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 X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0DD72C352A3 for ; Fri, 7 Feb 2020 11:02:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D877D222C2 for ; Fri, 7 Feb 2020 11:02:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581073321; bh=wzRFLxPbnSe5cu8XeZVGgnId82lJFpJljUiJjz6qjxA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=iivk9gabgyD3pJU7M8v5VI9JvqcBMo7d8a6OZl59noTaZWyh3NVVovX8r4gcdEzjy oO3mz8scEQuI1RMFZvgL8qanIKJ5WJx44jstCZ9inw4x0sUqYWb6uAbtxLEmU3Xupj XlGB7pAZo732MTXgd2EFLyVmNwnkY3lJ0q4e/Mag= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726798AbgBGLCB (ORCPT ); Fri, 7 Feb 2020 06:02:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:49634 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726674AbgBGLCB (ORCPT ); Fri, 7 Feb 2020 06:02:01 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5DFA820720; Fri, 7 Feb 2020 11:02:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581073320; bh=wzRFLxPbnSe5cu8XeZVGgnId82lJFpJljUiJjz6qjxA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=UPDjrC7Q3WIJMCxgLStaBCHc+a/KI6Bhi1wWx61drC9s4XOF526fjXXbrYa+mCMh7 2bRx4aWuOj7TpU313SR7AkcDr8xApmExtnuarHcOK2cQ510+yfwSY1BeocAZXk3z1G rSp0y69hD9PJnaBRd8Spa/h2cr96hnJCJF8ljL0I= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1j01OY-003Vxd-NP; Fri, 07 Feb 2020 11:01:58 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 07 Feb 2020 11:01:58 +0000 From: Marc Zyngier To: Peng Fan Cc: Sudeep Holla , robh+dt@kernel.org, mark.rutland@arm.com, devicetree@vger.kernel.org, f.fainelli@gmail.com, viresh.kumar@linaro.org, linux-kernel@vger.kernel.org, dl-linux-imx , andre.przywara@arm.com, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 1/2] dt-bindings: arm: arm,scmi: add smc/hvc transports In-Reply-To: References: <1580994086-17850-1-git-send-email-peng.fan@nxp.com> <1580994086-17850-2-git-send-email-peng.fan@nxp.com> <7875e2533c4ba23b8ca0a2a296699497@kernel.org> <20200207104736.GB36345@bogus> Message-ID: <455c737109271b0536617e179ffa2606@kernel.org> X-Sender: maz@kernel.org User-Agent: Roundcube Webmail/1.3.8 X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: peng.fan@nxp.com, sudeep.holla@arm.com, robh+dt@kernel.org, mark.rutland@arm.com, devicetree@vger.kernel.org, f.fainelli@gmail.com, viresh.kumar@linaro.org, linux-kernel@vger.kernel.org, linux-imx@nxp.com, andre.przywara@arm.com, linux-arm-kernel@lists.infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On 2020-02-07 10:55, Peng Fan wrote: >> Subject: Re: [PATCH 1/2] dt-bindings: arm: arm,scmi: add smc/hvc >> transports >> >> On Fri, Feb 07, 2020 at 10:08:36AM +0000, Marc Zyngier wrote: >> > On 2020-02-06 13:01, peng.fan@nxp.com wrote: >> > > From: Peng Fan >> > > >> > > SCMI could use SMC/HVC as tranports, so add into devicetree binding >> > > doc. >> > > >> > > Signed-off-by: Peng Fan >> > > --- >> > > Documentation/devicetree/bindings/arm/arm,scmi.txt | 4 +++- >> > > 1 file changed, 3 insertions(+), 1 deletion(-) >> > > >> > > diff --git a/Documentation/devicetree/bindings/arm/arm,scmi.txt >> > > b/Documentation/devicetree/bindings/arm/arm,scmi.txt >> > > index f493d69e6194..03cff8b55a93 100644 >> > > --- a/Documentation/devicetree/bindings/arm/arm,scmi.txt >> > > +++ b/Documentation/devicetree/bindings/arm/arm,scmi.txt >> > > @@ -14,7 +14,7 @@ Required properties: >> > > >> > > The scmi node with the following properties shall be under the >> > > /firmware/ node. >> > > >> > > -- compatible : shall be "arm,scmi" >> > > +- compatible : shall be "arm,scmi" or "arm,scmi-smc" >> > > - mboxes: List of phandle and mailbox channel specifiers. It should >> > > contain >> > > exactly one or two mailboxes, one for transmitting messages("tx") >> > > and another optional for receiving the notifications("rx") if @@ >> > > -25,6 +25,8 @@ The scmi node with the following properties shall be >> > > under the /firmware/ node. >> > > protocol identifier for a given sub-node. >> > > - #size-cells : should be '0' as 'reg' property doesn't have any size >> > > associated with it. >> > > +- arm,smc-id : SMC id required when using smc transports >> > > +- arm,hvc-id : HVC id required when using hvc transports >> > > >> > > Optional properties: >> > >> > Not directly related to DT: Why do we need to distinguish between SMC >> > and HVC? >> >> IIUC you want just one property to get the function ID ? Does that >> align with >> what you are saying ? I wanted to ask the same question and I see no >> need for >> 2 different properties. > > The multiple protocols might use SMC or HVC. Saying > > Protocol@x { > method="smc"; > arm,func-id=<0x....> > }; > Protocol@y { > method="hvc"; > arm,func-id=<0x....> > }; > > With my propose: > > Protocol@x { > arm,smc-id=<0x....> > }; > Protocol@y { > arm,hvc-id=<0x....> > }; > > No need an extra method property to indicate it is smc or hvc. > The driver use take arm,smc-id as SMC, arm,hvc-id as HVC. You're missing the point. I do not want to see different IDs depending on Whether we use HVC and SMC. They *MUST* have the same value, and the right way to enforce this is to disallow any indication of the conduit. An even better thing would be for ARM to mandate the ID, so that vendors can be deprived of their special "value add" once and for all. Thanks, M. -- Jazz is not dead. It just smells funny...