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 > If it is a mailbox client, then there is a property: "mboxes". Use this one > (look for existing bindings, e.g. > Documentation/devicetree/bindings/firmware/arm,scmi.yaml). > > > Best regards, > Krzysztof >