opensbi.git/Makefile, branch v1.0

Makefile: Improve the method to disable -m(no-)save-restore option

2021-12-16T03:57:22Z

The commit 69d7e53 disables the -m(no-)save-restore option for clang, but clang11 supports this option. This patch uses the output information of the compiler to check whether the compiler supports this option. Signed-off-by: Xiang W Reviewed-by: Anup Patel

Makefile: Fix -msave-restore compile warning with CLANG-10 (or lower)

2021-12-11T12:07:26Z

The riscv target of CLANG-10 (or lower) does not support the -m(no-)save-restore option so we get compile warnings. This patch fixes compile warning by using -m(no-)save-restore option only for GCC. Signed-off-by: Anup Patel Reviewed-by: Dong Du

Makefile: Add build time and compiler info string

2021-10-20T09:40:52Z

When we are doing opensbi development, we want to know the build time and compiler info for debug purpose. To enable this message, please add "BUILD_INFO=y", like: ``` make BUILD_INFO=y ``` NOTE: Using `BUILD_INFO=y` without specifying SOURCE_DATE_EPOCH will violate "reproducible builds". So it's ONLY for development and debug purpose, and should NOT be used in a product which follows "reproducible builds". Signed-off-by: Wei Fu Reviewed-by: Anup Patel Reviewed-by: Alistair Francis

Makefile: Manually forward RELAX_FLAG to the assembler when linking with LLD

2021-07-27T08:59:31Z

When generating code with -mno-relax, GCC puts .option norelax in the generated assembly, and so doesn’t bother passing on -mno-relax to the assembler. This has the unfortunate effect that, when using GCC to assemble hand-written assembly, -mno-relax does nothing, and we have to pass -Wa,-mno-relax to manually forward it to the assembler. This is an old GCC bug that was fixed [1] recently. For the time being, let's pass "-Wa,-mno-relax" to ASFLAGS for the GCC + LLD combination to work, e.g.: $ make CC=riscv64-unknown-elf-gcc LLVM=1 PLATFORM=generic [1] https://github.com/gcc-mirror/gcc/commit/3b0a7d624e64eeb81e4d5e8c62c46d86ef521857 Signed-off-by: Bin Meng Reviewed-by: Anup Patel

lib: utils: Drop dependency on libgcc by importing part of FreeBSD's libquad

2021-07-11T15:31:44Z

We only need libgcc for 64-bit division on RV32. Whilst GCC toolchains bundle libgcc, Clang toolchains tend not to ship libclang_rt.builtins given every compiler is a cross-compiler for every target and so you would need a silly number of builds of it, with only the native library available; only vendor-provided Clang toolchains specifically for bare metal cross-compiling are likely to provide it. Thus, import part of FreeBSD's implementation of the division support functions needed and stop linking against libgcc. Signed-off-by: Jessica Clarke Reviewed-by: Anup Patel Tested-by: Anup Patel

Makefile: Support building with Clang and LLVM binutils

2021-07-11T14:52:55Z

This is intended to mirror the Linux kernel. Building with CC=clang will use Clang as the compiler but default to using the existing binutils. Building with LLVM=1 will default to using Clang and LLVM binutils. Whilst GCC will accept the -N linker option and forward it on to the linker, Clang will not, and so in order to support both compilers we must use -Wl, to forward it to the linker as is required for most other linker options. Note that there is currently a bug when using Clang as the compiler and riscv64-linux-gnu-ld as the linker for FW_PIC=y. At first glance this appears to be a bug in GNU binutils, but this could also be Clang or OpenSBI at fault in some subtle way. Thus, for now, advise that this combination be avoided. Signed-off-by: Jessica Clarke Reviewed-by: Anup Patel Tested-by: Anup Patel

firmware: Only default FW_PIC to y if supported

2021-07-11T14:33:06Z

Bare-metal GNU ld does not support PIE, so if using it this will result in a failure to build. Instead, default to FW_PIC=n if not supported. Note that an explicit FW_PIC=y is not overridden, to ensure the build fails rather than silently producing a position-dependent binary. Signed-off-by: Jessica Clarke Reviewed-by: Bin Meng Tested-by: Bin Meng Reviewed-by: Anup Patel

Makefile: unconditionally disable SSP

2021-05-19T11:07:50Z

Though -nostdlib is passed in CFLAGS, -fno-stack-protector must also be passed to avoid linking errors related to undefined references to '__stack_chk_guard' and '__stack_chk_fail' if toolchain enforces -fstack-protector. Fixes: - https://gitlab.com/kubu93/buildroot/-/jobs/1247043359 Signed-off-by: Fabrice Fontaine Reviewed-by: Bin Meng Reviewed-by: Xiang W

include: headers: Replace ASSEMBLY with ASSEMBLER

2021-03-22T10:32:48Z

GCC has already a predefined macro __ASSEMBLER__ therefore, it can be used without the need to define a new flag with -D__ASSEMBLY__. This is useful when adding the library to projects having a build system such one can build without the need to make changes. THe build system does not use the Makefile in the sources tree. Signed-off-by: Marouene Boubakri Signed-off-by: Anup Patel

firmware: Support position independent execution

2021-03-19T09:30:50Z

Enable OpenSBI to support position independent execution. Because the position independent code will cause an additional GOT reference when accessing the global variables, it will reduce performance a bit. Therefore, the position independent execution is disabled by default. Users can through specifying "FW_PIC=y" on the make command to enable this feature. In theory, after enabling position-independent execution, the OpenSBI can run at arbitrary address with appropriate alignment. Therefore, the original relocation mechanism will be skipped. In other words, OpenSBI will directly run at the load address without any code movement. Signed-off-by: Vincent Chen Reviewed-by: Anup Patel