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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9C1D8EB64DA for ; Wed, 5 Jul 2023 17:39:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231577AbjGERjy (ORCPT ); Wed, 5 Jul 2023 13:39:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55432 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231269AbjGERjy (ORCPT ); Wed, 5 Jul 2023 13:39:54 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 41CEBDD for ; Wed, 5 Jul 2023 10:39:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1688578793; x=1720114793; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=Ac8Lx1yIas1EDP+xKycqKhHsPysWIxSR7v8TrywXDkg=; b=Y7pbi6cQHt6L0RkOz+62q7Mx+CJP9UzTlGOkSBSYbglR2hElYh5B8CR3 /zLgvX2iituJDfC2SLF1Vd3GMJI7JL9ce/CGHbDPLaNSLEV6qscuympHI pIroTETCd00+/2E/Dqxfy3RAPTOgd7LitcG2i2Iqb4Pl0q7S7lshp18Hz oocNrA6AYlbfb9snIRQhkbX67XUbxuoF/Di7ZOPXIlnoWJejC2eyywyeT VW0NltA0rh9t3X/G1my1QWrtAK8WbSztUDMC/BslLMkoPE5VTKd9YVxMV wjEzuhybxPKzCmh+UtAAz/rlOyZTGf5uMcBayYxDhRrWTlpkxebJ2qgRf w==; X-IronPort-AV: E=McAfee;i="6600,9927,10762"; a="449768359" X-IronPort-AV: E=Sophos;i="6.01,183,1684825200"; d="scan'208";a="449768359" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jul 2023 10:39:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10762"; a="1049794834" X-IronPort-AV: E=Sophos;i="6.01,183,1684825200"; d="scan'208";a="1049794834" Received: from patelni-mobl1.amr.corp.intel.com (HELO [10.78.16.132]) ([10.78.16.132]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jul 2023 10:39:52 -0700 Message-ID: Date: Wed, 5 Jul 2023 10:39:52 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.12.0 Subject: Re: [PATCH] PCI: vmd: Fix domain reset operation Content-Language: en-US To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org References: <20230620180745.GA52323@bhelgaas> From: "Patel, Nirmal" In-Reply-To: <20230620180745.GA52323@bhelgaas> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On 6/20/2023 11:07 AM, Bjorn Helgaas wrote: > On Tue, May 30, 2023 at 02:47:06PM -0700, Nirmal Patel wrote: >> During domain reset process we are accidentally enabling >> the prefetchable memory by writing 0x0 to Prefetchable Memory >> Base and Prefetchable Memory Limit registers. As a result certain >> platforms failed to boot up. >> >> Here is the quote from section 7.5.1.3.9 of PCI Express Base 6.0 spec: >> >> The Prefetchable Memory Limit register must be programmed to a smaller >> value than the Prefetchable Memory Base register if there is no >> prefetchable memory on the secondary side of the bridge. >> >> When clearing Prefetchable Memory Base, Prefetchable Memory >> Limit and Prefetchable Base Upper 32 bits, the prefetchable >> memory range becomes 0x0-0x575000fffff. As a result the >> prefetchable memory is enabled accidentally. >> >> Implementing correct operation by writing a value to Prefetchable >> Base Memory larger than the value of Prefetchable Memory Limit. > Oh, I forgot: better to use imperative mood here instead of present > participle ("-ing" form), e.g., "Write ... so that ..." > > This should probably use the same form as pci_disable_bridge_window(), > since I think it's doing the same thing. will do that. Thanks. > >> Signed-off-by: Nirmal Patel >> --- >> drivers/pci/controller/vmd.c | 14 ++++++++++++-- >> 1 file changed, 12 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c >> index 769eedeb8802..f3eb740e3028 100644 >> --- a/drivers/pci/controller/vmd.c >> +++ b/drivers/pci/controller/vmd.c >> @@ -526,8 +526,18 @@ static void vmd_domain_reset(struct vmd_dev *vmd) >> PCI_CLASS_BRIDGE_PCI)) >> continue; >> >> - memset_io(base + PCI_IO_BASE, 0, >> - PCI_ROM_ADDRESS1 - PCI_IO_BASE); >> + writel(0, base + PCI_IO_BASE); >> + writew(0xFFF0, base + PCI_MEMORY_BASE); >> + writew(0, base + PCI_MEMORY_LIMIT); >> + >> + writew(0xFFF1, base + PCI_PREF_MEMORY_BASE); >> + writew(0, base + PCI_PREF_MEMORY_LIMIT); >> + >> + writel(0xFFFFFFFF, base + PCI_PREF_BASE_UPPER32); >> + writel(0, base + PCI_PREF_LIMIT_UPPER32); >> + >> + writel(0, base + PCI_IO_BASE_UPPER16); >> + writeb(0, base + PCI_CAPABILITY_LIST); >> } >> } >> } >> -- >> 2.27.0 >>