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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A5241C54F30 for ; Tue, 27 May 2025 18:18:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:CC:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ZcqNJR+8VtW41JbCbTfke1fL6148OIWbmIsZ4Ld5R8Q=; b=Qzy3eB62oL4lbbyMHYT9tSL9XZ Op8ObJJAYTinK22sv0mscWMy+/IPnISbMrlVC1pjnPYKgcknJw73KasVBwyb19i/99BFWRha2YCWp FO8LoV8IUDdbLhQaxNn41NFKn16NQE34k7antnFogu+7zhzcqPMto7BMttuCwGPiR9gB5/u/FCEY0 tQuNGv8Abzy3IiWwILdBmJVWvY5/mw5PsQ7pMMICKlq6HWjE00lhyXb/GKb/Cm1kojke+5db8688R z6kfwJ8BxXo7XDXqIoSWCM0aQxrH5BuvRzMTban6TiRx4KFZnZsKPRGXthjvH5seA+JtD2zFAyo/Y XZt0V5Gg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uJys9-0000000BLFG-1D9p; Tue, 27 May 2025 18:17:57 +0000 Received: from lelvem-ot01.ext.ti.com ([198.47.23.234]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uJypZ-0000000BKyp-3UGD for linux-arm-kernel@lists.infradead.org; Tue, 27 May 2025 18:15:19 +0000 Received: from lelvem-sh01.itg.ti.com ([10.180.77.71]) by lelvem-ot01.ext.ti.com (8.15.2/8.15.2) with ESMTP id 54RIF4qZ3029528; Tue, 27 May 2025 13:15:04 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1748369704; bh=ZcqNJR+8VtW41JbCbTfke1fL6148OIWbmIsZ4Ld5R8Q=; h=Date:Subject:To:CC:References:From:In-Reply-To; b=LgsIiN8ivuotwzi99cArhQCpWe5Zzmmm4px+h2fS/yv38NvM22Rae7Q3nSC8Ok47I pOe7poeaZYVZF2YSA4LeBzY8WigkzVTZTHiQnc1w1rqGYfDn2EP3+q7DpKmoF/y3M6 MXziNOUsVl6dfmhXregThLQFGcllGI5UOefCBylk= Received: from DFLE102.ent.ti.com (dfle102.ent.ti.com [10.64.6.23]) by lelvem-sh01.itg.ti.com (8.18.1/8.18.1) with ESMTPS id 54RIF4vD2831127 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA256 bits=128 verify=FAIL); Tue, 27 May 2025 13:15:04 -0500 Received: from DFLE114.ent.ti.com (10.64.6.35) by DFLE102.ent.ti.com (10.64.6.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Tue, 27 May 2025 13:15:04 -0500 Received: from lelvem-mr05.itg.ti.com (10.180.75.9) by DFLE114.ent.ti.com (10.64.6.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Tue, 27 May 2025 13:15:04 -0500 Received: from [10.249.141.75] ([10.249.141.75]) by lelvem-mr05.itg.ti.com (8.18.1/8.18.1) with ESMTP id 54RIExut3555206; Tue, 27 May 2025 13:15:00 -0500 Message-ID: <0fe3f172-5a88-4f1d-9eb2-7b748f9f6743@ti.com> Date: Tue, 27 May 2025 23:44:59 +0530 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/2] TI: K3: Switch MCU R5F cluster into Split mode To: Andrew Davis , Nishanth Menon , Beleswar Prasad Padhi CC: , , , , , , , , , , References: <20250522073426.329344-1-b-padhi@ti.com> <20250522155338.gpbcubkvygtju3qc@bagpipe> <5cfaed26-28ec-42dc-b9f6-836869ad3fa3@ti.com> <20250523114822.jrv73frz2wbzdd6d@falsify> <6f4b2271-7249-4285-9fee-1851135e1207@ti.com> Content-Language: en-US From: "Kumar, Udit" In-Reply-To: <6f4b2271-7249-4285-9fee-1851135e1207@ti.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-C2ProcessedOrg: 333ef613-75bf-4e12-a4b1-8e3623f5dcea X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250527_111518_038002_6BDFF5AF X-CRM114-Status: GOOD ( 24.63 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 5/23/2025 6:46 PM, Andrew Davis wrote: > On 5/23/25 6:48 AM, Nishanth Menon wrote: >> On 14:27-20250523, Beleswar Prasad Padhi wrote: >>> Hi Nishanth, >>> >>> On 5/22/2025 9:23 PM, Nishanth Menon wrote: >>>> On 13:04-20250522, Beleswar Padhi wrote: >>>>> Several TI K3 SoCs like J7200, J721E, J721S2, J784S4 and J742S2 >>>>> have a >>>>> R5F cluster in the MCU domain which is configured for LockStep >>>>> mode at >>>>> the moment. Switch this R5F cluster to Split mode by default in all >>>>> corresponding board level DTs to maximize the number of R5F cores. >>>> Why? I can read the patch to understand what you are trying to do, but >>>> the rationale needs to be explained. >>> >>> >>> [..] >> I suggest the following: >> * SoC dts files - use a common standard for remote proc - lockstep makes >>    sense as it is right now >> * Modification to board specific dts files - call them out as board >>    files specific patches to flip over to split mode - while considering >>    the possibilities that users may NOT upgrade kernel and bootloader at >>    the same time and the existence of EFI based dtb handover from >>    bootloader to kernel - which means, kernel should be able to >> handle the >>    same combinations correctly. Also handle the carveouts correctly for >>    the new processors - at least state the strategy - overlays etc.. >> Come >>    to think of it, I think we should fix up the carveout strategy for >>    user programmable remote cores first before attempting all this new >>    processor additions. > > +1 > > The core issue here is that split vs lockstep is a *configuration*, which > means it doesn't belong in DT in the first place. This is the reason > to keep > config out of DT, why should what mode my R5 core starts in be based > on what > board I'm using? It hard-codes what should be configurable decisions. configurable decisions is bootloader build . and you know what you are building then change DT as well. > > Same issue with carveouts, so IMHO all of the: carveouts, mailbox > selection, > timer reserved status, and mode selection belong in an overlay. It > doesn't > fix the issues, but at least it isolates it. > Its usage model, and split mode is enabled at board level. as default, split mode is used, in case lock-step is needed then change DT in custom build too. Also, Patch 1/2 should be posted as different patch. > Andrew > >> * Split out the fixes patches separately out - no reason to mix it up >>    with the rest of the refactoring. >> * Fix your commit messages and subject lines to indicate clearly what is >>    impacted, rationale, backward compatibility status >> >> [1] >> https://lore.kernel.org/all/20250522071828.285462-7-b-padhi@ti.com/#Z31dts:upstream:src:arm64:ti:k3-j7200-mcu-wakeup.dtsi >> [2] https://lore.kernel.org/all/20250522073426.329344-2-b-padhi@ti.com/ >>