From 82604bd738ce34f37a1e0c679930ae27fa10ffc0 Mon Sep 17 00:00:00 2001 From: Thomas Heijligen Date: Sat, 19 Feb 2022 22:31:32 +0100 Subject: [PATCH] hwaccess: add endianness converting deserialization functions Add functions like `uint32_t read_le32(const void *base, size_t offset);` Read a 32 bit unsigned from a base with an offset. Having prototypes and a macro generated implementation makes it easier to read, understand and spot errors in one of them. Change-Id: Idde177acf8bc5f94cd046b6539dc31532c98e452 Signed-off-by: Thomas Heijligen Reviewed-on: https://review.coreboot.org/c/flashrom/+/31016 Tested-by: build bot (Jenkins) Reviewed-by: Angel Pons Reviewed-by: Nico Huber --- Makefile | 2 +- meson.build | 2 ++ platform.h | 13 +++++++++++++ platform/memaccess.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 58 insertions(+), 1 deletion(-) create mode 100644 platform/memaccess.c diff --git a/Makefile b/Makefile index f94f04688..bfa9c6799 100644 --- a/Makefile +++ b/Makefile @@ -378,7 +378,7 @@ CHIP_OBJS = jedec.o stm50.o w39.o w29ee011.o \ # Library code. LIB_OBJS = libflashrom.o layout.o flashrom.o udelay.o programmer.o programmer_table.o \ - helpers.o ich_descriptors.o fmap.o platform/endian_$(ENDIAN).o + helpers.o ich_descriptors.o fmap.o platform/endian_$(ENDIAN).o platform/memaccess.o ############################################################################### diff --git a/meson.build b/meson.build index c84c5ded9..5a6bc2ad7 100644 --- a/meson.build +++ b/meson.build @@ -135,6 +135,8 @@ if cc.check_header('sys/utsname.h') add_project_arguments('-DHAVE_UTSNAME=1', language : 'c') endif +srcs += 'platform/memaccess.c' + if host_machine.endian() == 'little' srcs += 'platform/endian_little.c' add_project_arguments('-D__FLASHROM_LITTLE_ENDIAN__=1', language : 'c') diff --git a/platform.h b/platform.h index 4f2a4c174..cf73c2923 100644 --- a/platform.h +++ b/platform.h @@ -22,6 +22,7 @@ #ifndef __PLATFORM_H__ #define __PLATFORM_H__ 1 +#include #include /* swap bytes */ @@ -100,4 +101,16 @@ uint16_t be_to_cpu16(uint16_t value); uint32_t be_to_cpu32(uint32_t value); uint64_t be_to_cpu64(uint64_t value); +/* read value from base at offset in little endian */ +uint8_t read_le8 (const void *base, size_t offset); +uint16_t read_le16(const void *base, size_t offset); +uint32_t read_le32(const void *base, size_t offset); +uint64_t read_le64(const void *base, size_t offset); + +/* read value from base at offset in big endian */ +uint8_t read_be8 (const void *base, size_t offset); +uint16_t read_be16(const void *base, size_t offset); +uint32_t read_be32(const void *base, size_t offset); +uint64_t read_be64(const void *base, size_t offset); + #endif /* !__PLATFORM_H__ */ diff --git a/platform/memaccess.c b/platform/memaccess.c new file mode 100644 index 000000000..44ef41084 --- /dev/null +++ b/platform/memaccess.c @@ -0,0 +1,42 @@ +/* + * This file is part of the flashrom project. + * + * Copyright (C) 2016 secunet Security Networks AG + * (written by Thomas Heijligen ) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include "../platform.h" + +/* + * macro to return endian aware read function + * + * `___read(le, 8)` + * expands to + * `uint8_t read_le8 (const void *const base, const size_t offset) + * { return le_to_cpu8 (*(uint8_t *)((uintptr_t)base + offset)); }` + */ +#define ___read(endian, bits) \ + uint##bits##_t read_##endian##bits (const void *const base, const size_t offset) \ + { return endian##_to_cpu##bits (*(uint##bits##_t *)((uintptr_t)base + offset)); } + +/* read value from base at offset in little endian */ +___read(le, 8) +___read(le, 16) +___read(le, 32) +___read(le, 64) + +/* read value from base at offset in big endian */ +___read(be, 8) +___read(be, 16) +___read(be, 32) +___read(be, 64)