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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 ACC13C7618F for ; Mon, 15 Jul 2019 15:10:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82B6F2054F for ; Mon, 15 Jul 2019 15:10:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="lHtyRcsc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732103AbfGOPK1 (ORCPT ); Mon, 15 Jul 2019 11:10:27 -0400 Received: from pandora.armlinux.org.uk ([78.32.30.218]:43476 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387774AbfGOPK1 (ORCPT ); Mon, 15 Jul 2019 11:10:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=7d9E/+uS/LbEKMv/pk7fdGoaJqxaCi45qzlBCe6X+y4=; b=lHtyRcscbEO/YUttpfQ+8XJXr SgvcFo5dej0fLuJGCyAUQXfY8b7qYZk7MA6Ry/NOsaCVP3Seq9QZlTyxUxFNY2xCJisicRvGtqVrB i1H/ucs5/MDbD49uoiiQZJ/nYSi4yQ37Kq1Pp5EQLu9WpbxAsJ1FfywnHKzJQ+Qg5kWZay77jQM+l kwTdjJRNzEzwarQKzBLxMa/1Xocfi88NjsQEQXFGnvis2ZfUkrgKMB40yIxya+AmzwX2WgTo0S/4W bSRDMckeCH7L3Y7eAR0R0y/WKu90pE3bnZj935+9oie6ejVn80D1rLQOTUFamgZsdHw30JnP7sqag wKfX3hLwg==; Received: from shell.armlinux.org.uk ([2001:4d48:ad52:3201:5054:ff:fe00:4ec]:59426) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1hn2cO-0005fa-A5; Mon, 15 Jul 2019 16:10:20 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.89) (envelope-from ) id 1hn2cK-0008SY-Ik; Mon, 15 Jul 2019 16:10:16 +0100 Date: Mon, 15 Jul 2019 16:10:16 +0100 From: Russell King - ARM Linux admin To: Thomas Petazzoni Cc: Grzegorz Jaszczyk , lorenzo.pieralisi@arm.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, mw@semihalf.com Subject: Re: [PATCH] PCI: aardvark: fix big endian support Message-ID: <20190715151016.6amymuikizmmmsph@shell.armlinux.org.uk> References: <1563200122-8323-1-git-send-email-jaz@semihalf.com> <20190715170840.326acd73@windsurf> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190715170840.326acd73@windsurf> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, Jul 15, 2019 at 05:08:40PM +0200, Thomas Petazzoni wrote: > Hello Grzegorz, > > Thanks for this work. I indeed never tested this code on BE platforms, > and it is very possible that I overlooked endianness issues, so thanks > for having a look at this and proposing some patches. See some > questions/comments below. > > On Mon, 15 Jul 2019 16:15:22 +0200 > Grzegorz Jaszczyk wrote: > > > Initialise every not-byte wide fields of emulated pci bridge config > > space with proper cpu_to_le* macro. This is required since the structure > > describing config space of emulated bridge assumes little-endian > > convention. > > > > Signed-off-by: Grzegorz Jaszczyk > > --- > > drivers/pci/controller/pci-aardvark.c | 10 ++++++---- > > 1 file changed, 6 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c > > index 134e030..06a12749 100644 > > --- a/drivers/pci/controller/pci-aardvark.c > > +++ b/drivers/pci/controller/pci-aardvark.c > > @@ -479,8 +479,10 @@ static void advk_sw_pci_bridge_init(struct advk_pcie *pcie) > > { > > struct pci_bridge_emul *bridge = &pcie->bridge; > > > > - bridge->conf.vendor = advk_readl(pcie, PCIE_CORE_DEV_ID_REG) & 0xffff; > > - bridge->conf.device = advk_readl(pcie, PCIE_CORE_DEV_ID_REG) >> 16; > > + bridge->conf.vendor = > > + cpu_to_le16(advk_readl(pcie, PCIE_CORE_DEV_ID_REG) & 0xffff); > > + bridge->conf.device = > > + cpu_to_le16(advk_readl(pcie, PCIE_CORE_DEV_ID_REG) >> 16); > > bridge->conf.class_revision = > > advk_readl(pcie, PCIE_CORE_DEV_REV_REG) & 0xff; > > So conf.vendor and conf.device and stored as little-endian in the > emulated config address space, but conf.class_revision is stored in the > CPU endianness ? > > > > > @@ -489,8 +491,8 @@ static void advk_sw_pci_bridge_init(struct advk_pcie *pcie) > > bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32; > > > > > /* Support 64 bits memory pref */ > > - bridge->conf.pref_mem_base = PCI_PREF_RANGE_TYPE_64; > > - bridge->conf.pref_mem_limit = PCI_PREF_RANGE_TYPE_64; > > + bridge->conf.pref_mem_base = cpu_to_le16(PCI_PREF_RANGE_TYPE_64); > > + bridge->conf.pref_mem_limit = cpu_to_le16(PCI_PREF_RANGE_TYPE_64); > > Same here: why are conf.pref_mem_{base,limit} converted to LE, but not > conf.iolimit ? > > Also, the advk_pci_bridge_emul_pcie_conf_read() and > advk_pci_bridge_emul_pcie_conf_write() return values that are in the > CPU endianness. > > Am I missing something ? Getting the types correct and then using Sparse to validate the code will help to identify issues exactly like this. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up