[PATCH v5 00/12] Add DU support for RZ/V2H(P) SoC

[PATCH v5 00/12] Add DU support for RZ/V2H(P) SoC

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Hi All,

This patch series adds support for the Display Unit (DU) and prepares
the MIPI DSI driver to support the Renesas RZ/V2H(P) SoC. These patches
were originally part of series [0], but I have split them into two parts
to make them easier to review and merge.

This patch series does not have any clock dependencies, so it can be
merged independently via the DU tree. The remaining patches from series
[0] will be sent as a follow-up series, which can be merged via the
Clock/DU tree as they have dependencies on the clock driver.

[0] https://lore.kernel.org/all/20250430204112.342123-1-prabhakar.mahadev-lad.rj@bp.renesas.com/

v4->v5:
- Split up the series
- Added Reviewed-by tag from Biju
- Dropped feature flags for reset and LPCLK
- Patch 07/12 is new.

v3->v4:
- Corrected parameter name in rzv2h_dsi_get_pll_parameters_values()
  description freq_millihz
- Used MILLI instead of KILO
- Made use of mul_u32_u32() for multiplication
- In rzv2h_dphy_find_ulpsexit() made the array static const.

v2->v3:
- Update the commit message for patch 1/15 to clarify the purpose
  of `renesas-rzv2h-dsi.h` header
- Used mul_u32_u32() in rzv2h_cpg_plldsi_div_determine_rate()
- Replaced *_mhz to *_millihz for clarity
- Updated u64->u32 for fvco limits
- Initialized the members in declaration order for
  RZV2H_CPG_PLL_DSI_LIMITS() macro
- Used clk_div_mask() in rzv2h_cpg_plldsi_div_recalc_rate()
- Replaced `unsigned long long` with u64
- Dropped rzv2h_cpg_plldsi_clk_recalc_rate() and reused
  rzv2h_cpg_pll_clk_recalc_rate() instead
- In rzv2h_cpg_plldsi_div_set_rate() followed the same style
  of RMW-operation as done in the other functions
- Renamed rzv2h_cpg_plldsi_set_rate() to rzv2h_cpg_pll_set_rate()
- Dropped rzv2h_cpg_plldsi_clk_register() and reused
  rzv2h_cpg_pll_clk_register() instead
- Added a guard in renesas-rzv2h-dsi.h header
- Reverted CSDIV0_DIVCTL2() to use DDIV_PACK()
- Renamed plleth_lpclk_div4 -> cdiv4_plleth_lpclk
- Renamed plleth_lpclk -> plleth_lpclk_gear
- Collected reviewed tag from Krzysztof for patch 3/15
- Dropped !dsi->info check in rzg2l_mipi_dsi_probe() as it
  is not needed.
- Simplified V2H DSI timings array to save space
- Switched to use fsleep() instead of udelay()

v1->v2:
- Rebased the changes on top of v6.15-rc1
- Kept the sort order for schema validation
- Added  `port@1: false` for RZ/V2H(P) SoC
- Added enum for RZ/V2H as suggested by Krzysztof as the list
  will grow in the future (while adding RZ/G3E SoC).
- Added Reviewed-by tag from Biju and Krzysztof.
- Replaced individual flags as reset flag
- Dropped unused macros
- Added missing LPCLK flag to rzvv2h info
- Dropped FCP and VSP documentation patch and sent them separately

Cheers,
Prabhakar

Lad Prabhakar (12):
  dt-bindings: display: renesas,rzg2l-du: Add support for RZ/V2H(P) SoC
  drm: renesas: rz-du: Add support for RZ/V2H(P) SoC
  drm: renesas: rz-du: mipi_dsi: Add min check for VCLK range
  drm: renesas: rz-du: mipi_dsi: Simplify HSFREQ calculation
  drm: renesas: rz-du: mipi_dsi: Use VCLK for HSFREQ calculation
  drm: renesas: rz-du: mipi_dsi: Add OF data support
  drm: renesas: rz-du: mipi_dsi: Make "rst" reset control optional for
    RZ/V2H(P)
  drm: renesas: rz-du: mipi_dsi: Use mHz for D-PHY frequency
    calculations
  drm: renesas: rz-du: mipi_dsi: Add feature flag for 16BPP support
  drm: renesas: rz-du: mipi_dsi: Add dphy_late_init() callback for
    RZ/V2H(P)
  drm: renesas: rz-du: mipi_dsi: Add function pointers for configuring
    VCLK and mode validation
  drm: renesas: rz-du: mipi_dsi: Add support for LPCLK clock handling

 .../bindings/display/renesas,rzg2l-du.yaml    |  23 ++-
 drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c  |  11 ++
 .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 144 ++++++++++++++----
 .../drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h   |   2 -
 4 files changed, 146 insertions(+), 34 deletions(-)

-- 
2.49.0

[PATCH v5 01/12] dt-bindings: display: renesas, rzg2l-du: Add support for RZ/V2H(P) SoC

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

The DU block on the RZ/V2H(P) SoC is identical to the one found on the
RZ/G2L SoC. However, it only supports the DSI interface, whereas the
RZ/G2L supports both DSI and DPI interfaces.

Due to this difference, a SoC-specific compatible string
'renesas,r9a09g057-du' is added for the RZ/V2H(P) SoC.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Added reviewed tag from Biju

v3->v4:
- No changes

v2->v3:
- Collected reviewed tag from Krzysztof

v1->v2:
- Kept the sort order for schema validation
- Added  `port@1: false` for RZ/V2H(P) SoC
---
 .../bindings/display/renesas,rzg2l-du.yaml    | 23 ++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/display/renesas,rzg2l-du.yaml b/Documentation/devicetree/bindings/display/renesas,rzg2l-du.yaml
index 95e3d5e74b87..1e32d14b6edb 100644
--- a/Documentation/devicetree/bindings/display/renesas,rzg2l-du.yaml
+++ b/Documentation/devicetree/bindings/display/renesas,rzg2l-du.yaml
@@ -20,6 +20,7 @@ properties:
       - enum:
           - renesas,r9a07g043u-du # RZ/G2UL
           - renesas,r9a07g044-du # RZ/G2{L,LC}
+          - renesas,r9a09g057-du # RZ/V2H(P)
       - items:
           - enum:
               - renesas,r9a07g054-du    # RZ/V2L
@@ -101,7 +102,12 @@ allOf:
 
           required:
             - port@0
-    else:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: renesas,r9a07g044-du
+    then:
       properties:
         ports:
           properties:
@@ -113,6 +119,21 @@ allOf:
           required:
             - port@0
             - port@1
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: renesas,r9a09g057-du
+    then:
+      properties:
+        ports:
+          properties:
+            port@0:
+              description: DSI
+            port@1: false
+
+          required:
+            - port@0
 
 examples:
   # RZ/G2L DU
-- 
2.49.0

Re: [PATCH v5 01/12] dt-bindings: display: renesas,rzg2l-du: Add support for RZ/V2H(P) SoC

[Laurent Pinchart]

Hi Prabhakar,

Thank you for the patch.

On Mon, May 12, 2025 at 07:23:19PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> The DU block on the RZ/V2H(P) SoC is identical to the one found on the
> RZ/G2L SoC. However, it only supports the DSI interface, whereas the
> RZ/G2L supports both DSI and DPI interfaces.
> 
> Due to this difference, a SoC-specific compatible string
> 'renesas,r9a09g057-du' is added for the RZ/V2H(P) SoC.
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> ---
> v4->v5:
> - Added reviewed tag from Biju
> 
> v3->v4:
> - No changes
> 
> v2->v3:
> - Collected reviewed tag from Krzysztof
> 
> v1->v2:
> - Kept the sort order for schema validation
> - Added  `port@1: false` for RZ/V2H(P) SoC
> ---
>  .../bindings/display/renesas,rzg2l-du.yaml    | 23 ++++++++++++++++++-
>  1 file changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/renesas,rzg2l-du.yaml b/Documentation/devicetree/bindings/display/renesas,rzg2l-du.yaml
> index 95e3d5e74b87..1e32d14b6edb 100644
> --- a/Documentation/devicetree/bindings/display/renesas,rzg2l-du.yaml
> +++ b/Documentation/devicetree/bindings/display/renesas,rzg2l-du.yaml
> @@ -20,6 +20,7 @@ properties:
>        - enum:
>            - renesas,r9a07g043u-du # RZ/G2UL
>            - renesas,r9a07g044-du # RZ/G2{L,LC}
> +          - renesas,r9a09g057-du # RZ/V2H(P)
>        - items:
>            - enum:
>                - renesas,r9a07g054-du    # RZ/V2L
> @@ -101,7 +102,12 @@ allOf:
>  
>            required:
>              - port@0
> -    else:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: renesas,r9a07g044-du
> +    then:
>        properties:
>          ports:
>            properties:
> @@ -113,6 +119,21 @@ allOf:
>            required:
>              - port@0
>              - port@1
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: renesas,r9a09g057-du
> +    then:
> +      properties:
> +        ports:
> +          properties:
> +            port@0:
> +              description: DSI
> +            port@1: false
> +
> +          required:
> +            - port@0
>  
>  examples:
>    # RZ/G2L DU

-- 
Regards,

Laurent Pinchart

[PATCH v5 02/12] drm: renesas: rz-du: Add support for RZ/V2H(P) SoC

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

The LCD controller (LCDC) on the RZ/V2H(P) SoC is composed of Frame
Compression Processor (FCPVD), Video Signal Processor (VSPD), and
Display Unit (DU).

There is one LCDC unit available on the RZ/V2H(P) SoC which is connected
to the DSI.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Added reviewed tag from Biju

v3->v4:
- No changes

v2->v3:
- No changes

v1->v2:
- No changes
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c
index 5e40f0c1e7b0..e1aa6a719529 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c
@@ -50,9 +50,20 @@ static const struct rzg2l_du_device_info rzg2l_du_r9a07g044_info = {
 	}
 };
 
+static const struct rzg2l_du_device_info rzg2l_du_r9a09g057_info = {
+	.channels_mask = BIT(0),
+	.routes = {
+		[RZG2L_DU_OUTPUT_DSI0] = {
+			.possible_outputs = BIT(0),
+			.port = 0,
+		},
+	},
+};
+
 static const struct of_device_id rzg2l_du_of_table[] = {
 	{ .compatible = "renesas,r9a07g043u-du", .data = &rzg2l_du_r9a07g043u_info },
 	{ .compatible = "renesas,r9a07g044-du", .data = &rzg2l_du_r9a07g044_info },
+	{ .compatible = "renesas,r9a09g057-du", .data = &rzg2l_du_r9a09g057_info },
 	{ /* sentinel */ }
 };
 
-- 
2.49.0

Re: [PATCH v5 02/12] drm: renesas: rz-du: Add support for RZ/V2H(P) SoC

[Laurent Pinchart]

Hi Prabhakar,

Thank you for the patch.

On Mon, May 12, 2025 at 07:23:20PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> The LCD controller (LCDC) on the RZ/V2H(P) SoC is composed of Frame
> Compression Processor (FCPVD), Video Signal Processor (VSPD), and
> Display Unit (DU).
> 
> There is one LCDC unit available on the RZ/V2H(P) SoC which is connected
> to the DSI.
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> ---
> v4->v5:
> - Added reviewed tag from Biju
> 
> v3->v4:
> - No changes
> 
> v2->v3:
> - No changes
> 
> v1->v2:
> - No changes
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c
> index 5e40f0c1e7b0..e1aa6a719529 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_du_drv.c
> @@ -50,9 +50,20 @@ static const struct rzg2l_du_device_info rzg2l_du_r9a07g044_info = {
>  	}
>  };
>  
> +static const struct rzg2l_du_device_info rzg2l_du_r9a09g057_info = {
> +	.channels_mask = BIT(0),
> +	.routes = {
> +		[RZG2L_DU_OUTPUT_DSI0] = {
> +			.possible_outputs = BIT(0),
> +			.port = 0,
> +		},
> +	},
> +};
> +
>  static const struct of_device_id rzg2l_du_of_table[] = {
>  	{ .compatible = "renesas,r9a07g043u-du", .data = &rzg2l_du_r9a07g043u_info },
>  	{ .compatible = "renesas,r9a07g044-du", .data = &rzg2l_du_r9a07g044_info },
> +	{ .compatible = "renesas,r9a09g057-du", .data = &rzg2l_du_r9a09g057_info },
>  	{ /* sentinel */ }
>  };
>  

-- 
Regards,

Laurent Pinchart

[PATCH v5 03/12] drm: renesas: rz-du: mipi_dsi: Add min check for VCLK range

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

The VCLK range for Renesas RZ/G2L SoC is 148.5 MHz to 5.803 MHz. Add a
minimum clock check in the mode_valid callback to ensure that the clock
value does not fall below the valid range.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- No changes

v3->v4:
- No changes

v2->v3:
- No changes

v1->v2:
- Added reviewed tag from Biju 
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index 4550c6d84796..ec8baecb9ba5 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -584,6 +584,9 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
 	if (mode->clock > 148500)
 		return MODE_CLOCK_HIGH;
 
+	if (mode->clock < 5803)
+		return MODE_CLOCK_LOW;
+
 	return MODE_OK;
 }
 
-- 
2.49.0

Re: [PATCH v5 03/12] drm: renesas: rz-du: mipi_dsi: Add min check for VCLK range

[Laurent Pinchart]

Hi Prabhakar,

On Mon, May 12, 2025 at 07:23:21PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> The VCLK range for Renesas RZ/G2L SoC is 148.5 MHz to 5.803 MHz. Add a

I would write "5.803 MHz to 148.5 MHz" as ranges are usually expressed
in increasing order.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> minimum clock check in the mode_valid callback to ensure that the clock
> value does not fall below the valid range.
> 
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v4->v5:
> - No changes
> 
> v3->v4:
> - No changes
> 
> v2->v3:
> - No changes
> 
> v1->v2:
> - Added reviewed tag from Biju 
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index 4550c6d84796..ec8baecb9ba5 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -584,6 +584,9 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
>  	if (mode->clock > 148500)
>  		return MODE_CLOCK_HIGH;
>  
> +	if (mode->clock < 5803)
> +		return MODE_CLOCK_LOW;
> +
>  	return MODE_OK;
>  }
>  

-- 
Regards,

Laurent Pinchart

Re: [PATCH v5 03/12] drm: renesas: rz-du: mipi_dsi: Add min check for VCLK range

[Lad, Prabhakar]

Hi Laurent,

Thank you for the review.

On Tue, May 20, 2025 at 2:58 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hi Prabhakar,
>
> On Mon, May 12, 2025 at 07:23:21PM +0100, Prabhakar wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > The VCLK range for Renesas RZ/G2L SoC is 148.5 MHz to 5.803 MHz. Add a
>
> I would write "5.803 MHz to 148.5 MHz" as ranges are usually expressed
> in increasing order.
>
Ok, I will update the commit message as above.

Cheers,
Prabhakar

> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
>
> > minimum clock check in the mode_valid callback to ensure that the clock
> > value does not fall below the valid range.
> >
> > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> > v4->v5:
> > - No changes
> >
> > v3->v4:
> > - No changes
> >
> > v2->v3:
> > - No changes
> >
> > v1->v2:
> > - Added reviewed tag from Biju
> > ---
> >  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 3 +++
> >  1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > index 4550c6d84796..ec8baecb9ba5 100644
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > @@ -584,6 +584,9 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
> >       if (mode->clock > 148500)
> >               return MODE_CLOCK_HIGH;
> >
> > +     if (mode->clock < 5803)
> > +             return MODE_CLOCK_LOW;
> > +
> >       return MODE_OK;
> >  }
> >
>
> --
> Regards,
>
> Laurent Pinchart

[PATCH v5 04/12] drm: renesas: rz-du: mipi_dsi: Simplify HSFREQ calculation

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Simplify the high-speed clock frequency (HSFREQ) calculation by removing
the redundant multiplication and division by 8. The updated equation:

    hsfreq = (mode->clock * bpp) / (dsi->lanes);

produces the same result while improving readability and clarity.

Additionally, update the comment to clarify the relationship between HS
clock bit frequency, HS byte clock frequency, and HSFREQ.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- No changes

v3->v4:
- No changes

v2->v3:
- No changes

v1->v2:
- Added Reviewed-by tag from Biju
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index ec8baecb9ba5..c5f698cd74f1 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -277,10 +277,10 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	 *       hsclk: DSI HS Byte clock frequency (Hz)
 	 *       lanes: number of data lanes
 	 *
-	 * hsclk(bit) = hsclk(byte) * 8
+	 * hsclk(bit) = hsclk(byte) * 8 = hsfreq
 	 */
 	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
-	hsfreq = (mode->clock * bpp * 8) / (8 * dsi->lanes);
+	hsfreq = (mode->clock * bpp) / dsi->lanes;
 
 	ret = pm_runtime_resume_and_get(dsi->dev);
 	if (ret < 0)
-- 
2.49.0

Re: [PATCH v5 04/12] drm: renesas: rz-du: mipi_dsi: Simplify HSFREQ calculation

[Laurent Pinchart]

Hi Prabhakar,

Thank you for the patch.

On Mon, May 12, 2025 at 07:23:22PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> Simplify the high-speed clock frequency (HSFREQ) calculation by removing
> the redundant multiplication and division by 8. The updated equation:
> 
>     hsfreq = (mode->clock * bpp) / (dsi->lanes);

You can drop the parentheses around the second factor. You can actuall
drop all prentheses.

> 
> produces the same result while improving readability and clarity.
> 
> Additionally, update the comment to clarify the relationship between HS
> clock bit frequency, HS byte clock frequency, and HSFREQ.
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v4->v5:
> - No changes
> 
> v3->v4:
> - No changes
> 
> v2->v3:
> - No changes
> 
> v1->v2:
> - Added Reviewed-by tag from Biju
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index ec8baecb9ba5..c5f698cd74f1 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -277,10 +277,10 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  	 *       hsclk: DSI HS Byte clock frequency (Hz)
>  	 *       lanes: number of data lanes
>  	 *
> -	 * hsclk(bit) = hsclk(byte) * 8
> +	 * hsclk(bit) = hsclk(byte) * 8 = hsfreq
>  	 */
>  	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> -	hsfreq = (mode->clock * bpp * 8) / (8 * dsi->lanes);
> +	hsfreq = (mode->clock * bpp) / dsi->lanes;

You can drop the parentheses here too.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

>  
>  	ret = pm_runtime_resume_and_get(dsi->dev);
>  	if (ret < 0)

-- 
Regards,

Laurent Pinchart

Re: [PATCH v5 04/12] drm: renesas: rz-du: mipi_dsi: Simplify HSFREQ calculation

[Lad, Prabhakar]

Hi Laurent,

Thank you for the review.

On Tue, May 20, 2025 at 3:05 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hi Prabhakar,
>
> Thank you for the patch.
>
> On Mon, May 12, 2025 at 07:23:22PM +0100, Prabhakar wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Simplify the high-speed clock frequency (HSFREQ) calculation by removing
> > the redundant multiplication and division by 8. The updated equation:
> >
> >     hsfreq = (mode->clock * bpp) / (dsi->lanes);
>
> You can drop the parentheses around the second factor. You can actuall
> drop all prentheses.
>
Agreed, I will drop the parentheses.

> >
> > produces the same result while improving readability and clarity.
> >
> > Additionally, update the comment to clarify the relationship between HS
> > clock bit frequency, HS byte clock frequency, and HSFREQ.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> > v4->v5:
> > - No changes
> >
> > v3->v4:
> > - No changes
> >
> > v2->v3:
> > - No changes
> >
> > v1->v2:
> > - Added Reviewed-by tag from Biju
> > ---
> >  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > index ec8baecb9ba5..c5f698cd74f1 100644
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > @@ -277,10 +277,10 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >        *       hsclk: DSI HS Byte clock frequency (Hz)
> >        *       lanes: number of data lanes
> >        *
> > -      * hsclk(bit) = hsclk(byte) * 8
> > +      * hsclk(bit) = hsclk(byte) * 8 = hsfreq
> >        */
> >       bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> > -     hsfreq = (mode->clock * bpp * 8) / (8 * dsi->lanes);
> > +     hsfreq = (mode->clock * bpp) / dsi->lanes;
>
> You can drop the parentheses here too.
>
OK, I'll drop the parentheses.

Cheers,
Prabhakar

[PATCH v5 05/12] drm: renesas: rz-du: mipi_dsi: Use VCLK for HSFREQ calculation

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Update the RZ/G2L MIPI DSI driver to calculate HSFREQ using the actual
VCLK rate instead of the mode clock. The relationship between HSCLK and
VCLK is:

    vclk * bpp <= hsclk * 8 * lanes

Retrieve the VCLK rate using `clk_get_rate(dsi->vclk)`, ensuring that
HSFREQ accurately reflects the clock rate set in hardware, leading to
better precision in data transmission.

Additionally, use `DIV_ROUND_CLOSEST_ULL` for a more precise division
when computing `hsfreq`. Also, update unit conversions to use correct
scaling factors for better clarity and correctness.

Since `clk_get_rate()` returns the clock rate in Hz, update the HSFREQ
threshold comparisons to use Hz instead of kHz to ensure correct behavior.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Added dev_info() to print the VCLK rate if it doesn't match the
  requested rate.
- Added Reviewed-by tag from Biju

v3->v4:
- Used MILLI instead of KILO

v2->v3:
- No changes

v1->v2:
- No changes
---
 .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 30 +++++++++++--------
 1 file changed, 18 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index c5f698cd74f1..3f6988303e63 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -8,6 +8,7 @@
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
+#include <linux/math.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_graph.h>
@@ -15,6 +16,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/reset.h>
 #include <linux/slab.h>
+#include <linux/units.h>
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
@@ -199,7 +201,7 @@ static int rzg2l_mipi_dsi_dphy_init(struct rzg2l_mipi_dsi *dsi,
 	/* 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];
-		if (hsfreq <= dphy_timings->hsfreq_max)
+		if (hsfreq <= (dphy_timings->hsfreq_max * MILLI))
 			break;
 	}
 
@@ -258,7 +260,7 @@ static void rzg2l_mipi_dsi_dphy_exit(struct rzg2l_mipi_dsi *dsi)
 static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 				  const struct drm_display_mode *mode)
 {
-	unsigned long hsfreq;
+	unsigned long hsfreq, vclk_rate;
 	unsigned int bpp;
 	u32 txsetr;
 	u32 clstptsetr;
@@ -269,6 +271,12 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	u32 golpbkt;
 	int ret;
 
+	ret = pm_runtime_resume_and_get(dsi->dev);
+	if (ret < 0)
+		return ret;
+
+	clk_set_rate(dsi->vclk, mode->clock * MILLI);
+
 	/*
 	 * Relationship between hsclk and vclk must follow
 	 * vclk * bpp = hsclk * 8 * lanes
@@ -280,13 +288,11 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	 * hsclk(bit) = hsclk(byte) * 8 = hsfreq
 	 */
 	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
-	hsfreq = (mode->clock * bpp) / dsi->lanes;
-
-	ret = pm_runtime_resume_and_get(dsi->dev);
-	if (ret < 0)
-		return ret;
-
-	clk_set_rate(dsi->vclk, mode->clock * 1000);
+	vclk_rate = clk_get_rate(dsi->vclk);
+	if (vclk_rate != mode->clock * MILLI)
+		dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
+			 mode->clock * MILLI, vclk_rate);
+	hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
 
 	ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
 	if (ret < 0)
@@ -304,12 +310,12 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	 * - data lanes: maximum 4 lanes
 	 * Therefore maximum hsclk will be 891 Mbps.
 	 */
-	if (hsfreq > 445500) {
+	if (hsfreq > 445500000) {
 		clkkpt = 12;
 		clkbfht = 15;
 		clkstpt = 48;
 		golpbkt = 75;
-	} else if (hsfreq > 250000) {
+	} else if (hsfreq > 250000000) {
 		clkkpt = 7;
 		clkbfht = 8;
 		clkstpt = 27;
@@ -753,7 +759,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
 	 * mode->clock and format are not available. So initialize DPHY with
 	 * timing parameters for 80Mbps.
 	 */
-	ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000);
+	ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000000);
 	if (ret < 0)
 		goto err_phy;
 
-- 
2.49.0

Re: [PATCH v5 05/12] drm: renesas: rz-du: mipi_dsi: Use VCLK for HSFREQ calculation

[Laurent Pinchart]

Hi Prabhakar,

On Mon, May 12, 2025 at 07:23:23PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> Update the RZ/G2L MIPI DSI driver to calculate HSFREQ using the actual
> VCLK rate instead of the mode clock. The relationship between HSCLK and
> VCLK is:
> 
>     vclk * bpp <= hsclk * 8 * lanes
> 
> Retrieve the VCLK rate using `clk_get_rate(dsi->vclk)`, ensuring that
> HSFREQ accurately reflects the clock rate set in hardware, leading to
> better precision in data transmission.
> 
> Additionally, use `DIV_ROUND_CLOSEST_ULL` for a more precise division
> when computing `hsfreq`. Also, update unit conversions to use correct
> scaling factors for better clarity and correctness.
> 
> Since `clk_get_rate()` returns the clock rate in Hz, update the HSFREQ
> threshold comparisons to use Hz instead of kHz to ensure correct behavior.
> 
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v4->v5:
> - Added dev_info() to print the VCLK rate if it doesn't match the
>   requested rate.
> - Added Reviewed-by tag from Biju
> 
> v3->v4:
> - Used MILLI instead of KILO
> 
> v2->v3:
> - No changes
> 
> v1->v2:
> - No changes
> ---
>  .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 30 +++++++++++--------
>  1 file changed, 18 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index c5f698cd74f1..3f6988303e63 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -8,6 +8,7 @@
>  #include <linux/delay.h>
>  #include <linux/io.h>
>  #include <linux/iopoll.h>
> +#include <linux/math.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
>  #include <linux/of_graph.h>
> @@ -15,6 +16,7 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/reset.h>
>  #include <linux/slab.h>
> +#include <linux/units.h>
>  
>  #include <drm/drm_atomic.h>
>  #include <drm/drm_atomic_helper.h>
> @@ -199,7 +201,7 @@ static int rzg2l_mipi_dsi_dphy_init(struct rzg2l_mipi_dsi *dsi,
>  	/* 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];
> -		if (hsfreq <= dphy_timings->hsfreq_max)
> +		if (hsfreq <= (dphy_timings->hsfreq_max * MILLI))

No need for the inner parentheses.

>  			break;
>  	}
>  
> @@ -258,7 +260,7 @@ static void rzg2l_mipi_dsi_dphy_exit(struct rzg2l_mipi_dsi *dsi)
>  static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  				  const struct drm_display_mode *mode)
>  {
> -	unsigned long hsfreq;
> +	unsigned long hsfreq, vclk_rate;
>  	unsigned int bpp;
>  	u32 txsetr;
>  	u32 clstptsetr;
> @@ -269,6 +271,12 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  	u32 golpbkt;
>  	int ret;
>  
> +	ret = pm_runtime_resume_and_get(dsi->dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	clk_set_rate(dsi->vclk, mode->clock * MILLI);
> +
>  	/*
>  	 * Relationship between hsclk and vclk must follow
>  	 * vclk * bpp = hsclk * 8 * lanes
> @@ -280,13 +288,11 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  	 * hsclk(bit) = hsclk(byte) * 8 = hsfreq
>  	 */
>  	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> -	hsfreq = (mode->clock * bpp) / dsi->lanes;
> -
> -	ret = pm_runtime_resume_and_get(dsi->dev);
> -	if (ret < 0)
> -		return ret;
> -
> -	clk_set_rate(dsi->vclk, mode->clock * 1000);
> +	vclk_rate = clk_get_rate(dsi->vclk);
> +	if (vclk_rate != mode->clock * MILLI)
> +		dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
> +			 mode->clock * MILLI, vclk_rate);

There's a high risk that the requested rate won't be achieved exactly.
Do we really want to print a non-debug message to the kernel log every
time ?

> +	hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);

I doubt DIV_ROUND_CLOSEST_ULL() will make any difference in practice
given that you can't have more than 4 lanes, but that's fine.

>  
>  	ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
>  	if (ret < 0)
> @@ -304,12 +310,12 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  	 * - data lanes: maximum 4 lanes
>  	 * Therefore maximum hsclk will be 891 Mbps.
>  	 */
> -	if (hsfreq > 445500) {
> +	if (hsfreq > 445500000) {
>  		clkkpt = 12;
>  		clkbfht = 15;
>  		clkstpt = 48;
>  		golpbkt = 75;
> -	} else if (hsfreq > 250000) {
> +	} else if (hsfreq > 250000000) {
>  		clkkpt = 7;
>  		clkbfht = 8;
>  		clkstpt = 27;
> @@ -753,7 +759,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>  	 * mode->clock and format are not available. So initialize DPHY with
>  	 * timing parameters for 80Mbps.
>  	 */
> -	ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000);
> +	ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000000);
>  	if (ret < 0)
>  		goto err_phy;
>  

-- 
Regards,

Laurent Pinchart

Re: [PATCH v5 05/12] drm: renesas: rz-du: mipi_dsi: Use VCLK for HSFREQ calculation

[Lad, Prabhakar]

Hi Laurent,

Thank you for the review.

On Tue, May 20, 2025 at 3:16 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hi Prabhakar,
>
> On Mon, May 12, 2025 at 07:23:23PM +0100, Prabhakar wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Update the RZ/G2L MIPI DSI driver to calculate HSFREQ using the actual
> > VCLK rate instead of the mode clock. The relationship between HSCLK and
> > VCLK is:
> >
> >     vclk * bpp <= hsclk * 8 * lanes
> >
> > Retrieve the VCLK rate using `clk_get_rate(dsi->vclk)`, ensuring that
> > HSFREQ accurately reflects the clock rate set in hardware, leading to
> > better precision in data transmission.
> >
> > Additionally, use `DIV_ROUND_CLOSEST_ULL` for a more precise division
> > when computing `hsfreq`. Also, update unit conversions to use correct
> > scaling factors for better clarity and correctness.
> >
> > Since `clk_get_rate()` returns the clock rate in Hz, update the HSFREQ
> > threshold comparisons to use Hz instead of kHz to ensure correct behavior.
> >
> > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> > v4->v5:
> > - Added dev_info() to print the VCLK rate if it doesn't match the
> >   requested rate.
> > - Added Reviewed-by tag from Biju
> >
> > v3->v4:
> > - Used MILLI instead of KILO
> >
> > v2->v3:
> > - No changes
> >
> > v1->v2:
> > - No changes
> > ---
> >  .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 30 +++++++++++--------
> >  1 file changed, 18 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > index c5f698cd74f1..3f6988303e63 100644
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > @@ -8,6 +8,7 @@
> >  #include <linux/delay.h>
> >  #include <linux/io.h>
> >  #include <linux/iopoll.h>
> > +#include <linux/math.h>
> >  #include <linux/module.h>
> >  #include <linux/of.h>
> >  #include <linux/of_graph.h>
> > @@ -15,6 +16,7 @@
> >  #include <linux/pm_runtime.h>
> >  #include <linux/reset.h>
> >  #include <linux/slab.h>
> > +#include <linux/units.h>
> >
> >  #include <drm/drm_atomic.h>
> >  #include <drm/drm_atomic_helper.h>
> > @@ -199,7 +201,7 @@ static int rzg2l_mipi_dsi_dphy_init(struct rzg2l_mipi_dsi *dsi,
> >       /* 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];
> > -             if (hsfreq <= dphy_timings->hsfreq_max)
> > +             if (hsfreq <= (dphy_timings->hsfreq_max * MILLI))
>
> No need for the inner parentheses.
>
Agreed, I will drop it.

> >                       break;
> >       }
> >
> > @@ -258,7 +260,7 @@ static void rzg2l_mipi_dsi_dphy_exit(struct rzg2l_mipi_dsi *dsi)
> >  static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >                                 const struct drm_display_mode *mode)
> >  {
> > -     unsigned long hsfreq;
> > +     unsigned long hsfreq, vclk_rate;
> >       unsigned int bpp;
> >       u32 txsetr;
> >       u32 clstptsetr;
> > @@ -269,6 +271,12 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >       u32 golpbkt;
> >       int ret;
> >
> > +     ret = pm_runtime_resume_and_get(dsi->dev);
> > +     if (ret < 0)
> > +             return ret;
> > +
> > +     clk_set_rate(dsi->vclk, mode->clock * MILLI);
> > +
> >       /*
> >        * Relationship between hsclk and vclk must follow
> >        * vclk * bpp = hsclk * 8 * lanes
> > @@ -280,13 +288,11 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >        * hsclk(bit) = hsclk(byte) * 8 = hsfreq
> >        */
> >       bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> > -     hsfreq = (mode->clock * bpp) / dsi->lanes;
> > -
> > -     ret = pm_runtime_resume_and_get(dsi->dev);
> > -     if (ret < 0)
> > -             return ret;
> > -
> > -     clk_set_rate(dsi->vclk, mode->clock * 1000);
> > +     vclk_rate = clk_get_rate(dsi->vclk);
> > +     if (vclk_rate != mode->clock * MILLI)
> > +             dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
> > +                      mode->clock * MILLI, vclk_rate);
>
> There's a high risk that the requested rate won't be achieved exactly.
> Do we really want to print a non-debug message to the kernel log every
> time ?
>
Actually Biju requested the above.

> > +     hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
>
> I doubt DIV_ROUND_CLOSEST_ULL() will make any difference in practice
> given that you can't have more than 4 lanes, but that's fine.
>
Thanks, I'll check on it.

Cheers,
Prabhakar
> >
> >       ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
> >       if (ret < 0)
> > @@ -304,12 +310,12 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >        * - data lanes: maximum 4 lanes
> >        * Therefore maximum hsclk will be 891 Mbps.
> >        */
> > -     if (hsfreq > 445500) {
> > +     if (hsfreq > 445500000) {
> >               clkkpt = 12;
> >               clkbfht = 15;
> >               clkstpt = 48;
> >               golpbkt = 75;
> > -     } else if (hsfreq > 250000) {
> > +     } else if (hsfreq > 250000000) {
> >               clkkpt = 7;
> >               clkbfht = 8;
> >               clkstpt = 27;
> > @@ -753,7 +759,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
> >        * mode->clock and format are not available. So initialize DPHY with
> >        * timing parameters for 80Mbps.
> >        */
> > -     ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000);
> > +     ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000000);
> >       if (ret < 0)
> >               goto err_phy;
> >
>
> --
> Regards,
>
> Laurent Pinchart

RE: [PATCH v5 05/12] drm: renesas: rz-du: mipi_dsi: Use VCLK for HSFREQ calculation

[Biju Das]

> -----Original Message-----
> From: Lad, Prabhakar <prabhakar.csengg@gmail.com>
> Sent: Wednesday, May 21, 2025 2:05 PM
> Subject: Re: [PATCH v5 05/12] drm: renesas: rz-du: mipi_dsi: Use VCLK for
> HSFREQ calculation
> 
> Hi Laurent,
> 
> Thank you for the review.
> 
> On Tue, May 20, 2025 at 3:16 PM Laurent Pinchart
> <laurent.pinchart@ideasonboard.com> wrote:
> >
> > Hi Prabhakar,
> >
> > On Mon, May 12, 2025 at 07:23:23PM +0100, Prabhakar wrote:
> > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > >
> > > Update the RZ/G2L MIPI DSI driver to calculate HSFREQ using the
> > > actual VCLK rate instead of the mode clock. The relationship between
> > > HSCLK and VCLK is:
> > >
> > >     vclk * bpp <= hsclk * 8 * lanes
> > >
> > > Retrieve the VCLK rate using `clk_get_rate(dsi->vclk)`, ensuring
> > > that HSFREQ accurately reflects the clock rate set in hardware,
> > > leading to better precision in data transmission.
> > >
> > > Additionally, use `DIV_ROUND_CLOSEST_ULL` for a more precise
> > > division when computing `hsfreq`. Also, update unit conversions to
> > > use correct scaling factors for better clarity and correctness.
> > >
> > > Since `clk_get_rate()` returns the clock rate in Hz, update the
> > > HSFREQ threshold comparisons to use Hz instead of kHz to ensure
> correct behavior.
> > >
> > > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > > Signed-off-by: Lad Prabhakar
> > > <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > > ---
> > > v4->v5:
> > > - Added dev_info() to print the VCLK rate if it doesn't match the
> > >   requested rate.
> > > - Added Reviewed-by tag from Biju
> > >
> > > v3->v4:
> > > - Used MILLI instead of KILO
> > >
> > > v2->v3:
> > > - No changes
> > >
> > > v1->v2:
> > > - No changes
> > > ---
> > >  .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 30 +++++++++++-------
> -
> > >  1 file changed, 18 insertions(+), 12 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > > b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > > index c5f698cd74f1..3f6988303e63 100644
> > > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > > @@ -8,6 +8,7 @@
> > >  #include <linux/delay.h>
> > >  #include <linux/io.h>
> > >  #include <linux/iopoll.h>
> > > +#include <linux/math.h>
> > >  #include <linux/module.h>
> > >  #include <linux/of.h>
> > >  #include <linux/of_graph.h>
> > > @@ -15,6 +16,7 @@
> > >  #include <linux/pm_runtime.h>
> > >  #include <linux/reset.h>
> > >  #include <linux/slab.h>
> > > +#include <linux/units.h>
> > >
> > >  #include <drm/drm_atomic.h>
> > >  #include <drm/drm_atomic_helper.h>
> > > @@ -199,7 +201,7 @@ static int rzg2l_mipi_dsi_dphy_init(struct
> rzg2l_mipi_dsi *dsi,
> > >       /* 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];
> > > -             if (hsfreq <= dphy_timings->hsfreq_max)
> > > +             if (hsfreq <= (dphy_timings->hsfreq_max * MILLI))
> >
> > No need for the inner parentheses.
> >
> Agreed, I will drop it.
> 
> > >                       break;
> > >       }
> > >
> > > @@ -258,7 +260,7 @@ static void rzg2l_mipi_dsi_dphy_exit(struct
> > > rzg2l_mipi_dsi *dsi)  static int rzg2l_mipi_dsi_startup(struct
> rzg2l_mipi_dsi *dsi,
> > >                                 const struct drm_display_mode *mode)
> > > {
> > > -     unsigned long hsfreq;
> > > +     unsigned long hsfreq, vclk_rate;
> > >       unsigned int bpp;
> > >       u32 txsetr;
> > >       u32 clstptsetr;
> > > @@ -269,6 +271,12 @@ static int rzg2l_mipi_dsi_startup(struct
> rzg2l_mipi_dsi *dsi,
> > >       u32 golpbkt;
> > >       int ret;
> > >
> > > +     ret = pm_runtime_resume_and_get(dsi->dev);
> > > +     if (ret < 0)
> > > +             return ret;
> > > +
> > > +     clk_set_rate(dsi->vclk, mode->clock * MILLI);
> > > +
> > >       /*
> > >        * Relationship between hsclk and vclk must follow
> > >        * vclk * bpp = hsclk * 8 * lanes @@ -280,13 +288,11 @@ static
> > > int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> > >        * hsclk(bit) = hsclk(byte) * 8 = hsfreq
> > >        */
> > >       bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> > > -     hsfreq = (mode->clock * bpp) / dsi->lanes;
> > > -
> > > -     ret = pm_runtime_resume_and_get(dsi->dev);
> > > -     if (ret < 0)
> > > -             return ret;
> > > -
> > > -     clk_set_rate(dsi->vclk, mode->clock * 1000);
> > > +     vclk_rate = clk_get_rate(dsi->vclk);
> > > +     if (vclk_rate != mode->clock * MILLI)
> > > +             dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu
> mismatch\n",
> > > +                      mode->clock * MILLI, vclk_rate);
> >
> > There's a high risk that the requested rate won't be achieved exactly.
> > Do we really want to print a non-debug message to the kernel log every
> > time ?
> >
> Actually Biju requested the above.

Yes, I was looking for dev_dbg.

Cheers,
Biju

> 
> > > +     hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
> >
> > I doubt DIV_ROUND_CLOSEST_ULL() will make any difference in practice
> > given that you can't have more than 4 lanes, but that's fine.
> >
> Thanks, I'll check on it.
> 
> Cheers,
> Prabhakar
> > >
> > >       ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
> > >       if (ret < 0)
> > > @@ -304,12 +310,12 @@ static int rzg2l_mipi_dsi_startup(struct
> rzg2l_mipi_dsi *dsi,
> > >        * - data lanes: maximum 4 lanes
> > >        * Therefore maximum hsclk will be 891 Mbps.
> > >        */
> > > -     if (hsfreq > 445500) {
> > > +     if (hsfreq > 445500000) {
> > >               clkkpt = 12;
> > >               clkbfht = 15;
> > >               clkstpt = 48;
> > >               golpbkt = 75;
> > > -     } else if (hsfreq > 250000) {
> > > +     } else if (hsfreq > 250000000) {
> > >               clkkpt = 7;
> > >               clkbfht = 8;
> > >               clkstpt = 27;
> > > @@ -753,7 +759,7 @@ static int rzg2l_mipi_dsi_probe(struct
> platform_device *pdev)
> > >        * mode->clock and format are not available. So initialize DPHY
> with
> > >        * timing parameters for 80Mbps.
> > >        */
> > > -     ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000);
> > > +     ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000000);
> > >       if (ret < 0)
> > >               goto err_phy;
> > >
> >
> > --
> > Regards,
> >
> > Laurent Pinchart

Re: [PATCH v5 05/12] drm: renesas: rz-du: mipi_dsi: Use VCLK for HSFREQ calculation

[Geert Uytterhoeven]

Hi Prabhakar,

On Mon, 12 May 2025 at 20:23, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Update the RZ/G2L MIPI DSI driver to calculate HSFREQ using the actual
> VCLK rate instead of the mode clock. The relationship between HSCLK and
> VCLK is:
>
>     vclk * bpp <= hsclk * 8 * lanes
>
> Retrieve the VCLK rate using `clk_get_rate(dsi->vclk)`, ensuring that
> HSFREQ accurately reflects the clock rate set in hardware, leading to
> better precision in data transmission.
>
> Additionally, use `DIV_ROUND_CLOSEST_ULL` for a more precise division
> when computing `hsfreq`. Also, update unit conversions to use correct
> scaling factors for better clarity and correctness.
>
> Since `clk_get_rate()` returns the clock rate in Hz, update the HSFREQ
> threshold comparisons to use Hz instead of kHz to ensure correct behavior.
>
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v4->v5:
> - Added dev_info() to print the VCLK rate if it doesn't match the
>   requested rate.
> - Added Reviewed-by tag from Biju
>
> v3->v4:
> - Used MILLI instead of KILO

Thanks for the update!

> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c

> @@ -269,6 +271,12 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>         u32 golpbkt;
>         int ret;
>
> +       ret = pm_runtime_resume_and_get(dsi->dev);
> +       if (ret < 0)
> +               return ret;
> +
> +       clk_set_rate(dsi->vclk, mode->clock * MILLI);

drm_display_mode.clock is in kHz, so s/MILLI/KILO/

> +
>         /*
>          * Relationship between hsclk and vclk must follow
>          * vclk * bpp = hsclk * 8 * lanes
> @@ -280,13 +288,11 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>          * hsclk(bit) = hsclk(byte) * 8 = hsfreq
>          */
>         bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> -       hsfreq = (mode->clock * bpp) / dsi->lanes;
> -
> -       ret = pm_runtime_resume_and_get(dsi->dev);
> -       if (ret < 0)
> -               return ret;
> -
> -       clk_set_rate(dsi->vclk, mode->clock * 1000);
> +       vclk_rate = clk_get_rate(dsi->vclk);
> +       if (vclk_rate != mode->clock * MILLI)
> +               dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
> +                        mode->clock * MILLI, vclk_rate);

Likewise.

> +       hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
>
>         ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
>         if (ret < 0)

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v5 05/12] drm: renesas: rz-du: mipi_dsi: Use VCLK for HSFREQ calculation

[Lad, Prabhakar]

Hi Geert,

Thank you for the review.

On Tue, May 20, 2025 at 3:55 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Prabhakar,
>
> On Mon, 12 May 2025 at 20:23, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Update the RZ/G2L MIPI DSI driver to calculate HSFREQ using the actual
> > VCLK rate instead of the mode clock. The relationship between HSCLK and
> > VCLK is:
> >
> >     vclk * bpp <= hsclk * 8 * lanes
> >
> > Retrieve the VCLK rate using `clk_get_rate(dsi->vclk)`, ensuring that
> > HSFREQ accurately reflects the clock rate set in hardware, leading to
> > better precision in data transmission.
> >
> > Additionally, use `DIV_ROUND_CLOSEST_ULL` for a more precise division
> > when computing `hsfreq`. Also, update unit conversions to use correct
> > scaling factors for better clarity and correctness.
> >
> > Since `clk_get_rate()` returns the clock rate in Hz, update the HSFREQ
> > threshold comparisons to use Hz instead of kHz to ensure correct behavior.
> >
> > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> > v4->v5:
> > - Added dev_info() to print the VCLK rate if it doesn't match the
> >   requested rate.
> > - Added Reviewed-by tag from Biju
> >
> > v3->v4:
> > - Used MILLI instead of KILO
>
> Thanks for the update!
>
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
>
> > @@ -269,6 +271,12 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >         u32 golpbkt;
> >         int ret;
> >
> > +       ret = pm_runtime_resume_and_get(dsi->dev);
> > +       if (ret < 0)
> > +               return ret;
> > +
> > +       clk_set_rate(dsi->vclk, mode->clock * MILLI);
>
> drm_display_mode.clock is in kHz, so s/MILLI/KILO/
>
Agreed, I will update it to use KILO (and below).

Cheers,
Prabhakar

> > +
> >         /*
> >          * Relationship between hsclk and vclk must follow
> >          * vclk * bpp = hsclk * 8 * lanes
> > @@ -280,13 +288,11 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >          * hsclk(bit) = hsclk(byte) * 8 = hsfreq
> >          */
> >         bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> > -       hsfreq = (mode->clock * bpp) / dsi->lanes;
> > -
> > -       ret = pm_runtime_resume_and_get(dsi->dev);
> > -       if (ret < 0)
> > -               return ret;
> > -
> > -       clk_set_rate(dsi->vclk, mode->clock * 1000);
> > +       vclk_rate = clk_get_rate(dsi->vclk);
> > +       if (vclk_rate != mode->clock * MILLI)
> > +               dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
> > +                        mode->clock * MILLI, vclk_rate);
>
> Likewise.
>
> > +       hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
> >
> >         ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
> >         if (ret < 0)
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds

[PATCH v5 06/12] drm: renesas: rz-du: mipi_dsi: Add OF data support

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

In preparation for adding support for the Renesas RZ/V2H(P) SoC, this patch
introduces a mechanism to pass SoC-specific information via OF data in the
DSI driver. This enables the driver to adapt dynamically to various
SoC-specific requirements without hardcoding configurations.

The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to the one
on the RZ/G2L SoC. While the LINK registers are shared between the two
SoCs, the D-PHY registers differ. Also the VCLK range differs on both these
SoCs. To accommodate these differences `struct rzg2l_mipi_dsi_hw_info` is
introduced and as now passed as OF data.

These changes lay the groundwork for the upcoming RZ/V2H(P) SoC support by
allowing SoC-specific data to be passed through OF.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Dropped RZ_MIPI_DSI_FEATURE_DPHY_RST feature flag
- Added Reviewed tag from Biju

v3->v4:
- No changes

v2->v3:
- Dropped !dsi->info check in rzg2l_mipi_dsi_probe() as it is not needed.

v1->v2:
- Added DPHY_RST as feature flag
---
 .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 51 ++++++++++++++-----
 .../drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h   |  2 -
 2 files changed, 38 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index 3f6988303e63..00c2bc6e9d6c 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -28,10 +28,23 @@
 
 #include "rzg2l_mipi_dsi_regs.h"
 
+struct rzg2l_mipi_dsi;
+
+struct rzg2l_mipi_dsi_hw_info {
+	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, unsigned long hsfreq);
+	void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
+	u32 phy_reg_offset;
+	u32 link_reg_offset;
+	unsigned long max_dclk;
+	unsigned long min_dclk;
+};
+
 struct rzg2l_mipi_dsi {
 	struct device *dev;
 	void __iomem *mmio;
 
+	const struct rzg2l_mipi_dsi_hw_info *info;
+
 	struct reset_control *rstc;
 	struct reset_control *arstc;
 	struct reset_control *prstc;
@@ -164,22 +177,22 @@ static const struct rzg2l_mipi_dsi_timings rzg2l_mipi_dsi_global_timings[] = {
 
 static void rzg2l_mipi_dsi_phy_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
 {
-	iowrite32(data, dsi->mmio + reg);
+	iowrite32(data, dsi->mmio + dsi->info->phy_reg_offset + reg);
 }
 
 static void rzg2l_mipi_dsi_link_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
 {
-	iowrite32(data, dsi->mmio + LINK_REG_OFFSET + reg);
+	iowrite32(data, dsi->mmio + dsi->info->link_reg_offset + reg);
 }
 
 static u32 rzg2l_mipi_dsi_phy_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
 {
-	return ioread32(dsi->mmio + reg);
+	return ioread32(dsi->mmio + dsi->info->phy_reg_offset + reg);
 }
 
 static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
 {
-	return ioread32(dsi->mmio + LINK_REG_OFFSET + reg);
+	return ioread32(dsi->mmio + dsi->info->link_reg_offset + reg);
 }
 
 /* -----------------------------------------------------------------------------
@@ -294,7 +307,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 			 mode->clock * MILLI, vclk_rate);
 	hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
 
-	ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
+	ret = dsi->info->dphy_init(dsi, hsfreq);
 	if (ret < 0)
 		goto err_phy;
 
@@ -337,7 +350,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	return 0;
 
 err_phy:
-	rzg2l_mipi_dsi_dphy_exit(dsi);
+	dsi->info->dphy_exit(dsi);
 	pm_runtime_put(dsi->dev);
 
 	return ret;
@@ -345,7 +358,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 
 static void rzg2l_mipi_dsi_stop(struct rzg2l_mipi_dsi *dsi)
 {
-	rzg2l_mipi_dsi_dphy_exit(dsi);
+	dsi->info->dphy_exit(dsi);
 	pm_runtime_put(dsi->dev);
 }
 
@@ -587,10 +600,12 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
 				 const struct drm_display_info *info,
 				 const struct drm_display_mode *mode)
 {
-	if (mode->clock > 148500)
+	struct rzg2l_mipi_dsi *dsi = bridge_to_rzg2l_mipi_dsi(bridge);
+
+	if (mode->clock > dsi->info->max_dclk)
 		return MODE_CLOCK_HIGH;
 
-	if (mode->clock < 5803)
+	if (mode->clock < dsi->info->min_dclk)
 		return MODE_CLOCK_LOW;
 
 	return MODE_OK;
@@ -716,6 +731,8 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, dsi);
 	dsi->dev = &pdev->dev;
 
+	dsi->info = of_device_get_match_data(&pdev->dev);
+
 	ret = drm_of_get_data_lanes_count_ep(dsi->dev->of_node, 1, 0, 1, 4);
 	if (ret < 0)
 		return dev_err_probe(dsi->dev, ret,
@@ -759,13 +776,13 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
 	 * mode->clock and format are not available. So initialize DPHY with
 	 * timing parameters for 80Mbps.
 	 */
-	ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000000);
+	ret = dsi->info->dphy_init(dsi, 80000000);
 	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);
+	dsi->info->dphy_exit(dsi);
 	pm_runtime_put(dsi->dev);
 
 	/* Initialize the DRM bridge. */
@@ -782,7 +799,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
 	return 0;
 
 err_phy:
-	rzg2l_mipi_dsi_dphy_exit(dsi);
+	dsi->info->dphy_exit(dsi);
 	pm_runtime_put(dsi->dev);
 err_pm_disable:
 	pm_runtime_disable(dsi->dev);
@@ -797,8 +814,16 @@ static void rzg2l_mipi_dsi_remove(struct platform_device *pdev)
 	pm_runtime_disable(&pdev->dev);
 }
 
+static const struct rzg2l_mipi_dsi_hw_info rzg2l_mipi_dsi_info = {
+	.dphy_init = rzg2l_mipi_dsi_dphy_init,
+	.dphy_exit = rzg2l_mipi_dsi_dphy_exit,
+	.link_reg_offset = 0x10000,
+	.max_dclk = 148500,
+	.min_dclk = 5803,
+};
+
 static const struct of_device_id rzg2l_mipi_dsi_of_table[] = {
-	{ .compatible = "renesas,rzg2l-mipi-dsi" },
+	{ .compatible = "renesas,rzg2l-mipi-dsi", .data = &rzg2l_mipi_dsi_info, },
 	{ /* sentinel */ }
 };
 
diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
index 1dbc16ec64a4..16efe4dc59f4 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
@@ -41,8 +41,6 @@
 #define DSIDPHYTIM3_THS_ZERO(x)		((x) << 0)
 
 /* --------------------------------------------------------*/
-/* Link Registers */
-#define LINK_REG_OFFSET			0x10000
 
 /* Link Status Register */
 #define LINKSR				0x10
-- 
2.49.0

Re: [PATCH v5 06/12] drm: renesas: rz-du: mipi_dsi: Add OF data support

[Laurent Pinchart]

Hi Prabhakar,

Thank you for the patch.

On Mon, May 12, 2025 at 07:23:24PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> In preparation for adding support for the Renesas RZ/V2H(P) SoC, this patch
> introduces a mechanism to pass SoC-specific information via OF data in the
> DSI driver. This enables the driver to adapt dynamically to various
> SoC-specific requirements without hardcoding configurations.
> 
> The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to the one
> on the RZ/G2L SoC. While the LINK registers are shared between the two
> SoCs, the D-PHY registers differ. Also the VCLK range differs on both these
> SoCs. To accommodate these differences `struct rzg2l_mipi_dsi_hw_info` is
> introduced and as now passed as OF data.
> 
> These changes lay the groundwork for the upcoming RZ/V2H(P) SoC support by
> allowing SoC-specific data to be passed through OF.
> 
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v4->v5:
> - Dropped RZ_MIPI_DSI_FEATURE_DPHY_RST feature flag
> - Added Reviewed tag from Biju
> 
> v3->v4:
> - No changes
> 
> v2->v3:
> - Dropped !dsi->info check in rzg2l_mipi_dsi_probe() as it is not needed.
> 
> v1->v2:
> - Added DPHY_RST as feature flag
> ---
>  .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 51 ++++++++++++++-----
>  .../drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h   |  2 -
>  2 files changed, 38 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index 3f6988303e63..00c2bc6e9d6c 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -28,10 +28,23 @@
>  
>  #include "rzg2l_mipi_dsi_regs.h"
>  
> +struct rzg2l_mipi_dsi;
> +
> +struct rzg2l_mipi_dsi_hw_info {
> +	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, unsigned long hsfreq);
> +	void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
> +	u32 phy_reg_offset;
> +	u32 link_reg_offset;
> +	unsigned long max_dclk;
> +	unsigned long min_dclk;

I'd put min before max.

> +};
> +
>  struct rzg2l_mipi_dsi {
>  	struct device *dev;
>  	void __iomem *mmio;
>  
> +	const struct rzg2l_mipi_dsi_hw_info *info;
> +
>  	struct reset_control *rstc;
>  	struct reset_control *arstc;
>  	struct reset_control *prstc;
> @@ -164,22 +177,22 @@ static const struct rzg2l_mipi_dsi_timings rzg2l_mipi_dsi_global_timings[] = {
>  
>  static void rzg2l_mipi_dsi_phy_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
>  {
> -	iowrite32(data, dsi->mmio + reg);
> +	iowrite32(data, dsi->mmio + dsi->info->phy_reg_offset + reg);
>  }
>  
>  static void rzg2l_mipi_dsi_link_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
>  {
> -	iowrite32(data, dsi->mmio + LINK_REG_OFFSET + reg);
> +	iowrite32(data, dsi->mmio + dsi->info->link_reg_offset + reg);
>  }
>  
>  static u32 rzg2l_mipi_dsi_phy_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
>  {
> -	return ioread32(dsi->mmio + reg);
> +	return ioread32(dsi->mmio + dsi->info->phy_reg_offset + reg);
>  }
>  
>  static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
>  {
> -	return ioread32(dsi->mmio + LINK_REG_OFFSET + reg);
> +	return ioread32(dsi->mmio + dsi->info->link_reg_offset + reg);
>  }
>  
>  /* -----------------------------------------------------------------------------
> @@ -294,7 +307,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  			 mode->clock * MILLI, vclk_rate);
>  	hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
>  
> -	ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
> +	ret = dsi->info->dphy_init(dsi, hsfreq);
>  	if (ret < 0)
>  		goto err_phy;
>  
> @@ -337,7 +350,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  	return 0;
>  
>  err_phy:
> -	rzg2l_mipi_dsi_dphy_exit(dsi);
> +	dsi->info->dphy_exit(dsi);
>  	pm_runtime_put(dsi->dev);
>  
>  	return ret;
> @@ -345,7 +358,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  
>  static void rzg2l_mipi_dsi_stop(struct rzg2l_mipi_dsi *dsi)
>  {
> -	rzg2l_mipi_dsi_dphy_exit(dsi);
> +	dsi->info->dphy_exit(dsi);
>  	pm_runtime_put(dsi->dev);
>  }
>  
> @@ -587,10 +600,12 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
>  				 const struct drm_display_info *info,
>  				 const struct drm_display_mode *mode)
>  {
> -	if (mode->clock > 148500)
> +	struct rzg2l_mipi_dsi *dsi = bridge_to_rzg2l_mipi_dsi(bridge);
> +
> +	if (mode->clock > dsi->info->max_dclk)
>  		return MODE_CLOCK_HIGH;
>  
> -	if (mode->clock < 5803)
> +	if (mode->clock < dsi->info->min_dclk)
>  		return MODE_CLOCK_LOW;
>  
>  	return MODE_OK;
> @@ -716,6 +731,8 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>  	platform_set_drvdata(pdev, dsi);
>  	dsi->dev = &pdev->dev;
>  
> +	dsi->info = of_device_get_match_data(&pdev->dev);
> +
>  	ret = drm_of_get_data_lanes_count_ep(dsi->dev->of_node, 1, 0, 1, 4);
>  	if (ret < 0)
>  		return dev_err_probe(dsi->dev, ret,
> @@ -759,13 +776,13 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>  	 * mode->clock and format are not available. So initialize DPHY with
>  	 * timing parameters for 80Mbps.
>  	 */
> -	ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000000);
> +	ret = dsi->info->dphy_init(dsi, 80000000);
>  	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);
> +	dsi->info->dphy_exit(dsi);
>  	pm_runtime_put(dsi->dev);
>  
>  	/* Initialize the DRM bridge. */
> @@ -782,7 +799,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>  	return 0;
>  
>  err_phy:
> -	rzg2l_mipi_dsi_dphy_exit(dsi);
> +	dsi->info->dphy_exit(dsi);
>  	pm_runtime_put(dsi->dev);
>  err_pm_disable:
>  	pm_runtime_disable(dsi->dev);
> @@ -797,8 +814,16 @@ static void rzg2l_mipi_dsi_remove(struct platform_device *pdev)
>  	pm_runtime_disable(&pdev->dev);
>  }
>  
> +static const struct rzg2l_mipi_dsi_hw_info rzg2l_mipi_dsi_info = {
> +	.dphy_init = rzg2l_mipi_dsi_dphy_init,
> +	.dphy_exit = rzg2l_mipi_dsi_dphy_exit,
> +	.link_reg_offset = 0x10000,
> +	.max_dclk = 148500,
> +	.min_dclk = 5803,

Here too.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> +};
> +
>  static const struct of_device_id rzg2l_mipi_dsi_of_table[] = {
> -	{ .compatible = "renesas,rzg2l-mipi-dsi" },
> +	{ .compatible = "renesas,rzg2l-mipi-dsi", .data = &rzg2l_mipi_dsi_info, },
>  	{ /* sentinel */ }
>  };
>  
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> index 1dbc16ec64a4..16efe4dc59f4 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> @@ -41,8 +41,6 @@
>  #define DSIDPHYTIM3_THS_ZERO(x)		((x) << 0)
>  
>  /* --------------------------------------------------------*/
> -/* Link Registers */
> -#define LINK_REG_OFFSET			0x10000
>  
>  /* Link Status Register */
>  #define LINKSR				0x10

-- 
Regards,

Laurent Pinchart

Re: [PATCH v5 06/12] drm: renesas: rz-du: mipi_dsi: Add OF data support

[Lad, Prabhakar]

Hi Laurent,

Thank you for the review.

On Tue, May 20, 2025 at 3:22 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hi Prabhakar,
>
> Thank you for the patch.
>
> On Mon, May 12, 2025 at 07:23:24PM +0100, Prabhakar wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > In preparation for adding support for the Renesas RZ/V2H(P) SoC, this patch
> > introduces a mechanism to pass SoC-specific information via OF data in the
> > DSI driver. This enables the driver to adapt dynamically to various
> > SoC-specific requirements without hardcoding configurations.
> >
> > The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to the one
> > on the RZ/G2L SoC. While the LINK registers are shared between the two
> > SoCs, the D-PHY registers differ. Also the VCLK range differs on both these
> > SoCs. To accommodate these differences `struct rzg2l_mipi_dsi_hw_info` is
> > introduced and as now passed as OF data.
> >
> > These changes lay the groundwork for the upcoming RZ/V2H(P) SoC support by
> > allowing SoC-specific data to be passed through OF.
> >
> > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> > v4->v5:
> > - Dropped RZ_MIPI_DSI_FEATURE_DPHY_RST feature flag
> > - Added Reviewed tag from Biju
> >
> > v3->v4:
> > - No changes
> >
> > v2->v3:
> > - Dropped !dsi->info check in rzg2l_mipi_dsi_probe() as it is not needed.
> >
> > v1->v2:
> > - Added DPHY_RST as feature flag
> > ---
> >  .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 51 ++++++++++++++-----
> >  .../drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h   |  2 -
> >  2 files changed, 38 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > index 3f6988303e63..00c2bc6e9d6c 100644
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > @@ -28,10 +28,23 @@
> >
> >  #include "rzg2l_mipi_dsi_regs.h"
> >
> > +struct rzg2l_mipi_dsi;
> > +
> > +struct rzg2l_mipi_dsi_hw_info {
> > +     int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, unsigned long hsfreq);
> > +     void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
> > +     u32 phy_reg_offset;
> > +     u32 link_reg_offset;
> > +     unsigned long max_dclk;
> > +     unsigned long min_dclk;
>
> I'd put min before max.
>
Sure, I'll swap them (and below).

Cheers,
Prabhakar

> > +};
> > +
> >  struct rzg2l_mipi_dsi {
> >       struct device *dev;
> >       void __iomem *mmio;
> >
> > +     const struct rzg2l_mipi_dsi_hw_info *info;
> > +
> >       struct reset_control *rstc;
> >       struct reset_control *arstc;
> >       struct reset_control *prstc;
> > @@ -164,22 +177,22 @@ static const struct rzg2l_mipi_dsi_timings rzg2l_mipi_dsi_global_timings[] = {
> >
> >  static void rzg2l_mipi_dsi_phy_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
> >  {
> > -     iowrite32(data, dsi->mmio + reg);
> > +     iowrite32(data, dsi->mmio + dsi->info->phy_reg_offset + reg);
> >  }
> >
> >  static void rzg2l_mipi_dsi_link_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
> >  {
> > -     iowrite32(data, dsi->mmio + LINK_REG_OFFSET + reg);
> > +     iowrite32(data, dsi->mmio + dsi->info->link_reg_offset + reg);
> >  }
> >
> >  static u32 rzg2l_mipi_dsi_phy_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
> >  {
> > -     return ioread32(dsi->mmio + reg);
> > +     return ioread32(dsi->mmio + dsi->info->phy_reg_offset + reg);
> >  }
> >
> >  static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
> >  {
> > -     return ioread32(dsi->mmio + LINK_REG_OFFSET + reg);
> > +     return ioread32(dsi->mmio + dsi->info->link_reg_offset + reg);
> >  }
> >
> >  /* -----------------------------------------------------------------------------
> > @@ -294,7 +307,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >                        mode->clock * MILLI, vclk_rate);
> >       hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
> >
> > -     ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
> > +     ret = dsi->info->dphy_init(dsi, hsfreq);
> >       if (ret < 0)
> >               goto err_phy;
> >
> > @@ -337,7 +350,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >       return 0;
> >
> >  err_phy:
> > -     rzg2l_mipi_dsi_dphy_exit(dsi);
> > +     dsi->info->dphy_exit(dsi);
> >       pm_runtime_put(dsi->dev);
> >
> >       return ret;
> > @@ -345,7 +358,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >
> >  static void rzg2l_mipi_dsi_stop(struct rzg2l_mipi_dsi *dsi)
> >  {
> > -     rzg2l_mipi_dsi_dphy_exit(dsi);
> > +     dsi->info->dphy_exit(dsi);
> >       pm_runtime_put(dsi->dev);
> >  }
> >
> > @@ -587,10 +600,12 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
> >                                const struct drm_display_info *info,
> >                                const struct drm_display_mode *mode)
> >  {
> > -     if (mode->clock > 148500)
> > +     struct rzg2l_mipi_dsi *dsi = bridge_to_rzg2l_mipi_dsi(bridge);
> > +
> > +     if (mode->clock > dsi->info->max_dclk)
> >               return MODE_CLOCK_HIGH;
> >
> > -     if (mode->clock < 5803)
> > +     if (mode->clock < dsi->info->min_dclk)
> >               return MODE_CLOCK_LOW;
> >
> >       return MODE_OK;
> > @@ -716,6 +731,8 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
> >       platform_set_drvdata(pdev, dsi);
> >       dsi->dev = &pdev->dev;
> >
> > +     dsi->info = of_device_get_match_data(&pdev->dev);
> > +
> >       ret = drm_of_get_data_lanes_count_ep(dsi->dev->of_node, 1, 0, 1, 4);
> >       if (ret < 0)
> >               return dev_err_probe(dsi->dev, ret,
> > @@ -759,13 +776,13 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
> >        * mode->clock and format are not available. So initialize DPHY with
> >        * timing parameters for 80Mbps.
> >        */
> > -     ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000000);
> > +     ret = dsi->info->dphy_init(dsi, 80000000);
> >       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);
> > +     dsi->info->dphy_exit(dsi);
> >       pm_runtime_put(dsi->dev);
> >
> >       /* Initialize the DRM bridge. */
> > @@ -782,7 +799,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
> >       return 0;
> >
> >  err_phy:
> > -     rzg2l_mipi_dsi_dphy_exit(dsi);
> > +     dsi->info->dphy_exit(dsi);
> >       pm_runtime_put(dsi->dev);
> >  err_pm_disable:
> >       pm_runtime_disable(dsi->dev);
> > @@ -797,8 +814,16 @@ static void rzg2l_mipi_dsi_remove(struct platform_device *pdev)
> >       pm_runtime_disable(&pdev->dev);
> >  }
> >
> > +static const struct rzg2l_mipi_dsi_hw_info rzg2l_mipi_dsi_info = {
> > +     .dphy_init = rzg2l_mipi_dsi_dphy_init,
> > +     .dphy_exit = rzg2l_mipi_dsi_dphy_exit,
> > +     .link_reg_offset = 0x10000,
> > +     .max_dclk = 148500,
> > +     .min_dclk = 5803,
>
> Here too.
>
> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
>
> > +};
> > +
> >  static const struct of_device_id rzg2l_mipi_dsi_of_table[] = {
> > -     { .compatible = "renesas,rzg2l-mipi-dsi" },
> > +     { .compatible = "renesas,rzg2l-mipi-dsi", .data = &rzg2l_mipi_dsi_info, },
> >       { /* sentinel */ }
> >  };
> >
> > diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> > index 1dbc16ec64a4..16efe4dc59f4 100644
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
> > @@ -41,8 +41,6 @@
> >  #define DSIDPHYTIM3_THS_ZERO(x)              ((x) << 0)
> >
> >  /* --------------------------------------------------------*/
> > -/* Link Registers */
> > -#define LINK_REG_OFFSET                      0x10000
> >
> >  /* Link Status Register */
> >  #define LINKSR                               0x10
>
> --
> Regards,
>
> Laurent Pinchart

[PATCH v5 07/12] drm: renesas: rz-du: mipi_dsi: Make "rst" reset control optional for RZ/V2H(P)

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

In preparation for adding support for the Renesas RZ/V2H(P) SoC, make the
"rst" reset control optional in the MIPI DSI driver. The RZ/V2H(P) SoC
does not provide this reset line, and attempting to acquire it using the
mandatory API causes probe failure.

Switching to devm_reset_control_get_optional_exclusive() ensures
compatibility with both SoCs that provide this reset line and those that
do not, such as RZ/V2H(P).

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
v4->v5:
- New patch
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index 00c2bc6e9d6c..5fc607be0c46 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -748,7 +748,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
 	if (IS_ERR(dsi->vclk))
 		return PTR_ERR(dsi->vclk);
 
-	dsi->rstc = devm_reset_control_get_exclusive(dsi->dev, "rst");
+	dsi->rstc = devm_reset_control_get_optional_exclusive(dsi->dev, "rst");
 	if (IS_ERR(dsi->rstc))
 		return dev_err_probe(dsi->dev, PTR_ERR(dsi->rstc),
 				     "failed to get rst\n");
-- 
2.49.0

RE: [PATCH v5 07/12] drm: renesas: rz-du: mipi_dsi: Make "rst" reset control optional for RZ/V2H(P)

[Biju Das]

Hi Prabhakar,

Thanks for the patch.

> -----Original Message-----
> From: Prabhakar <prabhakar.csengg@gmail.com>
> Sent: 12 May 2025 19:23
> Subject: [PATCH v5 07/12] drm: renesas: rz-du: mipi_dsi: Make "rst" reset control optional for
> RZ/V2H(P)
> 
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> In preparation for adding support for the Renesas RZ/V2H(P) SoC, make the "rst" reset control optional
> in the MIPI DSI driver. The RZ/V2H(P) SoC does not provide this reset line, and attempting to acquire
> it using the mandatory API causes probe failure.
> 
> Switching to devm_reset_control_get_optional_exclusive() ensures compatibility with both SoCs that
> provide this reset line and those that do not, such as RZ/V2H(P).
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>

Cheers,
Biju

> ---
> v4->v5:
> - New patch
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-
> du/rzg2l_mipi_dsi.c
> index 00c2bc6e9d6c..5fc607be0c46 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -748,7 +748,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>  	if (IS_ERR(dsi->vclk))
>  		return PTR_ERR(dsi->vclk);
> 
> -	dsi->rstc = devm_reset_control_get_exclusive(dsi->dev, "rst");
> +	dsi->rstc = devm_reset_control_get_optional_exclusive(dsi->dev,
> +"rst");
>  	if (IS_ERR(dsi->rstc))
>  		return dev_err_probe(dsi->dev, PTR_ERR(dsi->rstc),
>  				     "failed to get rst\n");
> --
> 2.49.0

Re: [PATCH v5 07/12] drm: renesas: rz-du: mipi_dsi: Make "rst" reset control optional for RZ/V2H(P)

[Laurent Pinchart]

Hi Prabhakar,

On Mon, May 12, 2025 at 07:23:25PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> In preparation for adding support for the Renesas RZ/V2H(P) SoC, make the
> "rst" reset control optional in the MIPI DSI driver. The RZ/V2H(P) SoC
> does not provide this reset line, and attempting to acquire it using the
> mandatory API causes probe failure.
> 
> Switching to devm_reset_control_get_optional_exclusive() ensures
> compatibility with both SoCs that provide this reset line and those that
> do not, such as RZ/V2H(P).
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> ---
> v4->v5:
> - New patch
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index 00c2bc6e9d6c..5fc607be0c46 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -748,7 +748,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>  	if (IS_ERR(dsi->vclk))
>  		return PTR_ERR(dsi->vclk);
>  
> -	dsi->rstc = devm_reset_control_get_exclusive(dsi->dev, "rst");
> +	dsi->rstc = devm_reset_control_get_optional_exclusive(dsi->dev, "rst");
>  	if (IS_ERR(dsi->rstc))
>  		return dev_err_probe(dsi->dev, PTR_ERR(dsi->rstc),
>  				     "failed to get rst\n");

-- 
Regards,

Laurent Pinchart

[PATCH v5 08/12] drm: renesas: rz-du: mipi_dsi: Use mHz for D-PHY frequency calculations

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Pass the HSFREQ in milli-Hz to the `dphy_init()` callback to improve
precision, especially for the RZ/V2H(P) SoC, where PLL dividers require
high accuracy.

These changes prepare the driver for upcoming RZ/V2H(P) SoC support.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Added Reviewed tag from Biju

v3->v4:
- Used MILLI instead of KILO
- Made use of mul_u32_u32() for multiplication

v2->v3:
- Replaced `unsigned long long` with `u64`
- Replaced *_mhz with *_millihz` in functions

v1->v2:
- No changes
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index 5fc607be0c46..f93519613662 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -31,7 +31,7 @@
 struct rzg2l_mipi_dsi;
 
 struct rzg2l_mipi_dsi_hw_info {
-	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, unsigned long hsfreq);
+	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, u64 hsfreq_millihz);
 	void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
 	u32 phy_reg_offset;
 	u32 link_reg_offset;
@@ -200,8 +200,9 @@ static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
  */
 
 static int rzg2l_mipi_dsi_dphy_init(struct rzg2l_mipi_dsi *dsi,
-				    unsigned long hsfreq)
+				    u64 hsfreq_millihz)
 {
+	unsigned long hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
 	const struct rzg2l_mipi_dsi_timings *dphy_timings;
 	unsigned int i;
 	u32 dphyctrl0;
@@ -274,6 +275,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 				  const struct drm_display_mode *mode)
 {
 	unsigned long hsfreq, vclk_rate;
+	u64 hsfreq_millihz;
 	unsigned int bpp;
 	u32 txsetr;
 	u32 clstptsetr;
@@ -305,9 +307,9 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	if (vclk_rate != mode->clock * MILLI)
 		dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
 			 mode->clock * MILLI, vclk_rate);
-	hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
+	hsfreq_millihz = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(vclk_rate, bpp * MILLI), dsi->lanes);
 
-	ret = dsi->info->dphy_init(dsi, hsfreq);
+	ret = dsi->info->dphy_init(dsi, hsfreq_millihz);
 	if (ret < 0)
 		goto err_phy;
 
@@ -315,6 +317,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	txsetr = TXSETR_DLEN | TXSETR_NUMLANEUSE(dsi->lanes - 1) | TXSETR_CLEN;
 	rzg2l_mipi_dsi_link_write(dsi, TXSETR, txsetr);
 
+	hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
 	/*
 	 * Global timings characteristic depends on high speed Clock Frequency
 	 * Currently MIPI DSI-IF just supports maximum FHD@60 with:
@@ -776,7 +779,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
 	 * mode->clock and format are not available. So initialize DPHY with
 	 * timing parameters for 80Mbps.
 	 */
-	ret = dsi->info->dphy_init(dsi, 80000000);
+	ret = dsi->info->dphy_init(dsi, 80000000ULL * MILLI);
 	if (ret < 0)
 		goto err_phy;
 
-- 
2.49.0

Re: [PATCH v5 08/12] drm: renesas: rz-du: mipi_dsi: Use mHz for D-PHY frequency calculations

[Laurent Pinchart]

Hi Prabhakar,

Thank you for the patch.

On Mon, May 12, 2025 at 07:23:26PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> Pass the HSFREQ in milli-Hz to the `dphy_init()` callback to improve
> precision, especially for the RZ/V2H(P) SoC, where PLL dividers require
> high accuracy.

I have a hard time imagining the need for milliHz accuracy. Could you
please explain why that is needed on V2H ?

> These changes prepare the driver for upcoming RZ/V2H(P) SoC support.
> 
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v4->v5:
> - Added Reviewed tag from Biju
> 
> v3->v4:
> - Used MILLI instead of KILO
> - Made use of mul_u32_u32() for multiplication
> 
> v2->v3:
> - Replaced `unsigned long long` with `u64`
> - Replaced *_mhz with *_millihz` in functions
> 
> v1->v2:
> - No changes
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index 5fc607be0c46..f93519613662 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -31,7 +31,7 @@
>  struct rzg2l_mipi_dsi;
>  
>  struct rzg2l_mipi_dsi_hw_info {
> -	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, unsigned long hsfreq);
> +	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, u64 hsfreq_millihz);
>  	void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
>  	u32 phy_reg_offset;
>  	u32 link_reg_offset;
> @@ -200,8 +200,9 @@ static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
>   */
>  
>  static int rzg2l_mipi_dsi_dphy_init(struct rzg2l_mipi_dsi *dsi,
> -				    unsigned long hsfreq)
> +				    u64 hsfreq_millihz)
>  {
> +	unsigned long hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
>  	const struct rzg2l_mipi_dsi_timings *dphy_timings;
>  	unsigned int i;
>  	u32 dphyctrl0;
> @@ -274,6 +275,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  				  const struct drm_display_mode *mode)
>  {
>  	unsigned long hsfreq, vclk_rate;
> +	u64 hsfreq_millihz;
>  	unsigned int bpp;
>  	u32 txsetr;
>  	u32 clstptsetr;
> @@ -305,9 +307,9 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  	if (vclk_rate != mode->clock * MILLI)
>  		dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
>  			 mode->clock * MILLI, vclk_rate);
> -	hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
> +	hsfreq_millihz = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(vclk_rate, bpp * MILLI), dsi->lanes);
>  
> -	ret = dsi->info->dphy_init(dsi, hsfreq);
> +	ret = dsi->info->dphy_init(dsi, hsfreq_millihz);
>  	if (ret < 0)
>  		goto err_phy;
>  
> @@ -315,6 +317,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  	txsetr = TXSETR_DLEN | TXSETR_NUMLANEUSE(dsi->lanes - 1) | TXSETR_CLEN;
>  	rzg2l_mipi_dsi_link_write(dsi, TXSETR, txsetr);
>  
> +	hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
>  	/*
>  	 * Global timings characteristic depends on high speed Clock Frequency
>  	 * Currently MIPI DSI-IF just supports maximum FHD@60 with:
> @@ -776,7 +779,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
>  	 * mode->clock and format are not available. So initialize DPHY with
>  	 * timing parameters for 80Mbps.
>  	 */
> -	ret = dsi->info->dphy_init(dsi, 80000000);
> +	ret = dsi->info->dphy_init(dsi, 80000000ULL * MILLI);
>  	if (ret < 0)
>  		goto err_phy;
>  

-- 
Regards,

Laurent Pinchart

RE: [PATCH v5 08/12] drm: renesas: rz-du: mipi_dsi: Use mHz for D-PHY frequency calculations

[Fabrizio Castro]

Hi Laurent,

Thanks for your feedback.

> From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Sent: 20 May 2025 15:24
> Subject: Re: [PATCH v5 08/12] drm: renesas: rz-du: mipi_dsi: Use mHz for D-PHY frequency calculations
> 
> Hi Prabhakar,
> 
> Thank you for the patch.
> 
> On Mon, May 12, 2025 at 07:23:26PM +0100, Prabhakar wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Pass the HSFREQ in milli-Hz to the `dphy_init()` callback to improve
> > precision, especially for the RZ/V2H(P) SoC, where PLL dividers require
> > high accuracy.
> 
> I have a hard time imagining the need for milliHz accuracy. Could you
> please explain why that is needed on V2H ?

This is needed because of the clock architecture found on the Renesas RZ/V2H,
in combination with a tight tolerance on the HFSFREQ calculation.

The clock architecture found on the RZ/V2H DSI is modelled as below:

 ______________________________________     ________________________
|                                      |   |                        |
| CPG                                  |   | DSI                    |
|  ________      ____________________  |   |    _____        _____  |
| |        |    |                    | |   |   |     | vclk |     | |
| | PLLDSI |--->| CSDIV_2to32_PLLDSI |-|-->|-->| PLL |----->| PHY | |
| |________|    |____________________| |   |   |_____|      |_____| |
|______________________________________|   |________________________|


The PLL found inside the DSI IP is very similar to the PLLDSI found in the
CPG IP block, although the limits for some of the parameters are different.
Also, the PLLDSI is followed by a programmable divider, whereas there is no
such thing in the DSI PLL IP.

The limits for the PLL found within the DSI IP are:
1 <= PLL_P <= 4
64 <= PLL_M <= 1023
0 <= PLL_S <= 5
−32768 <= PLL_K <= 32767

The limits for PLLDSI (found in CPG) are:
1 <= PLL_P <= 4
64 <= PLL_M <= 533
0 <= PLL_S <= 6
−32768 <= PLL_K <= 32767
The limits for the CSDIV_2to32_PLLDSI divider are:
CSDIV = 1/(2 + 2 * n), with n=0,...,15

Using mHz internally for representing VCLK and HSFREQ is vital to allow the DSI
Driver to keep the error between the calculated value of HSFREQ and the actual
value of HSFREQ below a certain threshold (0.5 Hz).
The difficulty in achieving a small error is down to the accuracy of the VCLK
representation.
Since the clock subsystem only allows for Hz, a 0.5 Hz error on the representation of
VCLK (down to the selection of frequencies that cannot be precisely achieved and
related rounding errors) may lead to a very big error in the calculation
of HSFREQ, which uses the below formula:
HSFREQ = (VCLK * bpp) / num_lanes
In the worst-case scenario (1 lane and 24 bpp), a 0.5 Hz error on the representation
of VCLK will lead to an error of 12 Hz(!) on the calculation of HSFREQ, leading
to a non-working video output.

By internally representing VCLK (and HSFREQ) in mHZ, the maximum error we make on
its representation is 0.5 mHz, with a total maximum error of 12 mHz on the
calculation of HSFREQ.

HSFREQ then gets converted back to Hz (bringing the error back to a maximum value
of 0.5 Hz) for calculating the PHY parameters, which at that point is good enough.

We have empirically proven this, so there is no way around it.

The thing that we got lucky about is that we can use the same algorithm to calculate
the parameters for PLLDSI and for the DSI PLL, therefore by sharing a function between
the CPG driver and the DSI driver we can, to some extent, bypass the limitations
of the clock subsystem and achieve the accuracy required by DSI.

Also, RZ/G3E has a similar architecture therefore it is subjected to similar
constraints.

I hope this clarifies things?

Cheers,
Fab

> 
> > These changes prepare the driver for upcoming RZ/V2H(P) SoC support.
> >
> > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> > v4->v5:
> > - Added Reviewed tag from Biju
> >
> > v3->v4:
> > - Used MILLI instead of KILO
> > - Made use of mul_u32_u32() for multiplication
> >
> > v2->v3:
> > - Replaced `unsigned long long` with `u64`
> > - Replaced *_mhz with *_millihz` in functions
> >
> > v1->v2:
> > - No changes
> > ---
> >  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 13 ++++++++-----
> >  1 file changed, 8 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-
> du/rzg2l_mipi_dsi.c
> > index 5fc607be0c46..f93519613662 100644
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > @@ -31,7 +31,7 @@
> >  struct rzg2l_mipi_dsi;
> >
> >  struct rzg2l_mipi_dsi_hw_info {
> > -	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, unsigned long hsfreq);
> > +	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, u64 hsfreq_millihz);
> >  	void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
> >  	u32 phy_reg_offset;
> >  	u32 link_reg_offset;
> > @@ -200,8 +200,9 @@ static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
> >   */
> >
> >  static int rzg2l_mipi_dsi_dphy_init(struct rzg2l_mipi_dsi *dsi,
> > -				    unsigned long hsfreq)
> > +				    u64 hsfreq_millihz)
> >  {
> > +	unsigned long hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
> >  	const struct rzg2l_mipi_dsi_timings *dphy_timings;
> >  	unsigned int i;
> >  	u32 dphyctrl0;
> > @@ -274,6 +275,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >  				  const struct drm_display_mode *mode)
> >  {
> >  	unsigned long hsfreq, vclk_rate;
> > +	u64 hsfreq_millihz;
> >  	unsigned int bpp;
> >  	u32 txsetr;
> >  	u32 clstptsetr;
> > @@ -305,9 +307,9 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >  	if (vclk_rate != mode->clock * MILLI)
> >  		dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
> >  			 mode->clock * MILLI, vclk_rate);
> > -	hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);
> > +	hsfreq_millihz = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(vclk_rate, bpp * MILLI), dsi->lanes);
> >
> > -	ret = dsi->info->dphy_init(dsi, hsfreq);
> > +	ret = dsi->info->dphy_init(dsi, hsfreq_millihz);
> >  	if (ret < 0)
> >  		goto err_phy;
> >
> > @@ -315,6 +317,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >  	txsetr = TXSETR_DLEN | TXSETR_NUMLANEUSE(dsi->lanes - 1) | TXSETR_CLEN;
> >  	rzg2l_mipi_dsi_link_write(dsi, TXSETR, txsetr);
> >
> > +	hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
> >  	/*
> >  	 * Global timings characteristic depends on high speed Clock Frequency
> >  	 * Currently MIPI DSI-IF just supports maximum FHD@60 with:
> > @@ -776,7 +779,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
> >  	 * mode->clock and format are not available. So initialize DPHY with
> >  	 * timing parameters for 80Mbps.
> >  	 */
> > -	ret = dsi->info->dphy_init(dsi, 80000000);
> > +	ret = dsi->info->dphy_init(dsi, 80000000ULL * MILLI);
> >  	if (ret < 0)
> >  		goto err_phy;
> >
> 
> --
> Regards,
> 
> Laurent Pinchart

[PATCH v5 09/12] drm: renesas: rz-du: mipi_dsi: Add feature flag for 16BPP support

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Introduce the `RZ_MIPI_DSI_FEATURE_16BPP` flag in `rzg2l_mipi_dsi_hw_info`
to indicate support for 16BPP pixel formats. The RZ/V2H(P) SoC supports
16BPP, whereas this feature is missing on the RZ/G2L SoC.

Update the `mipi_dsi_host_attach()` function to check this flag before
allowing 16BPP formats. If the SoC does not support 16BPP, return an error
to prevent incorrect format selection.

This change enables finer-grained format support control for different
SoC variants.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Updated RZ_MIPI_DSI_FEATURE_16BPP macro to use BIT(0)
- Added Reviewed tag from Biju

v3->v4:
- No changes

v2->v3:
- No changes

v1->v2:
- Renamed RZ_MIPI_DSI_FEATURE_16BPP
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index f93519613662..55a1c1b043c8 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -28,6 +28,8 @@
 
 #include "rzg2l_mipi_dsi_regs.h"
 
+#define RZ_MIPI_DSI_FEATURE_16BPP	BIT(0)
+
 struct rzg2l_mipi_dsi;
 
 struct rzg2l_mipi_dsi_hw_info {
@@ -37,6 +39,7 @@ struct rzg2l_mipi_dsi_hw_info {
 	u32 link_reg_offset;
 	unsigned long max_dclk;
 	unsigned long min_dclk;
+	u8 features;
 };
 
 struct rzg2l_mipi_dsi {
@@ -643,8 +646,16 @@ static int rzg2l_mipi_dsi_host_attach(struct mipi_dsi_host *host,
 
 	switch (mipi_dsi_pixel_format_to_bpp(device->format)) {
 	case 24:
+		break;
 	case 18:
 		break;
+	case 16:
+		if (!(dsi->info->features & RZ_MIPI_DSI_FEATURE_16BPP)) {
+			dev_err(dsi->dev, "Unsupported format 0x%04x\n",
+				device->format);
+			return -EINVAL;
+		}
+		break;
 	default:
 		dev_err(dsi->dev, "Unsupported format 0x%04x\n", device->format);
 		return -EINVAL;
-- 
2.49.0

Re: [PATCH v5 09/12] drm: renesas: rz-du: mipi_dsi: Add feature flag for 16BPP support

[Laurent Pinchart]

Hi Prabhakar,

Thank you for the patch.

On Mon, May 12, 2025 at 07:23:27PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> Introduce the `RZ_MIPI_DSI_FEATURE_16BPP` flag in `rzg2l_mipi_dsi_hw_info`
> to indicate support for 16BPP pixel formats. The RZ/V2H(P) SoC supports
> 16BPP, whereas this feature is missing on the RZ/G2L SoC.
> 
> Update the `mipi_dsi_host_attach()` function to check this flag before
> allowing 16BPP formats. If the SoC does not support 16BPP, return an error
> to prevent incorrect format selection.
> 
> This change enables finer-grained format support control for different
> SoC variants.
> 
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> ---
> v4->v5:
> - Updated RZ_MIPI_DSI_FEATURE_16BPP macro to use BIT(0)
> - Added Reviewed tag from Biju
> 
> v3->v4:
> - No changes
> 
> v2->v3:
> - No changes
> 
> v1->v2:
> - Renamed RZ_MIPI_DSI_FEATURE_16BPP
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index f93519613662..55a1c1b043c8 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -28,6 +28,8 @@
>  
>  #include "rzg2l_mipi_dsi_regs.h"
>  
> +#define RZ_MIPI_DSI_FEATURE_16BPP	BIT(0)
> +
>  struct rzg2l_mipi_dsi;
>  
>  struct rzg2l_mipi_dsi_hw_info {
> @@ -37,6 +39,7 @@ struct rzg2l_mipi_dsi_hw_info {
>  	u32 link_reg_offset;
>  	unsigned long max_dclk;
>  	unsigned long min_dclk;
> +	u8 features;
>  };
>  
>  struct rzg2l_mipi_dsi {
> @@ -643,8 +646,16 @@ static int rzg2l_mipi_dsi_host_attach(struct mipi_dsi_host *host,
>  
>  	switch (mipi_dsi_pixel_format_to_bpp(device->format)) {
>  	case 24:
> +		break;
>  	case 18:
>  		break;
> +	case 16:
> +		if (!(dsi->info->features & RZ_MIPI_DSI_FEATURE_16BPP)) {
> +			dev_err(dsi->dev, "Unsupported format 0x%04x\n",
> +				device->format);
> +			return -EINVAL;
> +		}
> +		break;
>  	default:
>  		dev_err(dsi->dev, "Unsupported format 0x%04x\n", device->format);
>  		return -EINVAL;

-- 
Regards,

Laurent Pinchart

[PATCH v5 10/12] drm: renesas: rz-du: mipi_dsi: Add dphy_late_init() callback for RZ/V2H(P)

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Introduce the `dphy_late_init` callback in `rzg2l_mipi_dsi_hw_info` to
allow additional D-PHY register configurations after enabling data and
clock lanes. This is required for the RZ/V2H(P) SoC but not for the
RZ/G2L SoC.

Modify `rzg2l_mipi_dsi_startup()` to invoke `dphy_late_init` if defined,
ensuring SoC-specific initialization is performed only when necessary.

This change prepares for RZ/V2H(P) SoC support while maintaining
compatibility with existing platforms.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Added Reviewed tag from Biju

v3->v4:
- No changes

v2->v3:
- No changes

v1->v2:
- No changes
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index 55a1c1b043c8..e1ce21a9ddb3 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -34,6 +34,7 @@ struct rzg2l_mipi_dsi;
 
 struct rzg2l_mipi_dsi_hw_info {
 	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, u64 hsfreq_millihz);
+	void (*dphy_late_init)(struct rzg2l_mipi_dsi *dsi);
 	void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
 	u32 phy_reg_offset;
 	u32 link_reg_offset;
@@ -320,6 +321,9 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	txsetr = TXSETR_DLEN | TXSETR_NUMLANEUSE(dsi->lanes - 1) | TXSETR_CLEN;
 	rzg2l_mipi_dsi_link_write(dsi, TXSETR, txsetr);
 
+	if (dsi->info->dphy_late_init)
+		dsi->info->dphy_late_init(dsi);
+
 	hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
 	/*
 	 * Global timings characteristic depends on high speed Clock Frequency
-- 
2.49.0

Re: [PATCH v5 10/12] drm: renesas: rz-du: mipi_dsi: Add dphy_late_init() callback for RZ/V2H(P)

[Laurent Pinchart]

Hi Prabhakar,

Thank you for the patch.

On Mon, May 12, 2025 at 07:23:28PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> Introduce the `dphy_late_init` callback in `rzg2l_mipi_dsi_hw_info` to
> allow additional D-PHY register configurations after enabling data and
> clock lanes. This is required for the RZ/V2H(P) SoC but not for the
> RZ/G2L SoC.
> 
> Modify `rzg2l_mipi_dsi_startup()` to invoke `dphy_late_init` if defined,
> ensuring SoC-specific initialization is performed only when necessary.
> 
> This change prepares for RZ/V2H(P) SoC support while maintaining
> compatibility with existing platforms.
> 
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> ---
> v4->v5:
> - Added Reviewed tag from Biju
> 
> v3->v4:
> - No changes
> 
> v2->v3:
> - No changes
> 
> v1->v2:
> - No changes
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index 55a1c1b043c8..e1ce21a9ddb3 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -34,6 +34,7 @@ struct rzg2l_mipi_dsi;
>  
>  struct rzg2l_mipi_dsi_hw_info {
>  	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, u64 hsfreq_millihz);
> +	void (*dphy_late_init)(struct rzg2l_mipi_dsi *dsi);

As this is called at startup time I would have called it dphy_startup.
Up to you.

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

>  	void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
>  	u32 phy_reg_offset;
>  	u32 link_reg_offset;
> @@ -320,6 +321,9 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  	txsetr = TXSETR_DLEN | TXSETR_NUMLANEUSE(dsi->lanes - 1) | TXSETR_CLEN;
>  	rzg2l_mipi_dsi_link_write(dsi, TXSETR, txsetr);
>  
> +	if (dsi->info->dphy_late_init)
> +		dsi->info->dphy_late_init(dsi);
> +
>  	hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
>  	/*
>  	 * Global timings characteristic depends on high speed Clock Frequency

-- 
Regards,

Laurent Pinchart

Re: [PATCH v5 10/12] drm: renesas: rz-du: mipi_dsi: Add dphy_late_init() callback for RZ/V2H(P)

[Lad, Prabhakar]

Hi Laurent,

Thank you for the review.

On Tue, May 20, 2025 at 3:28 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hi Prabhakar,
>
> Thank you for the patch.
>
> On Mon, May 12, 2025 at 07:23:28PM +0100, Prabhakar wrote:
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > Introduce the `dphy_late_init` callback in `rzg2l_mipi_dsi_hw_info` to
> > allow additional D-PHY register configurations after enabling data and
> > clock lanes. This is required for the RZ/V2H(P) SoC but not for the
> > RZ/G2L SoC.
> >
> > Modify `rzg2l_mipi_dsi_startup()` to invoke `dphy_late_init` if defined,
> > ensuring SoC-specific initialization is performed only when necessary.
> >
> > This change prepares for RZ/V2H(P) SoC support while maintaining
> > compatibility with existing platforms.
> >
> > Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
> > ---
> > v4->v5:
> > - Added Reviewed tag from Biju
> >
> > v3->v4:
> > - No changes
> >
> > v2->v3:
> > - No changes
> >
> > v1->v2:
> > - No changes
> > ---
> >  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 4 ++++
> >  1 file changed, 4 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > index 55a1c1b043c8..e1ce21a9ddb3 100644
> > --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> > @@ -34,6 +34,7 @@ struct rzg2l_mipi_dsi;
> >
> >  struct rzg2l_mipi_dsi_hw_info {
> >       int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, u64 hsfreq_millihz);
> > +     void (*dphy_late_init)(struct rzg2l_mipi_dsi *dsi);
>
> As this is called at startup time I would have called it dphy_startup.
> Up to you.
>
Agreed, I will rename this to dphy_startup_late_init().

Cheers,
Prabhakar

> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
>
> >       void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
> >       u32 phy_reg_offset;
> >       u32 link_reg_offset;
> > @@ -320,6 +321,9 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
> >       txsetr = TXSETR_DLEN | TXSETR_NUMLANEUSE(dsi->lanes - 1) | TXSETR_CLEN;
> >       rzg2l_mipi_dsi_link_write(dsi, TXSETR, txsetr);
> >
> > +     if (dsi->info->dphy_late_init)
> > +             dsi->info->dphy_late_init(dsi);
> > +
> >       hsfreq = DIV_ROUND_CLOSEST_ULL(hsfreq_millihz, MILLI);
> >       /*
> >        * Global timings characteristic depends on high speed Clock Frequency
>
> --
> Regards,
>
> Laurent Pinchart

[PATCH v5 11/12] drm: renesas: rz-du: mipi_dsi: Add function pointers for configuring VCLK and mode validation

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Introduce `dphy_conf_clks` and `dphy_mode_clk_check` callbacks in
`rzg2l_mipi_dsi_hw_info` to configure the VCLK and validate
supported display modes.

On the RZ/V2H(P) SoC, the DSI PLL dividers need to be as accurate as
possible. To ensure compatibility with both RZ/G2L and RZ/V2H(P) SoCs,
function pointers are introduced.

Modify `rzg2l_mipi_dsi_startup()` to use `dphy_conf_clks` for clock
configuration and `rzg2l_mipi_dsi_bridge_mode_valid()` to invoke
`dphy_mode_clk_check` for mode validation.

This change ensures proper operation across different SoC variants
by allowing fine-grained control over clock configuration and mode
validation.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Added Reviewed tag from Biju

v3->v4:
- Replaced KILO with MILLI

v2->v3:
- Replaced unsigned long long with u64

v1->v2:
- No changes
---
 .../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c    | 65 +++++++++++++------
 1 file changed, 45 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index e1ce21a9ddb3..35f0bceac055 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -36,6 +36,10 @@ struct rzg2l_mipi_dsi_hw_info {
 	int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, u64 hsfreq_millihz);
 	void (*dphy_late_init)(struct rzg2l_mipi_dsi *dsi);
 	void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
+	int (*dphy_conf_clks)(struct rzg2l_mipi_dsi *dsi, unsigned long mode_freq,
+			      u64 *hsfreq_millihz);
+	unsigned int (*dphy_mode_clk_check)(struct rzg2l_mipi_dsi *dsi,
+					    unsigned long mode_freq);
 	u32 phy_reg_offset;
 	u32 link_reg_offset;
 	unsigned long max_dclk;
@@ -275,12 +279,39 @@ static void rzg2l_mipi_dsi_dphy_exit(struct rzg2l_mipi_dsi *dsi)
 	reset_control_assert(dsi->rstc);
 }
 
+static int rzg2l_dphy_conf_clks(struct rzg2l_mipi_dsi *dsi, unsigned long mode_freq,
+				u64 *hsfreq_millihz)
+{
+	unsigned long vclk_rate;
+	unsigned int bpp;
+
+	clk_set_rate(dsi->vclk, mode_freq * MILLI);
+	/*
+	 * 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 = hsfreq
+	 */
+	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
+	vclk_rate = clk_get_rate(dsi->vclk);
+	if (vclk_rate != mode_freq * MILLI)
+		dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
+			 mode_freq * MILLI, vclk_rate);
+	*hsfreq_millihz = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(vclk_rate, bpp * MILLI),
+						dsi->lanes);
+
+	return 0;
+}
+
 static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 				  const struct drm_display_mode *mode)
 {
-	unsigned long hsfreq, vclk_rate;
+	unsigned long hsfreq;
 	u64 hsfreq_millihz;
-	unsigned int bpp;
 	u32 txsetr;
 	u32 clstptsetr;
 	u32 lptrnstsetr;
@@ -294,24 +325,9 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
 	if (ret < 0)
 		return ret;
 
-	clk_set_rate(dsi->vclk, mode->clock * MILLI);
-
-	/*
-	 * 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 = hsfreq
-	 */
-	bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
-	vclk_rate = clk_get_rate(dsi->vclk);
-	if (vclk_rate != mode->clock * MILLI)
-		dev_info(dsi->dev, "Requested vclk rate %lu, actual %lu mismatch\n",
-			 mode->clock * MILLI, vclk_rate);
-	hsfreq_millihz = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(vclk_rate, bpp * MILLI), dsi->lanes);
+	ret = dsi->info->dphy_conf_clks(dsi, mode->clock, &hsfreq_millihz);
+	if (ret < 0)
+		goto err_phy;
 
 	ret = dsi->info->dphy_init(dsi, hsfreq_millihz);
 	if (ret < 0)
@@ -618,6 +634,14 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
 	if (mode->clock < dsi->info->min_dclk)
 		return MODE_CLOCK_LOW;
 
+	if (dsi->info->dphy_mode_clk_check) {
+		enum drm_mode_status status;
+
+		status = dsi->info->dphy_mode_clk_check(dsi, mode->clock);
+		if (status != MODE_OK)
+			return status;
+	}
+
 	return MODE_OK;
 }
 
@@ -835,6 +859,7 @@ static void rzg2l_mipi_dsi_remove(struct platform_device *pdev)
 static const struct rzg2l_mipi_dsi_hw_info rzg2l_mipi_dsi_info = {
 	.dphy_init = rzg2l_mipi_dsi_dphy_init,
 	.dphy_exit = rzg2l_mipi_dsi_dphy_exit,
+	.dphy_conf_clks = rzg2l_dphy_conf_clks,
 	.link_reg_offset = 0x10000,
 	.max_dclk = 148500,
 	.min_dclk = 5803,
-- 
2.49.0

[PATCH v5 12/12] drm: renesas: rz-du: mipi_dsi: Add support for LPCLK clock handling

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Add LPCLK clock support in the RZ/G2L MIPI DSI driver via the optional
clock API. This clock is required by some SoCs like RZ/V2H(P) for proper
DPHY configuration, whereas it is absent on others like RZ/G2L.

Introduce a new `lpclk` field in the `rzg2l_mipi_dsi` structure and
conditionally acquire the "lpclk" clock using `devm_clk_get_optional()`
during probe. This allows LPCLK-aware SoCs to pass the clock via device
tree without impacting existing platforms.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4->v5:
- Made use of devm_clk_get_optional() for lpclk
- Added Reviewed tag from Biju

v3->v4
- No changes

v2->v3:
- No changes

v1->v2:
- Added LPCLK as feature flag
---
 drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index 35f0bceac055..98d2f30ae79d 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -62,6 +62,7 @@ struct rzg2l_mipi_dsi {
 	struct drm_bridge *next_bridge;
 
 	struct clk *vclk;
+	struct clk *lpclk;
 
 	enum mipi_dsi_pixel_format format;
 	unsigned int num_data_lanes;
@@ -790,6 +791,10 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
 	if (IS_ERR(dsi->vclk))
 		return PTR_ERR(dsi->vclk);
 
+	dsi->lpclk = devm_clk_get_optional(dsi->dev, "lpclk");
+	if (IS_ERR(dsi->lpclk))
+		return PTR_ERR(dsi->lpclk);
+
 	dsi->rstc = devm_reset_control_get_optional_exclusive(dsi->dev, "rst");
 	if (IS_ERR(dsi->rstc))
 		return dev_err_probe(dsi->dev, PTR_ERR(dsi->rstc),
-- 
2.49.0