From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from EUR01-VE1-obe.outbound.protection.outlook.com (mail-ve1eur01on061b.outbound.protection.outlook.com [IPv6:2a01:111:f400:fe1f::61b]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 6F30F81EE0 for ; Tue, 15 Nov 2016 11:27:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector1-arm-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version; bh=zPr2kJK/rPeUuMR1vay3uhkwG0O5MGvW01ZUELo3+uw=; b=hq9zk39ay7+VbbW7r72du1ZHrGz+j6r0qOTB8llT6q6RodMVNSr3ks+/+75Q+EglNyz2RatvxelLw60HE9dlxUOuN2x8OPmQamCaXOsPG4jBOXTV4SbL80Vv3Qr8A+wn7hHeYR8VwurbU/WqW832HJ+vPjQp1f7iFZK70LUvats= Received: from AM5PR0801MB1762.eurprd08.prod.outlook.com (10.169.247.16) by AM5PR0801MB2084.eurprd08.prod.outlook.com (10.168.158.150) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P384) id 15.1.721.10; Tue, 15 Nov 2016 19:27:02 +0000 Received: from AM5PR0801MB1762.eurprd08.prod.outlook.com ([10.169.247.16]) by AM5PR0801MB1762.eurprd08.prod.outlook.com ([10.169.247.16]) with mapi id 15.01.0721.015; Tue, 15 Nov 2016 19:27:02 +0000 From: Evan Lloyd To: Laszlo Ersek , "edk2-devel (edk2-devel@lists.01.org)" , "ard.biesheuvel@linaro.org" , Star Zeng , Jordan Justen , Feng Tian CC: Lorenzo Pieralisi , Leif Lindholm Thread-Topic: [edk2] Support for ACPI 1.0 Thread-Index: AdI/NtZFLdUg5347R2CRdh44JGJvKAAKlNeAAABEsBA= Date: Tue, 15 Nov 2016 19:27:02 +0000 Message-ID: References: <5863f527-d6b9-55e2-9560-9d138ac9ce1a@redhat.com> In-Reply-To: <5863f527-d6b9-55e2-9560-9d138ac9ce1a@redhat.com> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: spf=none (sender IP is ) smtp.mailfrom=Evan.Lloyd@arm.com; x-originating-ip: [217.140.96.140] x-microsoft-exchange-diagnostics: 1; AM5PR0801MB2084; 7:bN7oskm93rwTkYpXOjxI/i+3/nuRoODEhifHhFQfa1Vaa3YJ9CgpTJPup5Ry35TkXvjnJbrJy1mv0g7YcRc+8ECzW/nD+xcMtmVHvcrzUlUFksyRgtUYEGe1s/ytthfIgLw+efE7jURKBfW9ryDTKx3tnY2qYrSu6e+Lm+CrbyIVzjjQwXco2v6WRIj/ITG0vzRjhZ1pK8rJjxVpsMIV+vS43YFzRWZV5HIij6KrocT4V3yolBaTZEuaGuf3gPZmbHOFTvhgnKKCl2FwJ06X2Lyrmphy6WiF1qtjWEcV1VDX4gKGwTwQ0i8jDH2v5mx0jvh10YXh3naXBz4Djo/dfiSBEvs7Ftick3AgJSECV/E= x-ms-office365-filtering-correlation-id: 548e3a20-bf28-41ea-8b18-08d40d8d6062 x-microsoft-antispam: UriScan:; BCL:0; PCL:0; RULEID:(22001); SRVR:AM5PR0801MB2084; x-ld-processed: f34e5979-57d9-4aaa-ad4d-b122a662184d,ExtAddr x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(162533806227266); x-exchange-antispam-report-cfa-test: BCL:0; PCL:0; RULEID:(6060326)(601004)(2401047)(5005006)(8121501046)(3002001)(10201501046)(6055026)(6061324); SRVR:AM5PR0801MB2084; BCL:0; PCL:0; RULEID:; SRVR:AM5PR0801MB2084; x-forefront-prvs: 012792EC17 x-forefront-antispam-report: SFV:NSPM; SFS:(10009020)(6009001)(7916002)(24454002)(199003)(13464003)(40434004)(189002)(3846002)(102836003)(6116002)(101416001)(7696004)(122556002)(8676002)(2906002)(68736007)(87936001)(86362001)(2900100001)(5660300001)(77096005)(50986999)(54356999)(5001770100001)(305945005)(76176999)(189998001)(9686002)(229853002)(105586002)(66066001)(76576001)(74316002)(3280700002)(3660700001)(97736004)(4326007)(106356001)(2950100002)(2501003)(345774005)(5890100001)(92566002)(7736002)(8936002)(7846002)(81156014)(81166006)(33656002)(44824005); DIR:OUT; SFP:1101; SCL:1; SRVR:AM5PR0801MB2084; H:AM5PR0801MB1762.eurprd08.prod.outlook.com; FPR:; SPF:None; PTR:InfoNoRecords; A:1; MX:1; LANG:en; received-spf: None (protection.outlook.com: arm.com does not designate permitted sender hosts) spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM MIME-Version: 1.0 X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-originalarrivaltime: 15 Nov 2016 19:27:02.3772 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM5PR0801MB2084 Subject: Re: Support for ACPI 1.0 X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Nov 2016 19:27:02 -0000 Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Hi Laszlo. Thank you for the response. Comments inline below. >-----Original Message----- >From: Laszlo Ersek [mailto:lersek@redhat.com] >Sent: 15 November 2016 16:56 >To: Evan Lloyd; edk2-devel (edk2-devel@lists.01.org); >ard.biesheuvel@linaro.org; Star Zeng; Jordan Justen; Feng Tian >Cc: Lorenzo Pieralisi; Leif Lindholm >Subject: Re: [edk2] Support for ACPI 1.0 > >On 11/15/16 14:08, Evan Lloyd wrote: >> There is some wonderfully convoluted code in >MdeModulePkg/Universal/Acpi/AcpiTableDxe/AcpiTableProtocol.c >> A major cause of the complexity arises from the special cases related to >support for "EFI_ACPI_TABLE_VERSION_1_0B" or not >("ACPI_TABLE_VERSION_GTE_2_0"). >> >> We are seeing problems (SCT fails) related to this with the current code= , >and have been looking at a fix. >> >> However, it seems reasonable to question the requirement to support >ACPI 1.0 nowadays. >> Is there any need to retain support for such obsolete table versions? >> Should there be, could it at least be split out into a distinct build op= tion? > >It seems that this can be controlled through PcdAcpiExposedTableVersions - >- is that insufficient for your purpose? From The USE of the code can indeed be controlled with the Pcd. However my point is that to accommodate the idiosyncrasies of "ACPI_1_0B", = the code is complex and obscure. It also has bugs, largely because of that complexity. Were ACPI 1.0 support removed, it would become far simpler, more maintainab= le, and easier to debug. All the optional code for VERSION_1_0B or GTE_2_0 would become redundant, a= nd the updates we need to make would be simplified. For ARM, we only really care about ACPI 5.0 or later. I do not know what the support requirements might be for other platforms, b= ut ACPI 2.0 came out in 2000, so it seems reasonable to encourage people in= to this century, if not this decade. >"MdeModulePkg/MdeModulePkg.dec": > > ## Indicates which ACPI versions are targeted by the ACPI tables exposed >to the OS > # These values are aligned with the definitions in >MdePkg/Include/Protocol/AcpiSystemDescriptionTable.h > # BIT 1 - EFI_ACPI_TABLE_VERSION_1_0B.
> # BIT 2 - EFI_ACPI_TABLE_VERSION_2_0.
> # BIT 3 - EFI_ACPI_TABLE_VERSION_3_0.
> # BIT 4 - EFI_ACPI_TABLE_VERSION_4_0.
> # BIT 5 - EFI_ACPI_TABLE_VERSION_5_0.
> # @Prompt Exposed ACPI table versions. > Wot, no ACPI 6? (That is one issue we have found, especially with the GTE_= 2_0 macro.) >gEfiMdeModulePkgTokenSpaceGuid.PcdAcpiExposedTableVersions|0x3E| >UINT32|0x0001004c > >See commit e0692789058ee for example. > >Thanks! >Laszlo > >> >> Regards, >> Evan ... >> _______________________________________________ >> edk2-devel mailing list >> edk2-devel@lists.01.org >> https://lists.01.org/mailman/listinfo/edk2-devel >> IMPORTANT NOTICE: The contents of this email and any attachments are confid= ential and may also be privileged. If you are not the intended recipient, p= lease notify the sender immediately and do not disclose the contents to any= other person, use it for any purpose, or store or copy the information in = any medium. Thank you.