From dbaeca276b82c56282f2f256abf15a553022602c Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Thu, 2 Jul 2015 06:36:19 +0000 Subject: [PATCH] IntelFrameworkModulePkg: AcpiS3SaveDxe: prepare for End-of-Dxe callback We are preparing for detaching the S3Ready() functionality from the EFI_ACPI_S3_SAVE_PROTOCOL.S3Save() protocol member function. Instead, we will hook the same logic to the End-of-Dxe event group. The EFI_ACPI_S3_SAVE_PROTOCOL has another member: GetLegacyMemorySize(). According to the documenation, This function returns the size of the legacy memory (meaning below 1 MB) that is required during an S3 resume. Before the Framework-based firmware transfers control to the OS, it has to transition from flat mode into real mode in case the OS supplies only a real-mode waking vector. This transition requires a certain amount of legacy memory. After getting the size of legacy memory below, the caller is responsible for allocating the legacy memory below 1 MB according to the size that is returned. The specific implementation of allocating the legacy memory is out of the scope of this specification. When EFI_ACPI_S3_SAVE_PROTOCOL.S3Save() is called, the address of the legacy memory allocated above must be passed to it, in the LegacyMemoryAddress parameter. In practice however: - The S3Ready() function ignores the LegacyMemoryAddress completely. - No code in the edk2 tree calls EFI_ACPI_S3_SAVE_PROTOCOL.GetLegacyMemorySize(), ever. - All callers of EFI_ACPI_S3_SAVE_PROTOCOL.S3Save() in the edk2 tree pass a NULL LegacyMemoryAddress: BdsLibBootViaBootOption() [IntelFrameworkModulePkg/Library/GenericBdsLib/BdsBoot.c] OnReadyToBoot() [Vlv2TbltDevicePkg/AcpiPlatform/AcpiPlatform.c] InstallReadyToLock() [Vlv2TbltDevicePkg/Library/PlatformBdsLib/BdsPlatform.c] BdsLibBootViaBootOption() [Vlv2TbltDevicePkg/Override/IntelFrameworkModulePkg/Library/GenericBdsLib/BdsBoot.c] For this reason, ASSERT() explicitly that LegacyGetS3MemorySize() is never called, and that the LegacyMemoryAddress parameter is always NULL. This fact is important to capture in the code, because in the End-of-Dxe callback, no LegacyMemoryAddress parameter can be taken. So let's make it clear that we actually don't even have any use for that parameter. Cc: Yao Jiewen Cc: Jeff Fan Cc: David Wei Cc: Tim He Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17804 6f19259b-4bc3-4df7-8a09-765794883524 --- .../Universal/Acpi/AcpiS3SaveDxe/AcpiS3Save.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/IntelFrameworkModulePkg/Universal/Acpi/AcpiS3SaveDxe/AcpiS3Save.c b/IntelFrameworkModulePkg/Universal/Acpi/AcpiS3SaveDxe/AcpiS3Save.c index 6de1871f67..ac3e9470bd 100644 --- a/IntelFrameworkModulePkg/Universal/Acpi/AcpiS3SaveDxe/AcpiS3Save.c +++ b/IntelFrameworkModulePkg/Universal/Acpi/AcpiS3SaveDxe/AcpiS3Save.c @@ -2,6 +2,7 @@ This is an implementation of the ACPI S3 Save protocol. This is defined in S3 boot path specification 0.9. +Copyright (c) 2015, Red Hat, Inc.
Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.
This program and the accompanying materials @@ -422,6 +423,8 @@ LegacyGetS3MemorySize ( OUT UINTN *Size ) { + ASSERT (FALSE); + if (Size == NULL) { return EFI_INVALID_PARAMETER; } @@ -469,6 +472,8 @@ S3Ready ( } AlreadyEntered = TRUE; + ASSERT (LegacyMemoryAddress == NULL); + AcpiS3Context = AllocateMemoryBelow4G (EfiReservedMemoryType, sizeof(*AcpiS3Context)); ASSERT (AcpiS3Context != NULL); AcpiS3ContextBuffer = (EFI_PHYSICAL_ADDRESS)(UINTN)AcpiS3Context; -- 2.39.2