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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 B158EC10DCE for ; Fri, 6 Mar 2020 14:23:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8EA012070E for ; Fri, 6 Mar 2020 14:23:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726498AbgCFOXY (ORCPT ); Fri, 6 Mar 2020 09:23:24 -0500 Received: from foss.arm.com ([217.140.110.172]:34582 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726108AbgCFOXY (ORCPT ); Fri, 6 Mar 2020 09:23:24 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6006C31B; Fri, 6 Mar 2020 06:23:23 -0800 (PST) Received: from bogus (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2B29E3F534; Fri, 6 Mar 2020 06:23:22 -0800 (PST) Date: Fri, 6 Mar 2020 14:23:13 +0000 From: Sudeep Holla To: Peng Fan , Florian Fainelli Cc: "robh+dt@kernel.org" , "viresh.kumar@linaro.org" , dl-linux-imx , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "devicetree@vger.kernel.org" , Sudeep Holla Subject: Re: [PATCH V4 2/2] firmware: arm_scmi: add smc/hvc transport Message-ID: <20200306123442.GA47929@bogus> References: <1583201219-15839-1-git-send-email-peng.fan@nxp.com> <1583201219-15839-3-git-send-email-peng.fan@nxp.com> <20200304103954.GA25004@bogus> <20200304170319.GB44525@bogus> <20200305160613.GA53631@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Fri, Mar 06, 2020 at 08:07:19AM +0000, Peng Fan wrote: > > Subject: Re: [PATCH V4 2/2] firmware: arm_scmi: add smc/hvc transport > > > > On 3/5/20 8:06 AM, Sudeep Holla wrote: > > > On Thu, Mar 05, 2020 at 11:25:35AM +0000, Peng Fan wrote: > > > > > > [...] > > > > > >>> > > >>> Yes, this may fix the issue. However I would like to know if we need > > >>> to support multiple channels/shared memory simultaneously. It is > > >>> fair requirement and may need some work which should be fine. > > >> > > >> Do you have any suggestions? Currently I have not worked out an good > > >> solution. > > >> > > > > > > TBH, I haven't given it a much thought. I would like to know if people > > > are happy with just one SMC channel for SCMI or do they need more ? > > > If they need it, we can try to solve it. Otherwise, what you have will > > > suffice IMO. > > > > On our platforms we have one channel/shared memory area/mailbox > > instance for all standard SCMI protocols, and we have a separate > > channel/shared memory area/mailbox driver instance for a proprietary one. > > They happen to have difference throughput requirements, hence the split. > > OK, when you refer proprietary protocol, do you mean outside the scope of SCMI ? The reason I ask is SCMI allows vendor specific protocols and if you are using other channel for that, it still make sense to add multi-channel support here. > > If I read Peng's submission correctly, it seems to me that the usage model > > described before is still fine. > > Thanks. > > Sudeep, > > Then should I repost with the global mutex added? > Sure, you can send the updated. I will think about adding support for more than one channel and send a patch on top of it if I get around it. Note that I sent PR for v5.7 last earlier this week, so this will be for v5.8 -- Regards, Sudeep