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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D90F0C433F5 for ; Tue, 19 Oct 2021 13:20:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B82F261378 for ; Tue, 19 Oct 2021 13:20:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235828AbhJSNWW (ORCPT ); Tue, 19 Oct 2021 09:22:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:58428 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231563AbhJSNWV (ORCPT ); Tue, 19 Oct 2021 09:22:21 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7AAF1610E7; Tue, 19 Oct 2021 13:20:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1634649608; bh=xGEIDfi1JKH3eqvvi6gZj8PD5RM7Y9UpbqwvaVzs/Wo=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=m49h4VW6MoCd4zMCdev/m86jNWKuJXK1Pvme1TuC3s7014zUBOYNyR0oDjYStrz6h HcGQ3SsdxazHbz+uU7eyGedc0n58OXoh9hWtnzJP3mFb+T4F8bC5TBftgPhjALJsAa UmT5EKpoEXNh9lU4lG/uDCByq5+sY8uHY9gQXCTB0+YqyElgM9IoBOUMHVRdcYcAY2 aKssdW17ZWuW9g5wd+XRVoBk9ndAmAVWY0/O7y992m/ewf6T1/8JSCe2zbkzBaVuxR VvLaA4qhc0hOINVPN8nU58AT/0VOW96gBOkPway5Lz7KAYBR/CnvcGU430bvMNKmQO kojxFIc+kLPmA== Received: by mail-ed1-f45.google.com with SMTP id a25so12763134edx.8; Tue, 19 Oct 2021 06:20:08 -0700 (PDT) X-Gm-Message-State: AOAM531yp/c+Y2E8ypiSWONOxsy3RlCTKCTn50xiIc/6aUtTVkpsthy6 /1aBN92EBvYuF7BgRo8GYo+IAXLMlHY1QRdynQ== X-Google-Smtp-Source: ABdhPJwuCT2accakT1n8HM9H8FZqhzJoiBD2H7LJdGtKC3BtNmJwjl0n52dVamz1Jg6FtFki6Znb7OXYl78LT011sgY= X-Received: by 2002:a17:906:c350:: with SMTP id ci16mr36562486ejb.466.1634649595458; Tue, 19 Oct 2021 06:19:55 -0700 (PDT) MIME-Version: 1.0 References: <20211011141733.3999-1-stephan@gerhold.net> <20211011141733.3999-4-stephan@gerhold.net> In-Reply-To: From: Rob Herring Date: Tue, 19 Oct 2021 08:19:42 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH net-next v2 3/4] dt-bindings: net: Add schema for Qualcomm BAM-DMUX To: Stephan Gerhold Cc: "David S. Miller" , Jakub Kicinski , Loic Poulain , Sergey Ryazanov , Johannes Berg , Bjorn Andersson , Andy Gross , Vinod Koul , Aleksander Morgado , netdev , linux-arm-msm , "open list:DMA GENERIC OFFLOAD ENGINE SUBSYSTEM" , devicetree@vger.kernel.org, "linux-kernel@vger.kernel.org" , phone-devel@vger.kernel.org, "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS , Hans de Goede , Andy Shevchenko ," <~postmarketos/upstreaming@lists.sr.ht>, Jeffrey Hugo Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Tue, Oct 19, 2021 at 2:03 AM Stephan Gerhold wrote: > > On Mon, Oct 18, 2021 at 03:22:25PM -0500, Rob Herring wrote: > > On Mon, Oct 11, 2021 at 04:17:35PM +0200, Stephan Gerhold wrote: > > > The BAM Data Multiplexer provides access to the network data channels of > > > modems integrated into many older Qualcomm SoCs, e.g. Qualcomm MSM8916 or > > > MSM8974. It is built using a simple protocol layer on top of a DMA engine > > > (Qualcomm BAM) and bidirectional interrupts to coordinate power control. > > > > > > The device tree node combines the incoming interrupt with the outgoing > > > interrupts (smem-states) as well as the two DMA channels, which allows > > > the BAM-DMUX driver to request all necessary resources. > > > > > > Signed-off-by: Stephan Gerhold > > > --- > > > Changes since RFC: None. > > > --- > > > .../bindings/net/qcom,bam-dmux.yaml | 87 +++++++++++++++++++ > > > 1 file changed, 87 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/net/qcom,bam-dmux.yaml > > > > > > diff --git a/Documentation/devicetree/bindings/net/qcom,bam-dmux.yaml b/Documentation/devicetree/bindings/net/qcom,bam-dmux.yaml > > > new file mode 100644 > > > index 000000000000..33e125e70cb4 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/net/qcom,bam-dmux.yaml > > > @@ -0,0 +1,87 @@ > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/net/qcom,bam-dmux.yaml# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > + > > > +title: Qualcomm BAM Data Multiplexer > > > + > > > +maintainers: > > > + - Stephan Gerhold > > > + > > > +description: | > > > + The BAM Data Multiplexer provides access to the network data channels > > > + of modems integrated into many older Qualcomm SoCs, e.g. Qualcomm MSM8916 > > > + or MSM8974. It is built using a simple protocol layer on top of a DMA engine > > > + (Qualcomm BAM DMA) and bidirectional interrupts to coordinate power control. > > > + > > > +properties: > > > + compatible: > > > + const: qcom,bam-dmux > > > > Is this block the same on every SoC? It needs to be SoC specific. > > > > Hm, I think describing it as *SoC*-specific wouldn't be accurate: > This node does not describe any hardware block, it's more a "firmware > convention". The only hardware involved is the BAM DMA engine, which > already has SoC/IP-specific compatibles in its own device tree node. > > This means that if anything there should be "firmware version"-specific > compatibles, because one SoC might have different (typically signed) > firmware versions that provide slightly different functionality. > However, I have to admit that I'm not familiar enough with the different > firmware versions to come up with a reasonable naming schema for the > compatible. :/ > > In general, I cannot think of any difference between different versions > that would matter to a driver. The protocol is quite simple, and minor > firmware differences can be better handled through the control channel > that sets up the connection for the modem. > > Does that make sense? Okay. Please add some of the above details to the binding. Rob