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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 19FB9C55ABD for ; Tue, 10 Nov 2020 17:44:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B6339207D3 for ; Tue, 10 Nov 2020 17:44:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="UbLB04Un" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729630AbgKJRo3 (ORCPT ); Tue, 10 Nov 2020 12:44:29 -0500 Received: from mail.kernel.org ([198.145.29.99]:49916 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726400AbgKJRo3 (ORCPT ); Tue, 10 Nov 2020 12:44:29 -0500 Received: from kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com (unknown [163.114.132.7]) (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 C85572076E; Tue, 10 Nov 2020 17:44:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605030269; bh=A8zVlL/t8rEgJcCsmw7gpjI9i3zi4wwuuGk60Hugyas=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=UbLB04UnnxKK0p2UVvqQ0Ie8sd1CoS2ruISHbFY4fob4DtEW2qWY4N1msGaBkC8QH 9ibJyEXkx1j+5+ZogE7KaEqrSW2NmuTKd6GyHjC6gZDLlw0aqIusmbXTdUx6JfG+qA QM1U2sp5bv+ZsDPpXVDDRmOQi9HEpiwTIrYK1Jkc= Date: Tue, 10 Nov 2020 09:44:27 -0800 From: Jakub Kicinski To: Loic Poulain , Manivannan Sadhasivam Cc: David Miller , Bjorn Andersson , cjhuang@codeaurora.org, Network Development Subject: Re: [PATCH v2 0/5] net: qrtr: Add distant node support Message-ID: <20201110094427.5ffb1d1b@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: References: <1604684010-24090-1-git-send-email-loic.poulain@linaro.org> <20201107162640.357a2b6f@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <20201109103946.4598e667@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, 10 Nov 2020 10:03:29 +0100 Loic Poulain wrote: > On Mon, 9 Nov 2020 at 19:39, Jakub Kicinski wrote: > > > > On Mon, 9 Nov 2020 09:49:24 +0100 Loic Poulain wrote: > > > > Looks like patch 1 is a bug fix and patches 2-5 add a new feature. > > > > Is that correct? > > > > > > That's correct, though strictly speaking 2-5 are also bug fix since remote node > > > communication is supposed to be supported in QRTR to be compatible with > > > other implementations (downstream or private implementations). > > > > Is there a spec we can quote to support that, or is QRTR purely > > a vendor interface? > > There is no public spec AFAIK, this is a vendor interface. > > > What's the end user issue that we're solving? After firmware upgrade > > things stop working? Things don't work on HW platforms on which this > > was not tested? Don't work on new HW platforms? > > QRTR is usually something used in SoC context as communication > protocol for accessing the differents IPs (modem, WiFi, DSP, etc) > around the CPU. In that case, these components (nodes), identified > with a 'node ID', are directly reachable by the CPU (QRTR over shared > memory). This case is not impacted by the series, all nodes beeing CPU > immediate neighbours. > > But today QRTR is no more a ARCH_QCOM thing only, It is also exposed > as communication channel for QCOM based wireless modules (e.g. SDX55 > modem), over PCIe/MHI. In that case, the host is only connected to the > Modem CPU QRTR endpoint that in turn gives access to other embedded > Modem endpoints, acting as a gateway/bridge for accessing > non-immediate nodes from the host. currently, this case is not working > and the series fix it. > > However, AFAIK, the only device would request this support is the > SDX55 PCIe module, that just landed in mhi-next. So I assume it's fine > if the related part of the series targets net-next. Thanks! Sounds like net-next will work just fine, but won't you need these changes in mhi-next, then? In which case you should send a pull request based on Linus' tree so that both Mani and netdev can pull it in. Mani, WDYT?