From nobody Mon Feb 9 16:56:20 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of groups.io designates 66.175.222.12 as permitted sender) client-ip=66.175.222.12; envelope-from=bounce+27952+53537+1787277+3901457@groups.io; helo=web01.groups.io; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.12 as permitted sender) smtp.mailfrom=bounce+27952+53537+1787277+3901457@groups.io; dmarc=fail(p=none dis=none) header.from=redhat.com Received: from web01.groups.io (web01.groups.io [66.175.222.12]) by mx.zohomail.com with SMTPS id 1580334268529142.17697390344415; Wed, 29 Jan 2020 13:44:28 -0800 (PST) Return-Path: X-Received: by 127.0.0.2 with SMTP id C1LcYY1788612xKaaa0nqYNr; Wed, 29 Jan 2020 13:44:27 -0800 X-Received: from us-smtp-delivery-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.81]) by mx.groups.io with SMTP id smtpd.web09.594.1580334266926465901 for ; Wed, 29 Jan 2020 13:44:27 -0800 X-Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-225-W3t-7iZdMNaIZsk4p_A46Q-1; Wed, 29 Jan 2020 16:44:21 -0500 X-Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1E92F107ACC9; Wed, 29 Jan 2020 21:44:20 +0000 (UTC) X-Received: from lacos-laptop-7.usersys.redhat.com (ovpn-116-32.ams2.redhat.com [10.36.116.32]) by smtp.corp.redhat.com (Postfix) with ESMTP id 26BC95DA75; Wed, 29 Jan 2020 21:44:18 +0000 (UTC) From: "Laszlo Ersek" To: edk2-devel-groups-io Cc: Ard Biesheuvel , Jordan Justen Subject: [edk2-devel] [PATCH v2 03/11] OvmfPkg/IndustryStandard: add MCH_DEFAULT_SMBASE* register macros Date: Wed, 29 Jan 2020 22:44:04 +0100 Message-Id: <20200129214412.2361-4-lersek@redhat.com> In-Reply-To: <20200129214412.2361-1-lersek@redhat.com> References: <20200129214412.2361-1-lersek@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-MC-Unique: W3t-7iZdMNaIZsk4p_A46Q-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Precedence: Bulk List-Unsubscribe: Sender: devel@edk2.groups.io List-Id: Mailing-List: list devel@edk2.groups.io; contact devel+owner@edk2.groups.io Reply-To: devel@edk2.groups.io,lersek@redhat.com X-Gm-Message-State: bHMzG0uo5kjV4q5qiycSthK4x1787277AA= Content-Transfer-Encoding: quoted-printable DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=groups.io; q=dns/txt; s=20140610; t=1580334267; bh=SgF8+SoucRYkIqQ26Djb6a/DWxWCfrE5G0eOYGfaZeQ=; h=Cc:Content-Type:Date:From:Reply-To:Subject:To; b=okb1UN62AgGvyUbOafLyFjg6dZnd1ui6Za0vL3CfpWF6ZVq0av2dXmx+k0WcBk7KMWx 5Z+zsULyXIg5bl9ZPVN6Py29GmcVI+i6iKKBQfM7X30YSSVrJQjLMJXOahOuolGsl9jq2 MX/qO0D9a0YoG7XfqOELmZrPkwN+/cLFqaA= X-ZohoMail-DKIM: pass (identity @groups.io) Content-Type: text/plain; charset="utf-8" In Intel datasheet 316966-002 (the "q35 spec"), Table 5-1 "DRAM Controller Register Address Map (D0:F0)" leaves the byte register at config space offset 0x9C unused. On QEMU's Q35 board, for detecting the "SMRAM at default SMBASE" feature, firmware is expected to write MCH_DEFAULT_SMBASE_QUERY (0xFF) to offset MCH_DEFAULT_SMBASE_CTL (0x9C), and read back the register. If the value is MCH_DEFAULT_SMBASE_IN_RAM (0x01), then the feature is available, and the range mentioned below is open (accessible to code running outside of SMM). Then, once firmware writes MCH_DEFAULT_SMBASE_LCK (0x02) to the register, the MCH_DEFAULT_SMBASE_SIZE (128KB) range at 0x3_0000 (SMM_DEFAULT_SMBASE) gets closed and locked down, and the register becomes read-only. The area is reopened, and the register becomes read/write, at platform reset. Add the above-listed macros to "Q35MchIch9.h". (There are some other unused offsets in Table 5-1; for example we had scavenged 0x50 for implementing the extended TSEG feature. 0x9C is the first byte-wide register standing in isolation after 0x50.) Cc: Ard Biesheuvel Cc: Jordan Justen Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3D1512 Signed-off-by: Laszlo Ersek Reviewed-by: Jiewen Yao --- Notes: v2: - trim Cc list - pick up Jiewen's R-b OvmfPkg/Include/IndustryStandard/Q35MchIch9.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/OvmfPkg/Include/IndustryStandard/Q35MchIch9.h b/OvmfPkg/Includ= e/IndustryStandard/Q35MchIch9.h index 80379c223a1c..cb705fee92ca 100644 --- a/OvmfPkg/Include/IndustryStandard/Q35MchIch9.h +++ b/OvmfPkg/Include/IndustryStandard/Q35MchIch9.h @@ -49,6 +49,12 @@ #define MCH_PAM5 0x95 #define MCH_PAM6 0x96 =20 +#define MCH_DEFAULT_SMBASE_CTL 0x9C +#define MCH_DEFAULT_SMBASE_QUERY 0xFF +#define MCH_DEFAULT_SMBASE_IN_RAM 0x01 +#define MCH_DEFAULT_SMBASE_LCK 0x02 +#define MCH_DEFAULT_SMBASE_SIZE SIZE_128KB + #define MCH_SMRAM 0x9D #define MCH_SMRAM_D_LCK BIT4 #define MCH_SMRAM_G_SMRAME BIT3 --=20 2.19.1.3.g30247aa5d201 -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D- Groups.io Links: You receive all messages sent to this group. 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