From nobody Sun Feb 8 23:58:05 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) client-ip=66.175.222.108; envelope-from=bounce+27952+77679+1787277+3901457@groups.io; helo=mail02.groups.io; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce+27952+77679+1787277+3901457@groups.io; dmarc=fail(p=none dis=none) header.from=intel.com ARC-Seal: i=1; a=rsa-sha256; t=1626052817; cv=none; d=zohomail.com; s=zohoarc; b=jrbtBkQFoFcYOpgLlmAYOGY2nr1+mq0fMNuDirmp0yDiJLjWVOrcLGk+kKlErLnnllZ4QPHG1odO+fsfRJivZMsI59yTZbsBk2bNxF7OBosyMdslrgs8K7c2AXAIA9LIMJDWI+0GsLJgWpUD6I/tfW6AfnhzqiAmykm0EctdcHg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1626052817; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Reply-To:References:Sender:Subject:To; bh=J9bNW1i5IvMDdA5m59qDF+tyUg3PNSOsfXo+seR2m4Q=; b=cYdmvuNTy2gK8I88Ib0HZmZmXfeXScCldQyQSpRWTecFHWK+yDtS4hBAZufGebYJvxh25bbofwz5c7ezQabymUi4Adh5hxy5DgaUhLxhJA/cCNKC1U2wUMYneG3JyOoqnLvzE1aLjZ9kXzewGHoi2o7dllm5aUSCWWCRIFGrdLw= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce+27952+77679+1787277+3901457@groups.io; dmarc=fail header.from= (p=none dis=none) Received: from mail02.groups.io (mail02.groups.io [66.175.222.108]) by mx.zohomail.com with SMTPS id 1626052817511777.8168598273026; Sun, 11 Jul 2021 18:20:17 -0700 (PDT) Return-Path: X-Received: by 127.0.0.2 with SMTP id ZJ4xYY1788612xYvGrdevM5n; Sun, 11 Jul 2021 18:20:17 -0700 X-Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by mx.groups.io with SMTP id smtpd.web12.5424.1626052808517988836 for ; Sun, 11 Jul 2021 18:20:16 -0700 X-IronPort-AV: E=McAfee;i="6200,9189,10042"; a="209726408" X-IronPort-AV: E=Sophos;i="5.84,232,1620716400"; d="scan'208";a="209726408" X-Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jul 2021 18:20:16 -0700 X-IronPort-AV: E=Sophos;i="5.84,232,1620716400"; d="scan'208";a="459018165" X-Received: from mxu9-mobl1.ccr.corp.intel.com ([10.238.4.4]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jul 2021 18:20:14 -0700 From: "Min Xu" To: devel@edk2.groups.io Cc: Min Xu , Eric Dong , Jiewen Yao , Ray Ni , Laszlo Ersek Subject: [edk2-devel] [PATCH 4/6] UefiCpuPkg/ResetVector: Add ReloadFlat32 in UefiCpuPkg Date: Mon, 12 Jul 2021 09:19:40 +0800 Message-Id: <4a08dc5d3adbc83f8048db44a6937138048d4435.1626050798.git.min.m.xu@intel.com> In-Reply-To: References: MIME-Version: 1.0 Precedence: Bulk List-Unsubscribe: List-Subscribe: List-Help: 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,min.m.xu@intel.com X-Gm-Message-State: HXyt6ik1shj7IrV0rQfL6fOdx1787277AA= Content-Transfer-Encoding: quoted-printable DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=groups.io; q=dns/txt; s=20140610; t=1626052817; bh=W9JEOQioQ+mN4gXKsZkc3IK2yURsnwcJrZqG04MAUrw=; h=Cc:Date:From:Reply-To:Subject:To; b=FSoaeftznm6LsiBWV5sE4J3zvg/NEIdGv2v+AS4bAWolR3lLz59ibhvq6SPrpWQGElE k1qmwtFA9728rxc6NJYdFNV1Trr5jxuj7tolT2QqNqOGNnEmVirvlIjUeZTVNZ6FNYoqX 31Ijnw1VhsnEJke35S3hIjPErfOWmdHCNZ4= X-ZohoMail-DKIM: pass (identity @groups.io) X-ZM-MESSAGEID: 1626052818332100006 Content-Type: text/plain; charset="utf-8" RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3D3429 Load the GDT and set the default CR0, then jump to Flat 32 protected mode. Cc: Eric Dong Cc: Jiewen Yao Cc: Ray Ni Cc: Laszlo Ersek Signed-off-by: Min Xu --- .../ResetVector/Vtf0/Ia32/ReloadFlat32.asm | 43 +++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 UefiCpuPkg/ResetVector/Vtf0/Ia32/ReloadFlat32.asm diff --git a/UefiCpuPkg/ResetVector/Vtf0/Ia32/ReloadFlat32.asm b/UefiCpuPkg= /ResetVector/Vtf0/Ia32/ReloadFlat32.asm new file mode 100644 index 000000000000..e8a4c47762df --- /dev/null +++ b/UefiCpuPkg/ResetVector/Vtf0/Ia32/ReloadFlat32.asm @@ -0,0 +1,43 @@ +;-------------------------------------------------------------------------= ----- +; @file +; Load the GDT and set the CR0, then jump to Flat 32 protected mode. +; +; Copyright (c) 2021, Intel Corporation. All rights reserved.
+; SPDX-License-Identifier: BSD-2-Clause-Patent +; +;-------------------------------------------------------------------------= ----- + +%define SEC_DEFAULT_CR0 0x00000023 +%define SEC_DEFAULT_CR4 0x640 + +BITS 32 + +; +; Modified: EAX, EBX, CR0, CR4, DS, ES, FS, GS, SS +; +ReloadFlat32: + + cli + mov ebx, ADDR_OF(gdtr) + lgdt [ebx] + + mov eax, SEC_DEFAULT_CR0 + mov cr0, eax + + jmp LINEAR_CODE_SEL:dword ADDR_OF(jumpToFlat32BitAndLandHere) +BITS 32 +jumpToFlat32BitAndLandHere: + + mov eax, SEC_DEFAULT_CR4 + mov cr4, eax + + debugShowPostCode POSTCODE_32BIT_MODE + + mov ax, LINEAR_SEL + mov ds, ax + mov es, ax + mov fs, ax + mov gs, ax + mov ss, ax + + OneTimeCallRet ReloadFlat32 --=20 2.29.2.windows.2 -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#77679): https://edk2.groups.io/g/devel/message/77679 Mute This Topic: https://groups.io/mt/84144141/1787277 Group Owner: devel+owner@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [importer@patchew.org] -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-