	{ .compatible = "nvidia,tegra20-dsi", },
>  	{ .compatible = "nvidia,tegra20-hdmi", },
>  	{ .compatible = "nvidia,tegra20-gr2d", },
>  	{ .compatible = "nvidia,tegra20-gr3d", },
>  	{ .compatible = "nvidia,tegra30-dc", },
> +	{ .compatible = "nvidia,tegra30-dsi", },
>  	{ .compatible = "nvidia,tegra30-hdmi", },
>  	{ .compatible = "nvidia,tegra30-gr2d", },
>  	{ .compatible = "nvidia,tegra30-gr3d", },
> diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
> index 3f91a24ebef2..85bcb8bee1ae 100644
> --- a/drivers/gpu/drm/tegra/dsi.c
> +++ b/drivers/gpu/drm/tegra/dsi.c
> @@ -662,39 +662,48 @@ static int tegra_dsi_pad_enable(struct tegra_dsi *dsi)
> {
>  	u32 value;
> 
> -	value = DSI_PAD_CONTROL_VS1_PULLDN(0) | DSI_PAD_CONTROL_VS1_PDIO(0);
> -	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
> +	/* Tegra20/30 uses DSIv0 while Tegra114+ uses DSIv1 */
> +	if (of_device_is_compatible(dsi->dev->of_node, "nvidia,tegra20-dsi") 
||
> +	    of_device_is_compatible(dsi->dev->of_node, "nvidia,tegra30-dsi"))

You need to add "soc data" structures to the of_match table instead of 
checking for compatible string in the code itself.

Thanks,
Mikko
Re: [PATCH v1 4/5] gpu/drm: tegra: dsi: add support for Tegra20/Tegra30
Posted by Svyatoslav Ryhel 2 months, 2 weeks ago 
пт, 18 лип. 2025 р. о 12:15 Mikko Perttunen <mperttunen@nvidia.com> пише:
>
> On Thursday, July 17, 2025 11:21 PM Svyatoslav Ryhel wrote:
> > Tegra20/Tegra30 are fully compatible with existing tegra DSI driver apart
>
> 'apart from'
>
> > clock configuration and MIPI calibration which are addressed by this patch.
> >
> > Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> > ---
> >  drivers/gpu/drm/tegra/drm.c |  2 ++
> >  drivers/gpu/drm/tegra/dsi.c | 69 ++++++++++++++++++++++---------------
> >  drivers/gpu/drm/tegra/dsi.h | 10 ++++++
> >  3 files changed, 54 insertions(+), 27 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
> > index 4596073fe28f..5d64cd57e764 100644
> > --- a/drivers/gpu/drm/tegra/drm.c
> > +++ b/drivers/gpu/drm/tegra/drm.c
> > @@ -1359,10 +1359,12 @@ static SIMPLE_DEV_PM_OPS(host1x_drm_pm_ops,
> > host1x_drm_suspend,
> >
> >  static const struct of_device_id host1x_drm_subdevs[] = {
> >       { .compatible = "nvidia,tegra20-dc", },
> > +     { .compatible = "nvidia,tegra20-dsi", },
> >       { .compatible = "nvidia,tegra20-hdmi", },
> >       { .compatible = "nvidia,tegra20-gr2d", },
> >       { .compatible = "nvidia,tegra20-gr3d", },
> >       { .compatible = "nvidia,tegra30-dc", },
> > +     { .compatible = "nvidia,tegra30-dsi", },
> >       { .compatible = "nvidia,tegra30-hdmi", },
> >       { .compatible = "nvidia,tegra30-gr2d", },
> >       { .compatible = "nvidia,tegra30-gr3d", },
> > diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
> > index 3f91a24ebef2..85bcb8bee1ae 100644
> > --- a/drivers/gpu/drm/tegra/dsi.c
> > +++ b/drivers/gpu/drm/tegra/dsi.c
> > @@ -662,39 +662,48 @@ static int tegra_dsi_pad_enable(struct tegra_dsi *dsi)
> > {
> >       u32 value;
> >
> > -     value = DSI_PAD_CONTROL_VS1_PULLDN(0) | DSI_PAD_CONTROL_VS1_PDIO(0);
> > -     tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
> > +     /* Tegra20/30 uses DSIv0 while Tegra114+ uses DSIv1 */
> > +     if (of_device_is_compatible(dsi->dev->of_node, "nvidia,tegra20-dsi")
> ||
> > +         of_device_is_compatible(dsi->dev->of_node, "nvidia,tegra30-dsi"))
>
> You need to add "soc data" structures to the of_match table instead of
> checking for compatible string in the code itself.
>

I assumed that introducing "soc data" for 2 occurrences would be excessive.

> Thanks,
> Mikko
>
>
>
>

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