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? If it is 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
