Message-ID: <2e7588e5-9dc5-571f-d7e9-0ee5c89ab39e@canonical.com>
Date:   Fri, 17 Dec 2021 16:47:36 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101
 Thunderbird/91.3.1
Subject: Re: [PATCH v2 06/17] dt-bindings: rng: add bindings for microchip
 mpfs rng
Content-Language: en-US
To:     Conor.Dooley@microchip.com, linus.walleij@linaro.org,
        bgolaszewski@baylibre.com, robh+dt@kernel.org,
        jassisinghbrar@gmail.com, paul.walmsley@sifive.com,
        palmer@dabbelt.com, aou@eecs.berkeley.edu, a.zummo@towertech.it,
        alexandre.belloni@bootlin.com, broonie@kernel.org,
        gregkh@linuxfoundation.org, thierry.reding@gmail.com,
        u.kleine-koenig@pengutronix.de, lee.jones@linaro.org,
        linux-gpio@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
        linux-pwm@vger.kernel.org, linux-riscv@lists.infradead.org,
        linux-crypto@vger.kernel.org, linux-rtc@vger.kernel.org,
        linux-spi@vger.kernel.org, linux-usb@vger.kernel.org
Cc:     geert@linux-m68k.org, bin.meng@windriver.com, heiko@sntech.de,
        Lewis.Hanly@microchip.com, Daire.McNamara@microchip.com,
        Ivan.Griffin@microchip.com, atish.patra@wdc.com
References: <20211217093325.30612-1-conor.dooley@microchip.com>
 <20211217093325.30612-7-conor.dooley@microchip.com>
 <e59a60d5-4397-1f7f-66ab-3dd522e166a0@canonical.com>
 <19cbe2ba-7df5-7c7c-289f-6dc419d9f477@canonical.com>
 <422126ac-ce26-2940-5b4d-fe79a1fa89c5@microchip.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
In-Reply-To: <422126ac-ce26-2940-5b4d-fe79a1fa89c5@microchip.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 17/12/2021 16:22, Conor.Dooley@microchip.com wrote:
> On 17/12/2021 15:07, Krzysztof Kozlowski wrote:
>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>
>> On 17/12/2021 15:53, Krzysztof Kozlowski wrote:
>>> On 17/12/2021 10:33, conor.dooley@microchip.com wrote:
>>>> From: Conor Dooley <conor.dooley@microchip.com>
>>>>
>>>> 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@microchip.com>
>>>> ---
>>>>   .../bindings/rng/microchip,mpfs-rng.yaml      | 29 +++++++++++++++++++
>>>>   1 file changed, 29 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..32cbc37c9292
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/rng/microchip,mpfs-rng.yaml
>>>> @@ -0,0 +1,29 @@
>>>> +# 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@microchip.com>
>>>> +
>>>> +description: |
>>>> +  The hardware random number generator on the Polarfire SoC is
>>>> +  accessed via the mailbox interface provided by the system controller
>>>> +
>>>> +properties:
>>>> +  compatible:
>>>> +    const: microchip,mpfs-rng
>>>> +
>>>> +required:
>>>> +  - compatible
>>>> +
>>>> +additionalProperties: false
>>>> +
>>>> +examples:
>>>> +  - |
>>>> +    hwrandom: hwrandom {
>>>
>>> Three topics:
>>> 1. Node name (as most of others are using): rng
>>> 2. skip the label, not helping in example.
>>> 3. This looks very simple, so I wonder if the bindings are complete. No
>>> IO space/address... How is it going to be instantiated?
>>>
>>
>> OK, now I saw the usage in DTS. I have doubts this makes sense as
>> separate bindings. It looks like integrated part of syscontroller, so
>> maybe make it part of that binding? Or at least add ref to syscontroller
>> bindings that such child is expected.
> Acking the rest of this, re: adding the ref: is what is being done in 
> patch 03/17 insufficient?

Ops, I missed the 03/17. Yeah, it looks it is sufficient and in such
case I think you do not need this patch. The compatible is documented in
03/17. The same for sysserv.


Best regards,
Krzysztof