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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 4DDE4C433DF for ; Tue, 30 Jun 2020 11:32:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26E3820720 for ; Tue, 30 Jun 2020 11:32:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="gSl0z0zs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731395AbgF3Lct (ORCPT ); Tue, 30 Jun 2020 07:32:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54558 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726875AbgF3Lcs (ORCPT ); Tue, 30 Jun 2020 07:32:48 -0400 Received: from mail-il1-x143.google.com (mail-il1-x143.google.com [IPv6:2607:f8b0:4864:20::143]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A8CFC061755 for ; Tue, 30 Jun 2020 04:32:48 -0700 (PDT) Received: by mail-il1-x143.google.com with SMTP id t27so12398721ill.9 for ; Tue, 30 Jun 2020 04:32:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=LFNwIQlNioguafFY37IupRqLbXLAuXF9749fjHUWD6Y=; b=gSl0z0zsFnIBoY3OckvK4tvohfguwfPws/ENYsCnGk69ebLkaMHHI70JtDAvS5aM2G I5qkbw/q5+3OtRtG3HkAyYbRagCndeqvAHjvRxK8l3cbjX0ijkCyUEq0VR9wx8BuctuO AoVSRS/hJNC2A2uJrbpl+mn04PSBPuuQtb0LV+SL5nO7z6gc3OLjS1i3QTd2OIGH8U3s dCgqoEo4L+EvxaTrJxRJZAVtk/ZikzY1KisFViOMr4zsFIrZQWrpBAA965Y72TK9lcwk p9jBThf5nOF7lDDfgJXKJKtHwaUN9vfY8gi7l7imMRxnc3lQd4UOdUvdA/eZvUOVGp24 RDCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=LFNwIQlNioguafFY37IupRqLbXLAuXF9749fjHUWD6Y=; b=Bqexfy3GvXhqcotSRMpBAswjHnZIGhHWU3mLd9FsEwjzuxap7P1BDQgzgUBkWQucDJ fhZPWn/dHEeY4p1ugUiENmO6TeM87CmfBuG+Qy+71SdjpyeHKut2ACd690KfCNZsoUZu HDK8ID2+BfIYJBDCIrF3Py+ZW5JoFbAhIizS3Z3+Bzi3yFPCrUlhLBrtUW/TmRX+w2Rv 4EU2M7d8NsTPAgyAq87HCY0XoSMkszYDX3YfUJaeN2HE7k2NRz/ieCGfIxh8/u9hYblZ UtbMxKUkIulloBJt5A7+E2lgKHyBlrb91VPurnldUzUaj3Rf7QEYgBbzsxYvYO8ALAiT W3hA== X-Gm-Message-State: AOAM533ePOxwV6ejOL4q5UKK6IlrNiP9yF8H5zQ5LFBiL6txpbY0WVh9 dFQMcozLI8yVyJ8GVVstad2qVg== X-Google-Smtp-Source: ABdhPJzkusHBr3wMRg2ogpxb5Zvn7cGwdVZSB2LGMkofw+oZSsKxckSuJh5mnTyHUZwhalVbUzK04w== X-Received: by 2002:a92:410d:: with SMTP id o13mr2041308ila.298.1593516767773; Tue, 30 Jun 2020 04:32:47 -0700 (PDT) Received: from ziepe.ca ([206.223.160.26]) by smtp.gmail.com with ESMTPSA id x16sm1338207iob.35.2020.06.30.04.32.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 30 Jun 2020 04:32:46 -0700 (PDT) Received: from jgg by mlx with local (Exim 4.93) (envelope-from ) id 1jqEVJ-001XOb-QU; Tue, 30 Jun 2020 08:32:45 -0300 Date: Tue, 30 Jun 2020 08:32:45 -0300 From: Jason Gunthorpe To: Mark Brown Cc: Greg KH , Takashi Iwai , Pierre-Louis Bossart , Ranjani Sridharan , Jeff Kirsher , davem@davemloft.net, netdev@vger.kernel.org, linux-rdma@vger.kernel.org, nhorman@redhat.com, sassmann@redhat.com, Fred Oh , lee.jones@linaro.org Subject: Re: [net-next v4 10/12] ASoC: SOF: Introduce descriptors for SOF client Message-ID: <20200630113245.GG25301@ziepe.ca> References: <7abfbda8-2b4b-5301-6a86-1696d4898525@linux.intel.com> <20200523062351.GD3156699@kroah.com> <57185aae-e1c9-4380-7801-234a13deebae@linux.intel.com> <20200524063519.GB1369260@kroah.com> <20200527071733.GB52617@kroah.com> <20200629203317.GM5499@sirena.org.uk> <20200629225959.GF25301@ziepe.ca> <20200630103141.GA5272@sirena.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200630103141.GA5272@sirena.org.uk> Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Tue, Jun 30, 2020 at 11:31:41AM +0100, Mark Brown wrote: > On Mon, Jun 29, 2020 at 07:59:59PM -0300, Jason Gunthorpe wrote: > > On Mon, Jun 29, 2020 at 09:33:17PM +0100, Mark Brown wrote: > > > On Wed, May 27, 2020 at 09:17:33AM +0200, Greg KH wrote: > > > > > Ok, that's good to hear. But platform devices should never be showing > > > > up as a child of a PCI device. In the "near future" when we get the > > > > virtual bus code merged, we can convert any existing users like this to > > > > the new code. > > > > What are we supposed to do with things like PCI attached FPGAs and ASICs > > > in that case? They can have host visible devices with physical > > > resources like MMIO ranges and interrupts without those being split up > > > neatly as PCI subfunctions - the original use case for MFD was such > > > ASICs, there's a few PCI drivers in there now. > > > Greg has been pretty clear that MFD shouldn't have been used on top of > > PCI drivers. > > The proposed bus lacks resource handling, an equivalent of > platform_get_resource() and friends for example, which would be needed > for use with physical devices. Both that and the name suggest that it's > for virtual devices. Resource handling is only useful if the HW has a hard distinction between it's functional blocks. This scheme is intended for devices where that doesn't exist. The driver that attaches to the PCI device and creates the virtual devices is supposed to provide SW abstractions for the other drivers to sit on. I'm not sure why we are calling it virtual bus. > The reason the MFDs use platform devices is that they end up having to > have all the features of platform devices - originally people were > making virtual buses for them but the code duplication is real so > everyone (including Greg) decided to just use what was there already. Maybe Greg will explain why he didn't like the earlier version of that stuff that used MFD Jason