Tianocore/edk2.git/PrmPkg/Samples/PrmSampleHardwareAccessModule/Hpet.h, branch master

PrmPkg: Replace include guards with #pragma once

2026-02-23T21:01:28+00:00

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

PrmPkg: Apply uncrustify changes

2022-04-05T00:42:38+00:00

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=3737 Apply uncrustify changes to .c/.h files in PrmPkg. Cc: Andrew Fish Cc: Kang Gao Cc: Michael D Kinney Cc: Michael Kubacki Cc: Leif Lindholm Cc: Benjamin You Cc: Liu Yun Cc: Ankit Sinha Cc: Nate DeSimone Signed-off-by: Michael Kubacki Acked-by: Michael D Kinney Acked-by: Liming Gao Acked-by: Leif Lindholm Reviewed-by: Ankit Sinha

PrmPkg/HardwareAccessModuleConfigLib: Add initial library

2022-04-05T00:42:38+00:00

Adds a PRM module configuration library for PrmSampleHardwareAccessModule that demonstrates marking a runtime MMIO range. In the case of this sample module, the range used is for HPET. Cc: Andrew Fish Cc: Kang Gao Cc: Michael D Kinney Cc: Michael Kubacki Cc: Leif Lindholm Cc: Benjamin You Cc: Liu Yun Cc: Ankit Sinha Cc: Nate DeSimone Signed-off-by: Michael Kubacki Acked-by: Michael D Kinney Acked-by: Liming Gao Acked-by: Leif Lindholm Reviewed-by: Ankit Sinha

PrmPkg: Add initial PrmSampleHardwareAccessModule

2022-04-05T00:42:38+00:00

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=3812 Adds a sample PRM module that demonstrates: 1. How to write a PRM module 2. How to use multiple PRM handlers in a module 3. How to use a basic PRM OS service 4. MSR access at OS runtime Note: This module contains a PRM handler to read from the HPET MMIO range but the memory map changes needed for this to succeed are currently not implemented. These will be implemented in a future change. Cc: Andrew Fish Cc: Kang Gao Cc: Michael D Kinney Cc: Michael Kubacki Cc: Leif Lindholm Cc: Benjamin You Cc: Liu Yun Cc: Ankit Sinha Cc: Nate DeSimone Signed-off-by: Michael Kubacki Acked-by: Michael D Kinney Acked-by: Liming Gao Acked-by: Leif Lindholm Reviewed-by: Ankit Sinha