Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <0e72a1a0-611c-9667-866e-a4a1f67f10f6@quicinc.com>
Date:   Tue, 25 Jul 2023 11:01:38 -0700
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101
 Thunderbird/102.6.1
From:   Elliot Berman <quic_eberman@quicinc.com>
Subject: Re: [RFC PATCH 3/4] dt-bindings: power: reset: Document
 arm,psci-vendor-reset
To:     Rob Herring <robh@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
        Lorenzo Pieralisi <lpieralisi@kernel.org>,
        Sebastian Reichel <sre@kernel.org>
CC:     Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        <linux-arm-kernel@lists.infradead.org>, <linux-pm@vger.kernel.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-arm-msm@vger.kernel.org>, <kernel@quicinc.com>,
        Satya Durga Srinivasu Prabhala <quic_satyap@quicinc.com>,
        Melody Olvera <quic_molvera@quicinc.com>,
        "Prasad Sodagudi" <quic_psodagud@quicinc.com>
References: <20230724223057.1208122-1-quic_eberman@quicinc.com>
 <20230724223057.1208122-4-quic_eberman@quicinc.com>
 <20230724232328.GA1101352-robh@kernel.org>
Content-Language: en-US
In-Reply-To: <20230724232328.GA1101352-robh@kernel.org>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk


On 7/24/2023 4:23 PM, Rob Herring wrote:
> On Mon, Jul 24, 2023 at 03:30:53PM -0700, Elliot Berman wrote:
>> Add devicetree bindings for using PSCI SYSTEM_RESET2 with vendor reset  types.
>>
>> Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
>> ---
>>   .../power/reset/arm,psci-vendor-reset.yaml    | 35 +++++++++++++++++++
>>   MAINTAINERS                                   |  1 +
>>   2 files changed, 36 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/power/reset/arm,psci-vendor-reset.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/power/reset/arm,psci-vendor-reset.yaml b/Documentation/devicetree/bindings/power/reset/arm,psci-vendor-reset.yaml
>> new file mode 100644
>> index 000000000000..18b0b8c167a1
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/power/reset/arm,psci-vendor-reset.yaml
>> @@ -0,0 +1,35 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +# Copyright 2023 Qualcomm Innovation Center, Inc. All Rights Reserved.
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/power/reset/arm,psci-vendor-reset.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: PSCI SYSTEM_RESET2 Vendor Resets
>> +
>> +maintainers:
>> +  - Elliot Berman <quic_eberman@quicinc.com>
>> +
>> +description: |
>> +  PSCI SYSTEM_RESET2 supports vendor-defined reset types. This describes
>> +  the conversion of reboot modes to the reset types.
>> +
>> +properties:
>> +  compatible:
>> +    const: arm,psci-vendor-reset
>> +
>> +allOf:
>> +  - $ref: reboot-mode.yaml#
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    firmware {
>> +      psci-vendor-resets {
>> +        compatible = "arm,psci-vendor-reset";
> 
> We already have a node for PSCI, we don't need a second one. You can
> have a separate driver without a separate node.
> 

I could also place the reboot-mode functionality straight into 
drivers/firwmare/psci/? I thought that might be more controversial than 
separate driver, but maybe not?

Mark/Loreno, do you have any concerns to add the reboot-mode driver 
functionality directly in drivers/firmware/psci/psci.c?

Sebastian, do you have any concerns to have this reboot-mode driver 
outside drivers/power/reset/?

>> +        reboot-normal = <0x100>;
> 
> Wouldn't 'normal' be the normal PSCI reset?
> 

Ah, right. I had my head buried in the reboot-mode code when creating 
the example. I can remove from the example.

>> +        reboot-bootloader = <0x101>;
>> +        reboot-fastboot = <0x102>;
>> +      };
>> +    };
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index d516295978a4..2da4c5f1917b 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -16982,6 +16982,7 @@ M:	Mark Rutland <mark.rutland@arm.com>
>>   M:	Lorenzo Pieralisi <lpieralisi@kernel.org>
>>   L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
>>   S:	Maintained
>> +F:	Documentation/devicetree/bindings/power/reset/arm,psci-vendor-reset.yaml
>>   F:	drivers/firmware/psci/
>>   F:	include/linux/psci.h
>>   F:	include/uapi/linux/psci.h
>> -- 
>> 2.41.0
>>