Tianocore/edk2.git - EDK II (mirror)

Age	Commit message (Collapse)	Author	Files	Lines
2026-02-24	UefiPayloadPkg: Replace include guards with #pragma once	Michael Kubacki	1	-4/+1
	Replace traditional `#ifndef`/`#define`/`#endif` include guards with `#pragma` once. `#pragma once` is a widely supported preprocessor directive that prevents header files from being included multiple times. It is supported by all toolchains used to build edk2: GCC, Clang/LLVM, and MSVC. Compared to macro-based include guards, `#pragma once`: - Eliminates the risk of macro name collisions or copy/paste errors where two headers inadvertently use the same guard macro. - Eliminate inconsistency in the way include guard macros are named (e.g., some files use `__FILE_H__`, others use `FILE_H_`, etc.). - Reduces boilerplate (three lines replaced by one). - Avoids polluting the macro namespace with guard symbols. - Can improve build times as the preprocessor can skip re-opening the file entirely, rather than re-reading it to find the matching `#endif` ("multiple-include optimization"). - Note that some compilers may already optimize traditional include guards, by recognzining the idiomatic pattern. This change is made acknowledging that overall portability of the code will technically be reduced, as `#pragma once` is not part of the C/C++ standards. However, this is considered acceptable given: 1. edk2 already defines a subset of supported compilers in BaseTools/Conf/tools_def.template, all of which have supported `#pragma once` for over two decades. 2. There have been concerns raised to the project about inconsistent include guard naming and potential macro collisions. Approximate compiler support dates: - MSVC: Supported since Visual C++ 4.2 (1996) - GCC: Supported since 3.4 (2004) (http://gnu.ist.utl.pt/software/gcc/gcc-3.4/changes.html) - Clang (LLVM based): Since initial release in 2007 Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
2025-08-25	UefiPayloadPkg/SmmStore: Add API to read/write/erase any flash block	Sergii Dmytruk	2	-21/+157
	This allows reusing SMMSTORE protocol for the purpose of firmware updates. Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>
2025-04-09	UefiPayloadPkg: Add SmmStoreLib	Patrick Rudolph	4	-0/+617
	Implement all of the FVB protocol functions on top of the SmmStore as a library. The library consumes the introduced gEfiSmmStoreInfoHobGuid. The SMI handler uses a fixed communication buffer in reserved DRAM. To initiate a transaction you must write to the I/O APM_CNT port. Tests on Intel(R) Xeon(R) E-2288G CPU @ 3.70G showed that the SMI isn't triggered with a probability of 1:40 of all cases when called in a tight loop. The CPU continues running and the SMI is triggered asynchronously a few clock cycles later. coreboot only handles synchronous APM request and does nothing on asynchronous APM triggers. As there's no livesign from SMM it's impossible to tell if the handler has run. Just wait a bit and try again to trigger a synchronous SMI. Tests confirmed that out of 5 million tries the SMI is now always handled. When a synchronous SMI happens with the correct write to the APM_CNT port, the ebx register is checked first that it doesn't point to SMRAM. If it doesn't it's used to read in the arguments that define an SmmStore transaction. The SMI handler will only operate on a predefined and memory mapped region in the boot media. Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com> Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>