From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-x22d.google.com (mail-it0-x22d.google.com [IPv6:2607:f8b0:4001:c0b::22d]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 2F7EE21DFA7B0 for ; Fri, 24 Mar 2017 15:41:25 -0700 (PDT) Received: by mail-it0-x22d.google.com with SMTP id y18so8326888itc.1 for ; Fri, 24 Mar 2017 15:41:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=HzHk3aoJZMbGF4qgU9FjNWyEvBbrIQS3OK6j1CmbjXc=; b=argpo5Hb+5aPBVVlkhupuog1TU+2142NRrIm9IFc6Ng70lIoeP2JC7wxOOUgC2zEmC 4poIKCfHkfRQjw7L8owFWAzPJM0oT4iCrpZuiGjrOKWstf1F2Cf0aqmD80Z/QvpktiXP L8uS+KwKPTZLgmpsH9naBJjFF9uzq57PjTGMo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=HzHk3aoJZMbGF4qgU9FjNWyEvBbrIQS3OK6j1CmbjXc=; b=qNb/0ieRCUNpIDxz2Bz5Z9r0SOg/ahvX6Hid+D41uo/5yuVZRqmRHjL3EY86Nnx1D9 eNs5suTNQy9azxoZtN6SiyIA5e+hG5euuZ0Lh3S/H551P74KPY7S4CqeXtK0zVO5H3aL xzvjLjp3HuTrtWFuvIgbcjRiPfyujomT3qtU4qpMuLdticXAUJLvmXGNaQuzDLqPGHNO Kv2k6g95HffbIFpOSHPntfVZXUetrmwHWuJjgA7WCougGEQGGXtff7PZ20HE75LFqLco 83diJiPOmiJWXK+RL9jpzB4GM0oX+ZaE1w10120MXQeNS8t3gl6EJCgrAX0eeNMsqLLy MHxQ== X-Gm-Message-State: AFeK/H0uAiMxQbHhyFPaX0Lif8UCRGUfgsDnuYDDeq/1gUf2p26CrWjdBs20rJh97d47K5+mVGs72gMa/GPTvyQD X-Received: by 10.107.132.155 with SMTP id o27mr10266671ioi.138.1490395284377; Fri, 24 Mar 2017 15:41:24 -0700 (PDT) MIME-Version: 1.0 Received: by 10.107.10.27 with HTTP; Fri, 24 Mar 2017 15:41:23 -0700 (PDT) In-Reply-To: <20170324223819.11377-5-lersek@redhat.com> References: <20170324223819.11377-1-lersek@redhat.com> <20170324223819.11377-5-lersek@redhat.com> From: Ard Biesheuvel Date: Fri, 24 Mar 2017 22:41:23 +0000 Message-ID: To: Laszlo Ersek Cc: edk2-devel-01 , Feng Tian , Leif Lindholm , Star Zeng Subject: Re: [PATCH v3 04/12] MdeModulePkg: introduce EDKII Platform Has ACPI GUID 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: Fri, 24 Mar 2017 22:41:25 -0000 Content-Type: text/plain; charset=UTF-8 On 24 March 2017 at 22:38, Laszlo Ersek wrote: > The presence of this GUID in the PPI database, and/or in the DXE protocol > database (as dictated by the platform's needs in these firmware phases) > implies that the platform provides the operating system with an ACPI-based > hardware description. This is not necessarily exclusive with other types > of hardware description (for example, a Device Tree-based one). > > A platform PEIM and/or DXE driver is supposed to produce a single instance > of the PPI and/or protocol (with NULL contents), if appropriate. The > decision to produce the PPI and/or protocol is platform specific; for > example, in the DXE phase, it could depend on an HII checkbox / underlying > non-volatile UEFI variable. > > In the DXE phase, the protocol is meant to be depended-upon by > "MdeModulePkg/Universal/Acpi/AcpiTableDxe", indirectly: > > * In the long term, interested platforms will establish this dependency by > hooking an (upcoming) NULL-class DepexLib instance into AcpiTableDxe in > their DSC files, pointing DepexLib's DEPEX through a FixedAtBuild PCD to > the GUID introduced here. (For the prerequisite BaseTools feature, refer > to ). > > * In the short term, an interested platform may hook a private NULL-class > library instance (called e.g. "PlatformHasAcpiLib") into AcpiTableDxe. > Such a library instance would be a specialization of the above described > generic DepexLib, with the DEPEX open-coded on the GUID introduced here. > > Either way, the platform makes EFI_ACPI_TABLE_PROTOCOL and (if enabled) > EFI_ACPI_SDT_PROTOCOL dependent on the platform's dynamic decision to > produce or not to produce a NULL protocol instance with this GUID. > > 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 GUID is not standard, it is prefixed with EDKII / Edkii, as > seen elsewhere in MdeModulePkg and SecurityPkg. 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, or any similar facilities in the PEI phase). > > Cc: Ard Biesheuvel > Cc: Feng Tian > Cc: Leif Lindholm > Cc: Star Zeng > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Laszlo Ersek Reviewed-by: Ard Biesheuvel > --- > > Notes: > v3: > - rename gEdkiiPlatformHasAcpiProtocolGuid to gEdkiiPlatformHasAcpiGuid > [Star] > - update commit message and code comments to reflect possible use as a > PPI as well [Star] > - move GUID from ArmPkg to MdeModulePkg [Leif, Ard] > - split PlatformHasAcpiLib to a separate patch [Star] > > MdeModulePkg/MdeModulePkg.dec | 3 ++ > MdeModulePkg/Include/Guid/PlatformHasAcpi.h | 35 ++++++++++++++++++++ > 2 files changed, 38 insertions(+) > > diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec > index 626e479f5e45..2d94881206d3 100644 > --- a/MdeModulePkg/MdeModulePkg.dec > +++ b/MdeModulePkg/MdeModulePkg.dec > @@ -382,6 +382,9 @@ [Guids] > gEdkiiNonDiscoverableUhciDeviceGuid = { 0xA8CDA0A2, 0x4F37, 0x4A1B, {0x8E, 0x10, 0x8E, 0xF3, 0xCC, 0x3B, 0xF3, 0xA8 } } > gEdkiiNonDiscoverableXhciDeviceGuid = { 0xB1BE0BC5, 0x6C28, 0x442D, {0xAA, 0x37, 0x15, 0x1B, 0x42, 0x57, 0xBD, 0x78 } } > > + ## Include/Guid/PlatformHasAcpi.h > + gEdkiiPlatformHasAcpiGuid = { 0xf0966b41, 0xc23f, 0x41b9, { 0x96, 0x04, 0x0f, 0xf7, 0xe1, 0x11, 0x96, 0x5a } } > + > [Ppis] > ## Include/Ppi/AtaController.h > gPeiAtaControllerPpiGuid = { 0xa45e60d1, 0xc719, 0x44aa, { 0xb0, 0x7a, 0xaa, 0x77, 0x7f, 0x85, 0x90, 0x6d }} > diff --git a/MdeModulePkg/Include/Guid/PlatformHasAcpi.h b/MdeModulePkg/Include/Guid/PlatformHasAcpi.h > new file mode 100644 > index 000000000000..ad517821375d > --- /dev/null > +++ b/MdeModulePkg/Include/Guid/PlatformHasAcpi.h > @@ -0,0 +1,35 @@ > +/** @file > + EDKII Platform Has ACPI GUID > + > + A NULL protocol instance with this GUID in the DXE protocol database, and/or > + a NULL PPI with this GUID in the PPI database, implies that the platform > + provides the operating system with an ACPI-based hardware description. Note > + that this is not necessarily exclusive with different kinds of hardware > + description (for example, a Device Tree-based one). A platform driver and/or > + PEIM is supposed to produce a single instance of the protocol and/or PPI > + (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_H__ > +#define __EDKII_PLATFORM_HAS_ACPI_H__ > + > +#define EDKII_PLATFORM_HAS_ACPI_GUID \ > + { \ > + 0xf0966b41, 0xc23f, 0x41b9, \ > + { 0x96, 0x04, 0x0f, 0xf7, 0xe1, 0x11, 0x96, 0x5a } \ > + } > + > +extern EFI_GUID gEdkiiPlatformHasAcpiGuid; > + > +#endif > -- > 2.9.3 > >