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 56554C6FD1F for ; Tue, 26 Mar 2024 17:15:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=mjpfSEWXI1d1IbZfY494hH9QuDDj6tlPEfbiQDhm5G8=; b=XFYX2LkYfg87av UPoW9yfcwD1JtI/IgPs6FmF3amy/7Lj77/E7XraI6D18/ruP3Pa6aYPTwu/vB/mqYbKHnodbHE8UZ oO7ZFkDckjGo91TLnFwQu2Rt0hpPQpDkgdkAgIEFr8SChy62u0rGnZJZINZbc25+3rlyZ0cmkw0+x o5uDiQEW4Tt1oyY3xYoG72a8leF6wG+5kQo239MpyNtFp6EcxlkfYM71cU3DCrSDkVcBYeucbOH/A GXZ0vlqHNB394cx8ul1/VccnMy7bi+mYhel3xvD1hh8guxRmy0mfxOCPWhRyYs7p80y+PO0ZccgXZ xMPsmVoATbbslRtCKTjQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rpAOF-00000005gNp-1XGW; Tue, 26 Mar 2024 17:15:11 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rpANw-00000005gIf-3DRm for linux-arm-kernel@lists.infradead.org; Tue, 26 Mar 2024 17:15:07 +0000 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 8D96A2F4; Tue, 26 Mar 2024 10:15:23 -0700 (PDT) Received: from e130802.arm.com (e130802.arm.com [10.1.39.41]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3B3213F64C; Tue, 26 Mar 2024 10:14:47 -0700 (PDT) Date: Tue, 26 Mar 2024 17:14:38 +0000 From: Abdellatif El Khlifi To: Mathieu Poirier Cc: Abdellatif El Khlifi , Sudeep Holla , Bjorn Andersson , Rob Herring , Liviu Dudau , Lorenzo Pieralisi , Krzysztof Kozlowski , Conor Dooley , Drew.Reed@arm.com, Adam.Johnston@arm.com, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-remoteproc@vger.kernel.org Subject: Re: [PATCH 1/3] remoteproc: Add Arm remoteproc driver Message-ID: <20240326171438.GA56238@e130802.arm.com> References: <20240311114442.GA82865@e130802.arm.com> <20240312173252.GA38992@e130802.arm.com> <20240313171756.GA82165@e130802.arm.com> <20240325171339.GA368569@e130802.arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240326_101452_957353_61430B04 X-CRM114-Status: GOOD ( 40.47 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Mathieu, > > > > > > > > > > This is an initial patchset for allowing to turn on and off the remote processor. > > > > > > > > > > The FW is already loaded before the Corstone-1000 SoC is powered on and this > > > > > > > > > > is done through the FPGA board bootloader in case of the FPGA target. Or by the Corstone-1000 FVP model > > > > > > > > > > (emulator). > > > > > > > > > > > > > > > > > > > >From the above I take it that booting with a preloaded firmware is a > > > > > > > > > scenario that needs to be supported and not just a temporary stage. > > > > > > > > > > > > > > > > The current status of the Corstone-1000 SoC requires that there is > > > > > > > > a preloaded firmware for the external core. Preloading is done externally > > > > > > > > either through the FPGA bootloader or the emulator (FVP) before powering > > > > > > > > on the SoC. > > > > > > > > > > > > > > > > > > > > > > Ok > > > > > > > > > > > > > > > Corstone-1000 will be upgraded in a way that the A core running Linux is able > > > > > > > > to share memory with the remote core and also being able to access the remote > > > > > > > > core memory so Linux can copy the firmware to. This HW changes are still > > > > > > > > This is why this patchset is relying on a preloaded firmware. And it's the step 1 > > > > > > > > of adding remoteproc support for Corstone. > > > > > > > > > > > > > > > > > > > > > > Ok, so there is a HW problem where A core and M core can't see each other's > > > > > > > memory, preventing the A core from copying the firmware image to the proper > > > > > > > location. > > > > > > > > > > > > > > When the HW is fixed, will there be a need to support scenarios where the > > > > > > > firmware image has been preloaded into memory? > > > > > > > > > > > > No, this scenario won't apply when we get the HW upgrade. No need for an > > > > > > external entity anymore. The firmware(s) will all be files in the linux filesystem. > > > > > > > > > > > > > > > > Very well. I am willing to continue with this driver but it does so little that > > > > > I wonder if it wouldn't simply be better to move forward with upstreaming when > > > > > the HW is fixed. The choice is yours. > > > > > > > > > > > > > I think Robin has raised few points that need clarification. I think it was > > > > done as part of DT binding patch. I share those concerns and I wanted to > > > > reaching to the same concerns by starting the questions I asked on corstone > > > > device tree changes. > > > > > > > > > > I also agree with Robin's point of view. Proceeding with an initial > > > driver with minimal functionality doesn't preclude having complete > > > bindings. But that said and as I pointed out, it might be better to > > > wait for the HW to be fixed before moving forward. > > > > We checked with the HW teams. The missing features will be implemented but > > this will take time. > > > > The foundation driver as it is right now is still valuable for people wanting to > > know how to power control Corstone external systems in a future proof manner > > (even in the incomplete state). We prefer to address all the review comments > > made so it can be merged. This includes making the DT binding as complete as > > possible as you advised. Then, once the HW is ready, I'll implement the comms > > and the FW reload part. Is that OK please ? > > > > I'm in agreement with that plan as long as we agree the current > preloaded heuristic is temporary and is not a valid long term > scenario. Yes, that's the plan, no problem. Cheers, Abdellatif _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel