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 3A018EB64D7 for ; Wed, 21 Jun 2023 23:02:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229681AbjFUXCV (ORCPT ); Wed, 21 Jun 2023 19:02:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229521AbjFUXCT (ORCPT ); Wed, 21 Jun 2023 19:02:19 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 777CE1981 for ; Wed, 21 Jun 2023 16:02:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1687388538; x=1718924538; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=C/tAdtPH8/FfpGCzsRCGmO+KPnY+oJzm0w5UzTCHRPU=; b=fEZQ6hsg6/UA+wlsnySKzs6z1mM/UxhINYZ0KnKNWyNelZ8wRE6b2N6h 1SHIY4q6/B1fjMX59/QkmoRS4kH18getNcgUVJcZRN3rmWhfyXth7rvID Kd6KmTOR5dgecjKndQuATERTxQfpjeb5piuqfMvEHa9bXJhlV/y8pI8Ou ACrr6ySKq9tgf1TgDp901zlYym/RW6fzzyMLYDqlcpJtekKzF2o4SxKl7 2nh+/mRxbYEUJF4OmO468hMAqspsiHiWtz7EOoBCUr7FtFV1MDWEwBi5i GStBj9MA31CWquni8Ow0xQJyImH0vnVE1zO6Nopd7ZmxSBgdHYXvrZA7b g==; X-IronPort-AV: E=McAfee;i="6600,9927,10748"; a="426288959" X-IronPort-AV: E=Sophos;i="6.00,261,1681196400"; d="scan'208";a="426288959" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Jun 2023 16:02:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10748"; a="708879767" X-IronPort-AV: E=Sophos;i="6.00,261,1681196400"; d="scan'208";a="708879767" Received: from patelni-mobl1.amr.corp.intel.com (HELO [10.78.16.163]) ([10.78.16.163]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Jun 2023 16:02:17 -0700 Message-ID: Date: Wed, 21 Jun 2023 16:02:16 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.11.2 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. I will make the adjustment. > >> 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 >>