From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0926EECAAA1 for ; Thu, 27 Oct 2022 19:56:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236742AbiJ0Tz7 (ORCPT ); Thu, 27 Oct 2022 15:55:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236719AbiJ0Tzz (ORCPT ); Thu, 27 Oct 2022 15:55:55 -0400 Received: from mail-qk1-x733.google.com (mail-qk1-x733.google.com [IPv6:2607:f8b0:4864:20::733]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15D2B4150A for ; Thu, 27 Oct 2022 12:55:54 -0700 (PDT) Received: by mail-qk1-x733.google.com with SMTP id 8so1919934qka.1 for ; Thu, 27 Oct 2022 12:55:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=phTE8Hb2ngpgKiU4qEw9Lxs4Tg0Q1IriLkNiuUxWbrA=; b=SLiZgtBtLeK+zXz2D/eNY1D1zV3xsgNeksFqjPCbsKNbPzMla/jRUDugiePENX73ip P/2mXeFdNEpaJrZlcZUZvNsyAuPAnIrZAiC5ALBMHFJUrQ0Rb9CQYk773GYs0q3iGqvh B2WM4HerpmMxEQiSda7hzKWhdXNhkW38WHwUdtBmW2ffVcRHwAL61jvG1h9IwIDmO2vX oor1QPHbN8jVVVS0IvkJKvwW6oaLAZuh1ob7nE2lo9Ot33KloW/Lef7rBSbbH2rf8d7d aE64Y6HQZxtQsonfMDH1nnrRRvM9sIZvb5UWzuvgLq8ZtAJuCbLn9llNBDxt4LydG89z apDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=phTE8Hb2ngpgKiU4qEw9Lxs4Tg0Q1IriLkNiuUxWbrA=; b=or1KQWfIP7Vfnof4Yppblzf/lgty1dMnfJPsv7afO4IAI0rmNcygqsDuLye+0XrEHA +wNX/T1Idxe1sK8hIS6xJT0VgJJdfeI9/rXpolWF9m9PF4Ou5UD7jj9tmiQh4dO+cZLd Ss2OWcHMqxizBTmMcC/0abeA4l31xUeszj++LWrV5YG5rDqj7WYJNJM3zyvcvCbyXVbk iWntPCjnULZiMR4UYhMVQys/dzp38oUMqc59lbi+q3vusHctTqnJ7ma59OGPDDLyPWQs XaZ4FysgavJPHgYgKSxGeDLTG8WR+gKIIkPa+8Mk3SIf6QDSK/NvlxKTBmefogxozapq J9Jg== X-Gm-Message-State: ACrzQf1ck869EqRy8Q/QGz2R0chUwWcgU9Ly7O24nV46bcze71tS+fmz 4PRFKP7PqEe7XvYekCb55RpsTA== X-Google-Smtp-Source: AMsMyM5FXOg6GzFfIF0AuRgweoogKXQKTmdDgZJ2PVbtcQn8m9jGg9sXOm3QaqOPYu4qR9rZ5hVLrg== X-Received: by 2002:a37:b041:0:b0:6eb:cc8c:e9a9 with SMTP id z62-20020a37b041000000b006ebcc8ce9a9mr34662885qke.573.1666900553202; Thu, 27 Oct 2022 12:55:53 -0700 (PDT) Received: from [192.168.1.11] ([64.57.193.93]) by smtp.gmail.com with ESMTPSA id n14-20020a05620a294e00b006eed094dcdasm1585036qkp.70.2022.10.27.12.55.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 27 Oct 2022 12:55:52 -0700 (PDT) Message-ID: <79673829-a079-201f-91e1-790eb7cc3a4b@linaro.org> Date: Thu, 27 Oct 2022 15:55:50 -0400 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.0 Subject: Re: [PATCH v5 02/13] dt-bindings: Add binding for gunyah hypervisor Content-Language: en-US To: Elliot Berman , Rob Herring Cc: Bjorn Andersson , Krzysztof Kozlowski , Murali Nalajala , Trilok Soni , Srivatsa Vaddagiri , Carl van Schaik , Prakruthi Deepak Heragu , Andy Gross , Dmitry Baryshkov , Jassi Brar , linux-arm-kernel@lists.infradead.org, Mark Rutland , Lorenzo Pieralisi , Sudeep Holla , Marc Zyngier , Jonathan Corbet , Will Deacon , Catalin Marinas , Arnd Bergmann , Greg Kroah-Hartman , devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org References: <20221011000840.289033-1-quic_eberman@quicinc.com> <20221011000840.289033-3-quic_eberman@quicinc.com> <20221012155645.GA2173829-robh@kernel.org> <75ef3cc5-3b19-9eab-b3eb-56fa254d92bd@quicinc.com> From: Krzysztof Kozlowski In-Reply-To: <75ef3cc5-3b19-9eab-b3eb-56fa254d92bd@quicinc.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 27/10/2022 12:17, Elliot Berman wrote: > Hi Rob, > > On 10/26/2022 2:16 PM, Rob Herring wrote: >> On Thu, Oct 13, 2022 at 6:59 PM Elliot Berman wrote: >>> >>> >>> On 10/12/2022 8:56 AM, Rob Herring wrote: >>>> On Mon, Oct 10, 2022 at 05:08:29PM -0700, Elliot Berman wrote: >>>>> When Linux is booted as a guest under the Gunyah hypervisor, the Gunyah >>>>> Resource Manager applies a devicetree overlay describing the virtual >>>>> platform configuration of the guest VM, such as the message queue >>>>> capability IDs for communicating with the Resource Manager. This >>>>> information is not otherwise discoverable by a VM: the Gunyah hypervisor >>>>> core does not provide a direct interface to discover capability IDs nor >>>>> a way to communicate with RM without having already known the >>>>> corresponding message queue capability ID. Add the DT bindings that >>>>> Gunyah adheres for the hypervisor node and message queues. >>>>> >>>>> Signed-off-by: Elliot Berman >>>>> --- >>>>> .../bindings/firmware/gunyah-hypervisor.yaml | 87 +++++++++++++++++++ >>>>> MAINTAINERS | 1 + >>>>> 2 files changed, 88 insertions(+) >>>>> create mode 100644 Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml >>>>> >>>>> diff --git a/Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml b/Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml >>>>> new file mode 100644 >>>>> index 000000000000..f0a14101e2fd >>>>> --- /dev/null >>>>> +++ b/Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml >>>>> @@ -0,0 +1,87 @@ >>>>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) >>>>> +%YAML 1.2 >>>>> +--- >>>>> +$id: http://devicetree.org/schemas/firmware/gunyah-hypervisor.yaml# >>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml# >>>>> + >>>>> +title: Gunyah Hypervisor >>>>> + >>>>> +maintainers: >>>>> + - Murali Nalajala >>>>> + - Elliot Berman >>>>> + >>>>> +description: |+ >>>>> + On systems which support devicetree, Gunyah generates and overlays a deviceetree overlay which >>>> >>>> How you end up with the node (applying an overlay) is not relavent to >>>> the binding. >>>> >>>>> + describes the basic configuration of the hypervisor. Virtual machines use this information to determine >>>>> + the capability IDs of the message queues used to communicate with the Gunyah Resource Manager. >>>> >>>> Wrap at 80. That is the coding standard still though 100 is deemed >>>> allowed. And yamllint only complains at 110 because I didn't care to fix >>>> everyones lines over 100. >>>> >>>>> + See also: https://github.com/quic/gunyah-resource-manager/blob/develop/src/vm_creation/dto_construct.c >>>>> + >>>>> +properties: >>>>> + compatible: >>>>> + items: >>>>> + - const: gunyah-hypervisor-1.0 >>>>> + - const: gunyah-hypervisor >>>> >>>> 2 compatibles implies a difference between the 2. What's the difference? >>>> Where does '1.0' come from? >>>> >>> >>> There's no difference. I thought the convention was to have >>> device-specific compatible and the generic compatible. "device-specific" >>> here would be specific to version of Gunyah since it's software. >> >> No, that's just what people do because "vendor,new-soc", >> "vendor,old-soc" seems to bother them for some reason. At the end of >> the day, it's just a string identifier that means something. If >> there's no difference in that 'something', then there is no point in >> having more than one string. >> >> You only need something specific enough to discover the rest from the >> firmware. When that changes, then you add a new compatible. Of course, >> if you want existing OSs to work, then better not change the >> compatible. >> > > Thanks for the info, I'll drop the "-1.0" suffix. You still did not answer from where does 1.0 come from... Compatibles are usually expected to be specific. Best regards, Krzysztof