diff mbox series

[v2,03/91] dt-bindings: clock: Add a binding for the RPi Firmware clocks

Message ID 69e869b0a79ea17f2cdb79df986409963672495a.1587742492.git-series.maxime@cerno.tech (mailing list archive)
State New, archived
Headers show
Series drm/vc4: Support BCM2711 Display Pipeline | expand

Commit Message

Maxime Ripard April 24, 2020, 3:33 p.m. UTC
The firmware running on the RPi VideoCore can be used to discover and
change the various clocks running in the BCM2711. Since devices will
need to use them through the DT, let's add a pretty simple binding.

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-clk@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

Comments

Rob Herring (Arm) May 11, 2020, 9:47 p.m. UTC | #1
On Fri, Apr 24, 2020 at 05:33:44PM +0200, Maxime Ripard wrote:
> The firmware running on the RPi VideoCore can be used to discover and
> change the various clocks running in the BCM2711. Since devices will
> need to use them through the DT, let's add a pretty simple binding.
> 
> Cc: Michael Turquette <mturquette@baylibre.com>
> Cc: Stephen Boyd <sboyd@kernel.org>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: linux-clk@vger.kernel.org
> Cc: devicetree@vger.kernel.org
> Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> ---
>  Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
> index cec540c052b6..b48ed875eb8e 100644
> --- a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
> +++ b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
> @@ -22,6 +22,25 @@ properties:
>        Phandle to the firmware device's Mailbox.
>        (See: ../mailbox/mailbox.txt for more information)
>  
> +  clocks:
> +    type: object
> +
> +    properties:
> +      compatible:
> +        const: raspberrypi,firmware-clocks
> +
> +      "#clock-cells":
> +        const: 1
> +        description: >
> +          The argument is the ID of the clocks contained by the
> +          firmware messages.

Not really any reason to make this a child node. The parent can be a 
clock provider.

> +
> +    required:
> +      - compatible
> +      - "#clock-cells"
> +
> +    additionalProperties: false
> +
>  required:
>    - compatible
>    - mboxes
> @@ -31,5 +50,10 @@ examples:
>      firmware {
>          compatible = "raspberrypi,bcm2835-firmware", "simple-bus";
>          mboxes = <&mailbox>;
> +
> +        firmware_clocks: clocks {
> +            compatible = "raspberrypi,firmware-clocks";
> +            #clock-cells = <1>;
> +        };
>      };
>  ...
> -- 
> git-series 0.9.1
Maxime Ripard May 13, 2020, 8:13 a.m. UTC | #2
Hi Rob,

On Mon, May 11, 2020 at 04:47:27PM -0500, Rob Herring wrote:
> On Fri, Apr 24, 2020 at 05:33:44PM +0200, Maxime Ripard wrote:
> > The firmware running on the RPi VideoCore can be used to discover and
> > change the various clocks running in the BCM2711. Since devices will
> > need to use them through the DT, let's add a pretty simple binding.
> > 
> > Cc: Michael Turquette <mturquette@baylibre.com>
> > Cc: Stephen Boyd <sboyd@kernel.org>
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: linux-clk@vger.kernel.org
> > Cc: devicetree@vger.kernel.org
> > Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> > ---
> >  Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml | 24 ++++++++++++++++++++++++
> >  1 file changed, 24 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
> > index cec540c052b6..b48ed875eb8e 100644
> > --- a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
> > +++ b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
> > @@ -22,6 +22,25 @@ properties:
> >        Phandle to the firmware device's Mailbox.
> >        (See: ../mailbox/mailbox.txt for more information)
> >  
> > +  clocks:
> > +    type: object
> > +
> > +    properties:
> > +      compatible:
> > +        const: raspberrypi,firmware-clocks
> > +
> > +      "#clock-cells":
> > +        const: 1
> > +        description: >
> > +          The argument is the ID of the clocks contained by the
> > +          firmware messages.
> 
> Not really any reason to make this a child node. The parent can be a 
> clock provider.

This was meant to provide some consistency for that driver. It already has a nod
for the GPIOs exposed through the firmware in the RPi where you could make the
exact same argument, so I guess that, while we shouldn't make the same choices
if we had to design it from scratch, it's more important to keep the same design
choices for a given binding?

Maxime
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
index cec540c052b6..b48ed875eb8e 100644
--- a/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
+++ b/Documentation/devicetree/bindings/arm/bcm/raspberrypi,bcm2835-firmware.yaml
@@ -22,6 +22,25 @@  properties:
       Phandle to the firmware device's Mailbox.
       (See: ../mailbox/mailbox.txt for more information)
 
+  clocks:
+    type: object
+
+    properties:
+      compatible:
+        const: raspberrypi,firmware-clocks
+
+      "#clock-cells":
+        const: 1
+        description: >
+          The argument is the ID of the clocks contained by the
+          firmware messages.
+
+    required:
+      - compatible
+      - "#clock-cells"
+
+    additionalProperties: false
+
 required:
   - compatible
   - mboxes
@@ -31,5 +50,10 @@  examples:
     firmware {
         compatible = "raspberrypi,bcm2835-firmware", "simple-bus";
         mboxes = <&mailbox>;
+
+        firmware_clocks: clocks {
+            compatible = "raspberrypi,firmware-clocks";
+            #clock-cells = <1>;
+        };
     };
 ...