[PATCH 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[PATCH 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Eric Anholt]

The GPU subsystem node was a workaround to have a central device to
bind V3D and display to.  Following the lead of 246774d17fc0
("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
the subsystem node usage and just create a platform device for the DRM
device to attach to if any of the subsystem devices are present.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 .../bindings/display/brcm,bcm-vc4.txt         |  7 ----
 drivers/gpu/drm/vc4/vc4_drv.c                 | 33 ++++++++++++++-----
 drivers/gpu/drm/vc4/vc4_hvs.c                 |  1 +
 drivers/gpu/drm/vc4/vc4_v3d.c                 |  1 +
 4 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
index 284e2b14cfbe..5fd4717101d6 100644
--- a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
+++ b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
@@ -4,9 +4,6 @@ The VC4 device present on the Raspberry Pi includes a display system
 with HDMI output and the HVS (Hardware Video Scaler) for compositing
 display planes.
 
-Required properties for VC4:
-- compatible:	Should be "brcm,bcm2835-vc4" or "brcm,cygnus-vc4"
-
 Required properties for Pixel Valve:
 - compatible:	Should be one of "brcm,bcm2835-pixelvalve0",
 		  "brcm,bcm2835-pixelvalve1", or "brcm,bcm2835-pixelvalve2"
@@ -153,10 +150,6 @@ v3d: v3d@7ec00000 {
 	interrupts = <1 10>;
 };
 
-vc4: gpu {
-	compatible = "brcm,bcm2835-vc4";
-};
-
 panel: panel {
 	compatible = "ontat,yx700wv03", "simple-panel";
 
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index 7c95ed5c5cac..d282ab7de03a 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -364,22 +364,34 @@ static int vc4_platform_drm_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct of_device_id vc4_of_match[] = {
-	{ .compatible = "brcm,bcm2835-vc4", },
-	{ .compatible = "brcm,cygnus-vc4", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, vc4_of_match);
-
 static struct platform_driver vc4_platform_driver = {
 	.probe		= vc4_platform_drm_probe,
 	.remove		= vc4_platform_drm_remove,
 	.driver		= {
 		.name	= "vc4-drm",
-		.of_match_table = vc4_of_match,
 	},
 };
 
+static bool
+driver_of_table_has_a_match(const struct platform_driver *driver)
+{
+	int i;
+
+	for (i = 0; driver->driver.of_match_table[i].compatible; i++) {
+		const char *compat = driver->driver.of_match_table[i].compatible;
+		struct device_node *node;
+
+		while ((node = of_find_compatible_node(node, NULL, compat))) {
+			if (of_device_is_available(node)) {
+				of_node_put(node);
+				return true;
+			}
+		}
+	}
+
+	return false;
+}
+
 static int __init vc4_drm_register(void)
 {
 	int ret;
@@ -389,6 +401,11 @@ static int __init vc4_drm_register(void)
 	if (ret)
 		return ret;
 
+	if (driver_of_table_has_a_match(&vc4_v3d_driver) ||
+	    driver_of_table_has_a_match(&vc4_hvs_driver)) {
+		platform_device_register_simple("vc4-drm", -1, NULL, 0);
+	}
+
 	return platform_driver_register(&vc4_platform_driver);
 }
 
diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index 2b62fc5b8d85..730813ee74ae 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -262,6 +262,7 @@ static const struct of_device_id vc4_hvs_dt_match[] = {
 	{ .compatible = "brcm,bcm2835-hvs" },
 	{}
 };
+MODULE_DEVICE_TABLE(of, vc4_hvs_dt_match);
 
 struct platform_driver vc4_hvs_driver = {
 	.probe = vc4_hvs_dev_probe,
diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c
index bfc2fa73d2ae..e77e9ebbab4b 100644
--- a/drivers/gpu/drm/vc4/vc4_v3d.c
+++ b/drivers/gpu/drm/vc4/vc4_v3d.c
@@ -459,6 +459,7 @@ static const struct of_device_id vc4_v3d_dt_match[] = {
 	{ .compatible = "brcm,vc4-v3d" },
 	{}
 };
+MODULE_DEVICE_TABLE(of, vc4_v3d_dt_match);
 
 struct platform_driver vc4_v3d_driver = {
 	.probe = vc4_v3d_dev_probe,
-- 
2.17.0

[PATCH 2/3] ARM: dts: bcm283x: Remove the vc4 GPU subsystem node.

[Eric Anholt]

This is no longer required by the DRM driver, and was just a temporary
hack for it.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 arch/arm/boot/dts/bcm283x.dtsi | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/arm/boot/dts/bcm283x.dtsi b/arch/arm/boot/dts/bcm283x.dtsi
index 9d293decf8d3..869bf350d426 100644
--- a/arch/arm/boot/dts/bcm283x.dtsi
+++ b/arch/arm/boot/dts/bcm283x.dtsi
@@ -609,10 +609,6 @@
 			reg = <0x7ec00000 0x1000>;
 			interrupts = <1 10>;
 		};
-
-		vc4: gpu {
-			compatible = "brcm,bcm2835-vc4";
-		};
 	};
 
 	clocks {
-- 
2.17.0

[PATCH 3/3] ARM: dts: cygnus: Remove the vc4 GPU subsystem node.

[Eric Anholt]

This is no longer required by the DRM driver, and was just a temporary
hack for it.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 arch/arm/boot/dts/bcm-cygnus.dtsi | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/arm/boot/dts/bcm-cygnus.dtsi b/arch/arm/boot/dts/bcm-cygnus.dtsi
index 699fdf94d139..258bb3d61582 100644
--- a/arch/arm/boot/dts/bcm-cygnus.dtsi
+++ b/arch/arm/boot/dts/bcm-cygnus.dtsi
@@ -492,10 +492,6 @@
 			status = "disabled";
 		};
 
-		vc4: gpu {
-			compatible = "brcm,cygnus-vc4";
-		};
-
 		gpio_asiu: gpio@180a5000 {
 			compatible = "brcm,cygnus-asiu-gpio";
 			reg = <0x180a5000 0x668>;
-- 
2.17.0

Re: [PATCH 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Stefan Wahren]

Hi Eric,

> Eric Anholt <eric@anholt.net> hat am 10. April 2018 um 01:00 geschrieben:
> 
> 
> The GPU subsystem node was a workaround to have a central device to
> bind V3D and display to.  Following the lead of 246774d17fc0
> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
> the subsystem node usage and just create a platform device for the DRM
> device to attach to if any of the subsystem devices are present.

i didn't test it. Does the code change keep the backward compatibility with older DT?

Re: [PATCH 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Eric Anholt]

[-- Attachment #1: Type: text/plain, Size: 607 bytes --]

Stefan Wahren <stefan.wahren@i2se.com> writes:

> Hi Eric,
>
>> Eric Anholt <eric@anholt.net> hat am 10. April 2018 um 01:00 geschrieben:
>> 
>> 
>> The GPU subsystem node was a workaround to have a central device to
>> bind V3D and display to.  Following the lead of 246774d17fc0
>> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
>> the subsystem node usage and just create a platform device for the DRM
>> device to attach to if any of the subsystem devices are present.
>
> i didn't test it. Does the code change keep the backward compatibility with older DT?

Yes.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]

Re: [PATCH 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Rob Herring]

On Mon, Apr 09, 2018 at 04:00:38PM -0700, Eric Anholt wrote:
> The GPU subsystem node was a workaround to have a central device to
> bind V3D and display to.  Following the lead of 246774d17fc0
> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
> the subsystem node usage and just create a platform device for the DRM
> device to attach to if any of the subsystem devices are present.
> 
> Signed-off-by: Eric Anholt <eric@anholt.net>
> ---
>  .../bindings/display/brcm,bcm-vc4.txt         |  7 ----
>  drivers/gpu/drm/vc4/vc4_drv.c                 | 33 ++++++++++++++-----
>  drivers/gpu/drm/vc4/vc4_hvs.c                 |  1 +
>  drivers/gpu/drm/vc4/vc4_v3d.c                 |  1 +
>  4 files changed, 27 insertions(+), 15 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
> index 284e2b14cfbe..5fd4717101d6 100644
> --- a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
> +++ b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
> @@ -4,9 +4,6 @@ The VC4 device present on the Raspberry Pi includes a display system
>  with HDMI output and the HVS (Hardware Video Scaler) for compositing
>  display planes.
>  
> -Required properties for VC4:
> -- compatible:	Should be "brcm,bcm2835-vc4" or "brcm,cygnus-vc4"
> -
>  Required properties for Pixel Valve:
>  - compatible:	Should be one of "brcm,bcm2835-pixelvalve0",
>  		  "brcm,bcm2835-pixelvalve1", or "brcm,bcm2835-pixelvalve2"
> @@ -153,10 +150,6 @@ v3d: v3d@7ec00000 {
>  	interrupts = <1 10>;
>  };
>  
> -vc4: gpu {
> -	compatible = "brcm,bcm2835-vc4";
> -};
> -
>  panel: panel {
>  	compatible = "ontat,yx700wv03", "simple-panel";
>  
> diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
> index 7c95ed5c5cac..d282ab7de03a 100644
> --- a/drivers/gpu/drm/vc4/vc4_drv.c
> +++ b/drivers/gpu/drm/vc4/vc4_drv.c
> @@ -364,22 +364,34 @@ static int vc4_platform_drm_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> -static const struct of_device_id vc4_of_match[] = {
> -	{ .compatible = "brcm,bcm2835-vc4", },
> -	{ .compatible = "brcm,cygnus-vc4", },
> -	{},
> -};
> -MODULE_DEVICE_TABLE(of, vc4_of_match);
> -
>  static struct platform_driver vc4_platform_driver = {
>  	.probe		= vc4_platform_drm_probe,
>  	.remove		= vc4_platform_drm_remove,
>  	.driver		= {
>  		.name	= "vc4-drm",
> -		.of_match_table = vc4_of_match,
>  	},
>  };
>  
> +static bool
> +driver_of_table_has_a_match(const struct platform_driver *driver)
> +{
> +	int i;
> +

> +	for (i = 0; driver->driver.of_match_table[i].compatible; i++) {
> +		const char *compat = driver->driver.of_match_table[i].compatible;
> +		struct device_node *node;
> +
> +		while ((node = of_find_compatible_node(node, NULL, compat))) {
> +			if (of_device_is_available(node)) {
> +				of_node_put(node);
> +				return true;
> +			}
> +		}
> +	}

All this can be replaced with:

node = of_find_matching_node_and_match(NULL, driver->driver.of_match_table, NULL);
if (of_device_is_available(node)) {
	of_node_put(node);
	return true;
}

> +
> +	return false;
> +}
> +

[PATCH v2 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Eric Anholt]

The GPU subsystem node was a workaround to have a central device to
bind V3D and display to.  Following the lead of 246774d17fc0
("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
the subsystem node usage and just create a platform device for the DRM
device to attach to if any of the subsystem devices are present.

v2: Simplify the DT walking code.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 .../bindings/display/brcm,bcm-vc4.txt         |  7 -----
 drivers/gpu/drm/vc4/vc4_drv.c                 | 29 ++++++++++++++-----
 drivers/gpu/drm/vc4/vc4_hvs.c                 |  1 +
 drivers/gpu/drm/vc4/vc4_v3d.c                 |  1 +
 4 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
index 284e2b14cfbe..5fd4717101d6 100644
--- a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
+++ b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
@@ -4,9 +4,6 @@ The VC4 device present on the Raspberry Pi includes a display system
 with HDMI output and the HVS (Hardware Video Scaler) for compositing
 display planes.
 
-Required properties for VC4:
-- compatible:	Should be "brcm,bcm2835-vc4" or "brcm,cygnus-vc4"
-
 Required properties for Pixel Valve:
 - compatible:	Should be one of "brcm,bcm2835-pixelvalve0",
 		  "brcm,bcm2835-pixelvalve1", or "brcm,bcm2835-pixelvalve2"
@@ -153,10 +150,6 @@ v3d: v3d@7ec00000 {
 	interrupts = <1 10>;
 };
 
-vc4: gpu {
-	compatible = "brcm,bcm2835-vc4";
-};
-
 panel: panel {
 	compatible = "ontat,yx700wv03", "simple-panel";
 
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index 7c95ed5c5cac..13b840b534b8 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -364,22 +364,30 @@ static int vc4_platform_drm_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct of_device_id vc4_of_match[] = {
-	{ .compatible = "brcm,bcm2835-vc4", },
-	{ .compatible = "brcm,cygnus-vc4", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, vc4_of_match);
-
 static struct platform_driver vc4_platform_driver = {
 	.probe		= vc4_platform_drm_probe,
 	.remove		= vc4_platform_drm_remove,
 	.driver		= {
 		.name	= "vc4-drm",
-		.of_match_table = vc4_of_match,
 	},
 };
 
+static bool
+driver_of_table_has_a_match(const struct platform_driver *driver)
+{
+	struct device_node *node;
+
+	node = of_find_matching_node_and_match(NULL,
+					       driver->driver.of_match_table,
+					       NULL);
+	if (of_device_is_available(node)) {
+		of_node_put(node);
+		return true;
+	}
+
+	return false;
+}
+
 static int __init vc4_drm_register(void)
 {
 	int ret;
@@ -389,6 +397,11 @@ static int __init vc4_drm_register(void)
 	if (ret)
 		return ret;
 
+	if (driver_of_table_has_a_match(&vc4_v3d_driver) ||
+	    driver_of_table_has_a_match(&vc4_hvs_driver)) {
+		platform_device_register_simple("vc4-drm", -1, NULL, 0);
+	}
+
 	return platform_driver_register(&vc4_platform_driver);
 }
 
diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index 2b62fc5b8d85..730813ee74ae 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -262,6 +262,7 @@ static const struct of_device_id vc4_hvs_dt_match[] = {
 	{ .compatible = "brcm,bcm2835-hvs" },
 	{}
 };
+MODULE_DEVICE_TABLE(of, vc4_hvs_dt_match);
 
 struct platform_driver vc4_hvs_driver = {
 	.probe = vc4_hvs_dev_probe,
diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c
index bfc2fa73d2ae..e77e9ebbab4b 100644
--- a/drivers/gpu/drm/vc4/vc4_v3d.c
+++ b/drivers/gpu/drm/vc4/vc4_v3d.c
@@ -459,6 +459,7 @@ static const struct of_device_id vc4_v3d_dt_match[] = {
 	{ .compatible = "brcm,vc4-v3d" },
 	{}
 };
+MODULE_DEVICE_TABLE(of, vc4_v3d_dt_match);
 
 struct platform_driver vc4_v3d_driver = {
 	.probe = vc4_v3d_dev_probe,
-- 
2.17.0

Re: [PATCH v2 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Rob Herring]

On Mon, Apr 16, 2018 at 12:25 PM, Eric Anholt <eric@anholt.net> wrote:
> The GPU subsystem node was a workaround to have a central device to
> bind V3D and display to.  Following the lead of 246774d17fc0
> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
> the subsystem node usage and just create a platform device for the DRM
> device to attach to if any of the subsystem devices are present.
>
> v2: Simplify the DT walking code.

> +static bool
> +driver_of_table_has_a_match(const struct platform_driver *driver)
> +{
> +       struct device_node *node;
> +
> +       node = of_find_matching_node_and_match(NULL,
> +                                              driver->driver.of_match_table,
> +                                              NULL);
> +       if (of_device_is_available(node)) {
> +               of_node_put(node);

You need to put the node regardless.

> +               return true;
> +       }
> +
> +       return false;
> +}

[PATCH v3 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Eric Anholt]

The GPU subsystem node was a workaround to have a central device to
bind V3D and display to.  Following the lead of 246774d17fc0
("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
the subsystem node usage and just create a platform device for the DRM
device to attach to if any of the subsystem devices are present.

v2: Simplify the DT walking code.
v3: Always put the node.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 .../bindings/display/brcm,bcm-vc4.txt         |  7 -----
 drivers/gpu/drm/vc4/vc4_drv.c                 | 28 +++++++++++++------
 drivers/gpu/drm/vc4/vc4_hvs.c                 |  1 +
 drivers/gpu/drm/vc4/vc4_v3d.c                 |  1 +
 4 files changed, 22 insertions(+), 15 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
index 284e2b14cfbe..5fd4717101d6 100644
--- a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
+++ b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
@@ -4,9 +4,6 @@ The VC4 device present on the Raspberry Pi includes a display system
 with HDMI output and the HVS (Hardware Video Scaler) for compositing
 display planes.
 
-Required properties for VC4:
-- compatible:	Should be "brcm,bcm2835-vc4" or "brcm,cygnus-vc4"
-
 Required properties for Pixel Valve:
 - compatible:	Should be one of "brcm,bcm2835-pixelvalve0",
 		  "brcm,bcm2835-pixelvalve1", or "brcm,bcm2835-pixelvalve2"
@@ -153,10 +150,6 @@ v3d: v3d@7ec00000 {
 	interrupts = <1 10>;
 };
 
-vc4: gpu {
-	compatible = "brcm,bcm2835-vc4";
-};
-
 panel: panel {
 	compatible = "ontat,yx700wv03", "simple-panel";
 
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index 7c95ed5c5cac..e8ba9e7c71d2 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -364,22 +364,29 @@ static int vc4_platform_drm_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct of_device_id vc4_of_match[] = {
-	{ .compatible = "brcm,bcm2835-vc4", },
-	{ .compatible = "brcm,cygnus-vc4", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, vc4_of_match);
-
 static struct platform_driver vc4_platform_driver = {
 	.probe		= vc4_platform_drm_probe,
 	.remove		= vc4_platform_drm_remove,
 	.driver		= {
 		.name	= "vc4-drm",
-		.of_match_table = vc4_of_match,
 	},
 };
 
+static bool
+driver_of_table_has_a_match(const struct platform_driver *driver)
+{
+	struct device_node *node;
+	bool ret;
+
+	node = of_find_matching_node_and_match(NULL,
+					       driver->driver.of_match_table,
+					       NULL);
+	ret = of_device_is_available(node);
+	of_node_put(node);
+
+	return ret;
+}
+
 static int __init vc4_drm_register(void)
 {
 	int ret;
@@ -389,6 +396,11 @@ static int __init vc4_drm_register(void)
 	if (ret)
 		return ret;
 
+	if (driver_of_table_has_a_match(&vc4_v3d_driver) ||
+	    driver_of_table_has_a_match(&vc4_hvs_driver)) {
+		platform_device_register_simple("vc4-drm", -1, NULL, 0);
+	}
+
 	return platform_driver_register(&vc4_platform_driver);
 }
 
diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index 2b62fc5b8d85..730813ee74ae 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -262,6 +262,7 @@ static const struct of_device_id vc4_hvs_dt_match[] = {
 	{ .compatible = "brcm,bcm2835-hvs" },
 	{}
 };
+MODULE_DEVICE_TABLE(of, vc4_hvs_dt_match);
 
 struct platform_driver vc4_hvs_driver = {
 	.probe = vc4_hvs_dev_probe,
diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c
index bfc2fa73d2ae..e77e9ebbab4b 100644
--- a/drivers/gpu/drm/vc4/vc4_v3d.c
+++ b/drivers/gpu/drm/vc4/vc4_v3d.c
@@ -459,6 +459,7 @@ static const struct of_device_id vc4_v3d_dt_match[] = {
 	{ .compatible = "brcm,vc4-v3d" },
 	{}
 };
+MODULE_DEVICE_TABLE(of, vc4_v3d_dt_match);
 
 struct platform_driver vc4_v3d_driver = {
 	.probe = vc4_v3d_dev_probe,
-- 
2.17.0

Re: [PATCH v3 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Rob Herring]

On Mon, Apr 16, 2018 at 5:52 PM, Eric Anholt <eric@anholt.net> wrote:
> The GPU subsystem node was a workaround to have a central device to
> bind V3D and display to.  Following the lead of 246774d17fc0
> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
> the subsystem node usage and just create a platform device for the DRM
> device to attach to if any of the subsystem devices are present.
>
> v2: Simplify the DT walking code.
> v3: Always put the node.
>
> Signed-off-by: Eric Anholt <eric@anholt.net>
> ---
>  .../bindings/display/brcm,bcm-vc4.txt         |  7 -----
>  drivers/gpu/drm/vc4/vc4_drv.c                 | 28 +++++++++++++------
>  drivers/gpu/drm/vc4/vc4_hvs.c                 |  1 +
>  drivers/gpu/drm/vc4/vc4_v3d.c                 |  1 +
>  4 files changed, 22 insertions(+), 15 deletions(-)

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH v3 1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.

[Eric Anholt]

[-- Attachment #1: Type: text/plain, Size: 1162 bytes --]

Rob Herring <robh+dt@kernel.org> writes:

> On Mon, Apr 16, 2018 at 5:52 PM, Eric Anholt <eric@anholt.net> wrote:
>> The GPU subsystem node was a workaround to have a central device to
>> bind V3D and display to.  Following the lead of 246774d17fc0
>> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
>> the subsystem node usage and just create a platform device for the DRM
>> device to attach to if any of the subsystem devices are present.
>>
>> v2: Simplify the DT walking code.
>> v3: Always put the node.
>>
>> Signed-off-by: Eric Anholt <eric@anholt.net>
>> ---
>>  .../bindings/display/brcm,bcm-vc4.txt         |  7 -----
>>  drivers/gpu/drm/vc4/vc4_drv.c                 | 28 +++++++++++++------
>>  drivers/gpu/drm/vc4/vc4_hvs.c                 |  1 +
>>  drivers/gpu/drm/vc4/vc4_v3d.c                 |  1 +
>>  4 files changed, 22 insertions(+), 15 deletions(-)
>
> Reviewed-by: Rob Herring <robh@kernel.org>

Unfortunately, on further testing, this ends up broken.  My guess is
that our new platform device isn't on the same bus, so we don't get our
dma-ranges translation when we use drm->dev, and that breaks caching
behavior.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]