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=-0.8 required=3.0 tests=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 52872C35242 for ; Fri, 24 Jan 2020 11:55:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 26B69206F0 for ; Fri, 24 Jan 2020 11:55:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387991AbgAXLzs (ORCPT ); Fri, 24 Jan 2020 06:55:48 -0500 Received: from mx2.suse.de ([195.135.220.15]:57622 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729567AbgAXLzs (ORCPT ); Fri, 24 Jan 2020 06:55:48 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id C0972ABED; Fri, 24 Jan 2020 11:55:46 +0000 (UTC) Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 In-Reply-To: Date: Fri, 24 Jan 2020 12:51:52 +0100 Cc: , "Catalin Marinas" , , , "Will Deacon" , Subject: Re: [PATCH for-next] arm64: defconfig: Set bcm2835-dma as built-in From: "Nicolas Saenz Julienne" To: "Peter Ujfalusi" , "Ulf Hansson" Message-Id: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Peter, On Fri Jan 24, 2020 at 1:31 PM, Peter Ujfalusi wrote: > Hi Nicolas, > > On 24/01/2020 13.17, Nicolas Saenz Julienne wrote: > > With the introduction of 738987a1d6f1 ("mmc: bcm2835: Use > > dma_request_chan() instead dma_request_slave_channel()") sdhost-bcm2835 > > now waits for its DMA channel to be available when defined in the > > device-tree (it would previously default to PIO). Albeit the right > > behaviour, the MMC host is needed for booting. So this makes sure the > > DMA channel shows up in time. > >=20 > > Fixes: 738987a1d6f1 ("mmc: bcm2835: Use dma_request_chan() instead dma_= request_slave_channel()") > > it is not a bug, it is a feature ;) Agree, I'm just afraid of your series being picked up by a stable release without this patch. But maybe it's not necessary? > Yes, if a driver have DMA binding and it is needed during boot then the > DMA driver also needs to be built in. > I believe it is desired to use DMA instead of PIO in any case for MMC > and in the past bcm2835 did not used DMA if DMA was module and the MMC > was built in. > > Sorry for the inconvenience this change has caused to bcm2835! Not at all :) > Reviewed-by: Peter Ujfalusi Thanks, Nicolas 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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,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 A40EBC2D0DB for ; Fri, 24 Jan 2020 11:55:54 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 76CBF206D5 for ; Fri, 24 Jan 2020 11:55:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="X6k2WWAb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 76CBF206D5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Message-Id:To:From: Subject:Date:In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:References: List-Owner; bh=8DVW+o2FOzhQ4Xdvn7wGnoEqsrasKRiT0VJ1tDRyLqM=; b=X6k2WWAbtGsIxG 5H81HOZhmFIz+owlpToIYufur86pQhDftCfvpfrwKWuv5uiQ/t4xWEWLODiVczot+xlsUZ6x+UBBU fY0Pyd53n0x59G5FBB6qy/fFjjCnhTKLfyGH0QrNJ4CSxBncrhPXet9QTW+0A6BbS4hXKi4O3V0GV pEpOCOBtM4jGT2Yv6drgsFNZUlR5Z8BPBboyAOovP8VAlCIMzVFtEXF1J7gAxUuK+XcbdM2HVL/r/ x38I0nt4T9eW5wslQgM4hq0pXbEiOiVABDyRnkTRvAQBv5csJiBLcQiMY9wAbbLDxhkLt9yeovzOx dyvrhfYZf/1A9zAA6DNQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iuxZ1-00025D-TA; Fri, 24 Jan 2020 11:55:51 +0000 Received: from mx2.suse.de ([195.135.220.15]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iuxYy-00024G-C8; Fri, 24 Jan 2020 11:55:49 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id C0972ABED; Fri, 24 Jan 2020 11:55:46 +0000 (UTC) In-Reply-To: Date: Fri, 24 Jan 2020 12:51:52 +0100 Subject: Re: [PATCH for-next] arm64: defconfig: Set bcm2835-dma as built-in From: "Nicolas Saenz Julienne" To: "Peter Ujfalusi" , "Ulf Hansson" Message-Id: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200124_035548_557826_E902C39A X-CRM114-Status: GOOD ( 16.95 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: f.fainelli@gmail.com, Catalin Marinas , linux-kernel@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, Will Deacon , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Peter, On Fri Jan 24, 2020 at 1:31 PM, Peter Ujfalusi wrote: > Hi Nicolas, > > On 24/01/2020 13.17, Nicolas Saenz Julienne wrote: > > With the introduction of 738987a1d6f1 ("mmc: bcm2835: Use > > dma_request_chan() instead dma_request_slave_channel()") sdhost-bcm2835 > > now waits for its DMA channel to be available when defined in the > > device-tree (it would previously default to PIO). Albeit the right > > behaviour, the MMC host is needed for booting. So this makes sure the > > DMA channel shows up in time. > > > > Fixes: 738987a1d6f1 ("mmc: bcm2835: Use dma_request_chan() instead dma_request_slave_channel()") > > it is not a bug, it is a feature ;) Agree, I'm just afraid of your series being picked up by a stable release without this patch. But maybe it's not necessary? > Yes, if a driver have DMA binding and it is needed during boot then the > DMA driver also needs to be built in. > I believe it is desired to use DMA instead of PIO in any case for MMC > and in the past bcm2835 did not used DMA if DMA was module and the MMC > was built in. > > Sorry for the inconvenience this change has caused to bcm2835! Not at all :) > Reviewed-by: Peter Ujfalusi Thanks, Nicolas _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel