On Wed, Nov 10, 2021 at 09:46:23AM +0000, Conor.Dooley@xxxxxxxxxxxxx wrote: > On 10/11/2021 07:43, Krzysztof Kozlowski wrote: > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > > > On 09/11/2021 14:36, Conor.Dooley@xxxxxxxxxxxxx wrote: > >> On 09/11/2021 12:56, Krzysztof Kozlowski wrote: > >>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > >>> > >>> On 09/11/2021 13:54, Conor.Dooley@xxxxxxxxxxxxx wrote: > >>>> On 08/11/2021 21:16, Krzysztof Kozlowski wrote: > >>>>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > >>>>> > >>>>> On 08/11/2021 16:05, conor.dooley@xxxxxxxxxxxxx wrote: > >>>>>> From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> > >>>>>> > >>>>>> Add device tree bindings for the hardware rng device accessed via > >>>>>> the system services on the Microchip PolarFire SoC. > >>>>>> > >>>>>> Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> > >>>>>> --- > >>>>>> .../bindings/rng/microchip,mpfs-rng.yaml | 31 +++++++++++++++++++ > >>>>>> 1 file changed, 31 insertions(+) > >>>>>> create mode 100644 Documentation/devicetree/bindings/rng/microchip,mpfs-rng.yaml > >>>>>> > >>>>>> diff --git a/Documentation/devicetree/bindings/rng/microchip,mpfs-rng.yaml b/Documentation/devicetree/bindings/rng/microchip,mpfs-rng.yaml > >>>>>> new file mode 100644 > >>>>>> index 000000000000..e8ecb3538a86 > >>>>>> --- /dev/null > >>>>>> +++ b/Documentation/devicetree/bindings/rng/microchip,mpfs-rng.yaml > >>>>>> @@ -0,0 +1,31 @@ > >>>>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > >>>>>> +%YAML 1.2 > >>>>>> +--- > >>>>>> +$id: "http://devicetree.org/schemas/rng/microchip,mpfs-rng.yaml#"; > >>>>>> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"; > >>>>>> + > >>>>>> +title: Microchip MPFS random number generator > >>>>>> + > >>>>>> +maintainers: > >>>>>> + - Conor Dooley <conor.dooley@xxxxxxxxxxxxx> > >>>>>> + > >>>>>> +properties: > >>>>>> + compatible: > >>>>>> + const: microchip,polarfire-soc-rng > >>>>>> + > >>>>>> + syscontroller: > >>>>>> + maxItems: 1 > >>>>>> + description: name of the system controller device node > >>>>> > >>>>> There are several issues with this: > >>>>> 1. You need to describe the type. > >>>>> 2. Description is not helpful (just copying the name of property) and > >>>>> actually misleading because you do not put there the name of device node. > >>>>> 3. What is it? Looks like syscon (or sometimes called sysreg). If yes, > >>>>> please use existing syscon bindings. > >>>> 1 & 2 - Correct, it is bad & I'll write a better description for it. > >>>> 3 - Its a system controller implemented as a mailbox. The syscontroller > >>>> is the mailbox client, which the rng and generic drivers both use. > >>> > >>> I understood that pointed device node is a mailbox, not this node. But > >>> here, what is it here? How do you use it here? > >> The system controller is the means of access to the random number > >> generator. The phandle to the sys controller is provided here so that > >> the rng driver can locate the mailbox client through which it requests > >> random numbers. > > > > I am asking this to understand whether there is a generic or existing > > property which should be used instead. > > > > If I understand correctly, the rng driver needs a mailbox client? > Correct, it needs one. Binding for that is here: > Documentation/devicetree/bindings/soc/microchip/microchip,polarfire-soc-sys-controller.yaml The rng node and others should be a child of the sys controller node. Rob
