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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 352BAC433FE for ; Fri, 11 Dec 2020 17:46:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 08D1022D06 for ; Fri, 11 Dec 2020 17:46:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389440AbgLKQoN (ORCPT ); Fri, 11 Dec 2020 11:44:13 -0500 Received: from pegase1.c-s.fr ([93.17.236.30]:54299 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389370AbgLKQnq (ORCPT ); Fri, 11 Dec 2020 11:43:46 -0500 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 4CsxRT3xzLzB09b7; Fri, 11 Dec 2020 17:43:01 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id C73GqEBCrzBF; Fri, 11 Dec 2020 17:43:01 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 4CsxRT2BQczB09Zs; Fri, 11 Dec 2020 17:43:01 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 4ECDF8B86D; Fri, 11 Dec 2020 17:43:02 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id GfDfkE2H2mL7; Fri, 11 Dec 2020 17:43:01 +0100 (CET) Received: from [192.168.4.90] (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id D11DF8B869; Fri, 11 Dec 2020 17:42:57 +0100 (CET) Subject: Re: [PATCH] net: ethernet: fs-enet: remove casting dma_alloc_coherent To: David Laight , Xu Wang , "pantelis.antoniou@gmail.com" , "davem@davemloft.net" , "kuba@kernel.org" , "linuxppc-dev@lists.ozlabs.org" Cc: "linux-kernel@vger.kernel.org" References: <20201211085212.85457-1-vulab@iscas.ac.cn> <34548188-67f4-d3ef-c2e3-871fc520e838@csgroup.eu> <6fc4b62ee7754d78b8f7b9c2275bc47e@AcuMS.aculab.com> From: Christophe Leroy Message-ID: <4a1c2852-781f-e125-afcb-69387660b6af@csgroup.eu> Date: Fri, 11 Dec 2020 17:42:56 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.5.1 MIME-Version: 1.0 In-Reply-To: <6fc4b62ee7754d78b8f7b9c2275bc47e@AcuMS.aculab.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: fr Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le 11/12/2020 à 17:07, David Laight a écrit : > From: Christophe Leroy >> Sent: 11 December 2020 15:22 >> >> Le 11/12/2020 à 09:52, Xu Wang a écrit : >>> Remove casting the values returned by dma_alloc_coherent. >> >> Can you explain more in the commit log ? >> >> As far as I can see, dma_alloc_coherent() doesn't return __iomem, and ring_base member is __iomem > > Which is probably wrong - that is the kernel address of kernel memory. > So it shouldn't have the __iomem marker. That's where the buffer descriptors are, the driver accesses to the content of the buffer descriptors using the IO accessors in_be16()/out_be16(). Is it not correct ? Christophe > > I wonder what else is wrong.... > > David > >> >> Christophe >> >>> >>> Signed-off-by: Xu Wang >>> --- >>> drivers/net/ethernet/freescale/fs_enet/mac-fec.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/net/ethernet/freescale/fs_enet/mac-fec.c >> b/drivers/net/ethernet/freescale/fs_enet/mac-fec.c >>> index 99fe2c210d0f..3ae345676e50 100644 >>> --- a/drivers/net/ethernet/freescale/fs_enet/mac-fec.c >>> +++ b/drivers/net/ethernet/freescale/fs_enet/mac-fec.c >>> @@ -131,7 +131,7 @@ static int allocate_bd(struct net_device *dev) >>> struct fs_enet_private *fep = netdev_priv(dev); >>> const struct fs_platform_info *fpi = fep->fpi; >>> >>> - fep->ring_base = (void __force __iomem *)dma_alloc_coherent(fep->dev, >>> + fep->ring_base = dma_alloc_coherent(fep->dev, >>> (fpi->tx_ring + fpi->rx_ring) * >>> sizeof(cbd_t), &fep->ring_mem_addr, >>> GFP_KERNEL); >>> > > - > Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK > Registration No: 1397386 (Wales) >