[toolchain] Move to LLVM Toolchain for OpenTitan Peripheral Support

CMakeLists.txt

@@ -3,6 +3,7 @@
 # SPDX-License-Identifier: Apache-2.0
 #
 # Moritz Scherer <[email protected]>
+# Viviane Potocnik <[email protected]>
 
 cmake_minimum_required(VERSION 3.13)
 
@@ -11,11 +12,14 @@ set(CMAKE_C_STANDARD 99)
 # SCHEREMO: Needed to skip compiler test, which doesn't support baremetal targets
 set(CMAKE_C_COMPILER_WORKS 1)
 
+set(CMAKE_EXPORT_COMPILE_COMMANDS TRUE)
+set(CMAKE_VERBOSE_MAKEFILE TRUE)
+
 # SCHEREMO: Help most IDE's LSPs find definitions
 set(CMAKE_EXPORT_COMPILE_COMMANDS 1)
 
 # SCHEREMO: This toolchain file is only used for test compilation!
-set(CMAKE_TOOLCHAIN_FILE cmake/toolchain_gcc.cmake)
+set(CMAKE_TOOLCHAIN_FILE cmake/toolchain_llvm.cmake)
 
 set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
 set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)

README.md

@@ -21,6 +21,19 @@ which riscv32-unknown-elf-gcc
 ```
 is not empty.
 
+## LLVM Toolchain
+
+The applications are built using the RISC-V LLVM toolchain. On IIS systems, users can use the pre-installed LLVM version 12.0.1.
+
+Outside of IIS systems, you need to install LLVM version 12.0.1 or later to ensure compatibility.
+
+The correct version of the toolchain can be verified by running
+```
+llvm-config --version
+```
+
+## Building the SDK
+
 To build the SDK and all tests contained in the SDK, run
 
 ```

cmake/toolchain_llvm.cmake

@@ -0,0 +1,20 @@
+# Copyright 2024 ETH Zurich and University of Bologna.
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+#
+# Viviane Potocnik <[email protected]>
+
+set(CMAKE_EXECUTABLE_SUFFIX ".elf")
+
+set(CMAKE_SYSTEM_NAME Generic)
+
+set(CMAKE_C_COMPILER clang)
+set(CMAKE_CXX_COMPILER clang++)
+set(CMAKE_ASM_COMPILER ${CMAKE_C_COMPILER})
+
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --target=riscv32-unknown-elf")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} --target=riscv32-unknown-elf")
+
+set(CMAKE_OBJCOPY llvm-objcopy)
+set(CMAKE_OBJDUMP llvm-objdump)
+set(CMAKE_AR llvm-ar)