From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 18F2C803BD for ; Mon, 20 Mar 2017 02:17:41 -0700 (PDT) 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 mx1.redhat.com (Postfix) with ESMTPS id 8698680516; Mon, 20 Mar 2017 09:17:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 8698680516 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=lersek@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 8698680516 Received: from lacos-laptop-7.usersys.redhat.com (ovpn-116-55.phx2.redhat.com [10.3.116.55]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5CFA25DD62; Mon, 20 Mar 2017 09:17:40 +0000 (UTC) To: "Zeng, Star" , edk2-devel-01 References: <20170317204731.31488-1-lersek@redhat.com> <20170317204731.31488-6-lersek@redhat.com> <0C09AFA07DD0434D9E2A0C6AEB0483103B835B4B@shsmsx102.ccr.corp.intel.com> Cc: Leif Lindholm , Ard Biesheuvel From: Laszlo Ersek Message-ID: Date: Mon, 20 Mar 2017 10:17:38 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <0C09AFA07DD0434D9E2A0C6AEB0483103B835B4B@shsmsx102.ccr.corp.intel.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 20 Mar 2017 09:17:41 +0000 (UTC) Subject: Re: [PATCH v2 05/12] ArmPkg: introduce EDKII Platform Has ACPI Protocol, and plug-in library X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 20 Mar 2017 09:17:41 -0000 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit On 03/20/17 03:23, Zeng, Star wrote: > Laszlo, > > Could the implementation have multiple instances of > PlatformHasAcpiLib to return unsuccessfully in the constructor when > EFI_ACPI_TABLE_PROTOCOL is not needed? And then eliminate > PlatformHasAcpiDtDxe, gEdkiiPlatformHasAcpiProtocolGuid and > gEdkiiPlatformHasDeviceTreeProtocolGuid? If a library constructor fails, then the client module does not see an explicit error (or automatic unloading); instead, an assertion failure is triggered in auto-generated code. For example, in the "Build/ArmVirtQemu-AARCH64/DEBUG_GCC5/AARCH64/MdeModulePkg/Universal/Acpi/AcpiTableDxe/AcpiTableDxe/DEBUG/AutoGen.c" file, with this series applied, we find: > VOID > EFIAPI > ProcessLibraryConstructorList ( > IN EFI_HANDLE ImageHandle, > IN EFI_SYSTEM_TABLE *SystemTable > ) > { > EFI_STATUS Status; > > Status = HobLibConstructor (ImageHandle, SystemTable); > ASSERT_EFI_ERROR (Status); > > Status = FdtPL011SerialPortLibInitialize (); > ASSERT_EFI_ERROR (Status); > > Status = BaseDebugLibSerialPortConstructor (); > ASSERT_EFI_ERROR (Status); > > Status = UefiBootServicesTableLibConstructor (ImageHandle, SystemTable); > ASSERT_EFI_ERROR (Status); > > Status = UefiRuntimeServicesTableLibConstructor (ImageHandle, SystemTable); > ASSERT_EFI_ERROR (Status); > > Status = UefiLibConstructor (ImageHandle, SystemTable); > ASSERT_EFI_ERROR (Status); > > Status = PlatformHasAcpiInitialize (); <--------------- constructor of PlatformHasAcpiLib plug-in lib > ASSERT_EFI_ERROR (Status); > > } What we could do instead would be a new library class, with an explicit initialization function. However, for that to work, AcpiTableDxe would have to be extended with a new library class dependency and a call to the init function. Additionally, out-of-tree platform DSC files would have to resolve this library class to the default instance. Introducing a boolean dynamic PCD for the same would be much simpler then; the DEC default would cover out-of-tree platform DSCs without any change in behavior. In summary, there are two alternatives in my opinion: (1) If we prefer not to modify MdeModulePkg: stick with this series. The only update I'd see justified would be to move gEdkiiPlatformHasDeviceTreeProtocolGuid to EmbeddedPkg as Leif requested. (2) If we are willing to modify MdeModulePkg for this problem: introduce a new dynamic PCD such as "PcdAcpiTableEnable", and make AcpiTableDxe exit early if the PCD is FALSE. Thanks, Laszlo > > Thanks, > Star > -----Original Message----- > From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of Laszlo Ersek > Sent: Saturday, March 18, 2017 4:47 AM > To: edk2-devel-01 > Cc: Leif Lindholm ; Ard Biesheuvel > Subject: [edk2] [PATCH v2 05/12] ArmPkg: introduce EDKII Platform Has ACPI Protocol, and plug-in library > > The presence of this protocol in the DXE protocol database implies that the platform provides the operating system with an ACPI-based hardware description. This is not necessarily mutually exclusive with a Device Tree-based hardware description. A platform driver is supposed to produce a single instance of the protocol (with NULL contents), if appropriate. > > The decision to produce the protocol is platform specific; for example, it could depend on an HII checkbox / underlying non-volatile UEFI variable. > > The protocol is meant to be consumed by > "MdeModulePkg/Universal/Acpi/AcpiTableDxe", through the PlatformHasAcpiLib plug-in. By linking this library into AcpiTableDxe via NULL resolution in the platform DSC, the platform makes EFI_ACPI_TABLE_PROTOCOL and (if enabled) EFI_ACPI_SDT_PROTOCOL dependent on the above dynamic decision. > > In turn, other (platform and universal) DXE drivers that produce ACPI tables will wait for EFI_ACPI_TABLE_PROTOCOL / EFI_ACPI_SDT_PROTOCOL, via DEPEX, protocol notify, or a simple gBS->LocateProtocol() in a "late enough" callback (such as Ready To Boot). > > Because this protocol is not standard, it is prefixed with EDKII / Edkii, as seen elsewhere in MdeModulePkg and SecurityPkg, for example. (ARM / Arm doesn't look future-proof enough; future UEFI platforms could face the same issue.) In addition, an effort is made to avoid the phrase "AcpiPlatform", as that belongs to drivers / libraries that produce platform specific ACPI content (as opposed to deciding whether the entire firmware will have access to EFI_ACPI_TABLE_PROTOCOL). > > Cc: Ard Biesheuvel > Cc: Leif Lindholm > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Laszlo Ersek > --- > ArmPkg/ArmPkg.dec | 4 ++ > ArmPkg/Library/PlatformHasAcpiLib/PlatformHasAcpiLib.inf | 40 ++++++++++++++++++++ > ArmPkg/Include/Protocol/PlatformHasAcpi.h | 34 +++++++++++++++++ > ArmPkg/Library/PlatformHasAcpiLib/PlatformHasAcpiLib.c | 36 ++++++++++++++++++ > 4 files changed, 114 insertions(+) > > diff --git a/ArmPkg/ArmPkg.dec b/ArmPkg/ArmPkg.dec index c4b4da2f95bb..0e49360a386a 100644 > --- a/ArmPkg/ArmPkg.dec > +++ b/ArmPkg/ArmPkg.dec > @@ -52,6 +52,10 @@ [Ppis] > ## Include/Ppi/ArmMpCoreInfo.h > gArmMpCoreInfoPpiGuid = { 0x6847cc74, 0xe9ec, 0x4f8f, {0xa2, 0x9d, 0xab, 0x44, 0xe7, 0x54, 0xa8, 0xfc} } > > +[Protocols] > + ## Include/Protocol/PlatformHasAcpi.h > + gEdkiiPlatformHasAcpiProtocolGuid = { 0xf0966b41, 0xc23f, 0x41b9, { 0x96, 0x04, 0x0f, 0xf7, 0xe1, 0x11, 0x96, 0x5a } } > + > [PcdsFeatureFlag.common] > gArmTokenSpaceGuid.PcdCpuDxeProduceDebugSupport|FALSE|BOOLEAN|0x00000001 > > diff --git a/ArmPkg/Library/PlatformHasAcpiLib/PlatformHasAcpiLib.inf b/ArmPkg/Library/PlatformHasAcpiLib/PlatformHasAcpiLib.inf > new file mode 100644 > index 000000000000..c83da4d8e98a > --- /dev/null > +++ b/ArmPkg/Library/PlatformHasAcpiLib/PlatformHasAcpiLib.inf > @@ -0,0 +1,40 @@ > +## @file > +# A hook-in library for MdeModulePkg/Universal/Acpi/AcpiTableDxe. > +# > +# Plugging this library instance into AcpiTableDxe makes # > +EFI_ACPI_TABLE_PROTOCOL and (if enabled) EFI_ACPI_SDT_PROTOCOL depend > +on the # platform's dynamic decision whether to expose an ACPI-based > +hardware # description to the operating system. > +# > +# Universal and platform specific DXE drivers that produce ACPI tables > +depend # on EFI_ACPI_TABLE_PROTOCOL / EFI_ACPI_SDT_PROTOCOL in turn. > +# > +# Copyright (C) 2017, Red Hat, Inc. > +# > +# This program and the accompanying materials are licensed and made > +available # under the terms and conditions of the BSD License which > +accompanies this # distribution. The full text of the license may be > +found at # http://opensource.org/licenses/bsd-license.php > +# > +# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, > +WITHOUT # WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. > +## > + > +[Defines] > + INF_VERSION = 1.25 > + BASE_NAME = PlatformHasAcpiLib > + FILE_GUID = 29beb028-0958-447b-be0a-12229235d77d > + MODULE_TYPE = BASE > + VERSION_STRING = 1.0 > + LIBRARY_CLASS = PlatformHasAcpiLib|DXE_DRIVER > + CONSTRUCTOR = PlatformHasAcpiInitialize > + > +[Sources] > + PlatformHasAcpiLib.c > + > +[Packages] > + ArmPkg/ArmPkg.dec > + MdePkg/MdePkg.dec > + > +[Depex] > + gEdkiiPlatformHasAcpiProtocolGuid > diff --git a/ArmPkg/Include/Protocol/PlatformHasAcpi.h b/ArmPkg/Include/Protocol/PlatformHasAcpi.h > new file mode 100644 > index 000000000000..3cd0cfe4515d > --- /dev/null > +++ b/ArmPkg/Include/Protocol/PlatformHasAcpi.h > @@ -0,0 +1,34 @@ > +/** @file > + EDKII Platform Has ACPI Protocol > + > + The presence of this protocol in the DXE protocol database implies > + that the platform provides the operating system with an ACPI-based > + hardware description. Note that this is not necessarily mutually > + exclusive with a Device Tree-based hardware description. A platform > + driver is supposed to produce a single instance of the protocol (with > + NULL contents), if appropriate. > + > + Copyright (C) 2017, Red Hat, Inc. > + > + This program and the accompanying materials are licensed and made > + available under the terms and conditions of the BSD License that > + accompanies this distribution. The full text of the license may be > + found at http://opensource.org/licenses/bsd-license.php. > + > + THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, > +WITHOUT > + WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. > +**/ > + > + > +#ifndef __EDKII_PLATFORM_HAS_ACPI_PROTOCOL_H__ > +#define __EDKII_PLATFORM_HAS_ACPI_PROTOCOL_H__ > + > +#define EDKII_PLATFORM_HAS_ACPI_PROTOCOL_GUID \ > + { \ > + 0xf0966b41, 0xc23f, 0x41b9, \ > + { 0x96, 0x04, 0x0f, 0xf7, 0xe1, 0x11, 0x96, 0x5a } \ > + } > + > +extern EFI_GUID gEdkiiPlatformHasAcpiProtocolGuid; > + > +#endif > diff --git a/ArmPkg/Library/PlatformHasAcpiLib/PlatformHasAcpiLib.c b/ArmPkg/Library/PlatformHasAcpiLib/PlatformHasAcpiLib.c > new file mode 100644 > index 000000000000..79072da21c2b > --- /dev/null > +++ b/ArmPkg/Library/PlatformHasAcpiLib/PlatformHasAcpiLib.c > @@ -0,0 +1,36 @@ > +/** @file > + A hook-in library for MdeModulePkg/Universal/Acpi/AcpiTableDxe. > + > + Plugging this library instance into AcpiTableDxe makes > + EFI_ACPI_TABLE_PROTOCOL and (if enabled) EFI_ACPI_SDT_PROTOCOL depend > + on the platform's dynamic decision whether to expose an ACPI-based > + hardware description to the operating system. > + > + Universal and platform specific DXE drivers that produce ACPI tables > + depend on EFI_ACPI_TABLE_PROTOCOL / EFI_ACPI_SDT_PROTOCOL in turn. > + > + Copyright (C) 2017, Red Hat, Inc. > + > + This program and the accompanying materials are licensed and made > + available under the terms and conditions of the BSD License which > + accompanies this distribution. The full text of the license may be > + found at http://opensource.org/licenses/bsd-license.php > + > + THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, > +WITHOUT > + WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. > +**/ > + > +#include > + > +RETURN_STATUS > +EFIAPI > +PlatformHasAcpiInitialize ( > + VOID > + ) > +{ > + // > + // Do nothing, just imbue AcpiTableDxe with an > + // EDKII_PLATFORM_HAS_ACPI_PROTOCOL dependency. > + // > + return RETURN_SUCCESS; > +} > -- > 2.9.3 > > > _______________________________________________ > edk2-devel mailing list > edk2-devel@lists.01.org > https://lists.01.org/mailman/listinfo/edk2-devel >