How to make riscv-gcc compile new csr register？

riscv-software-src / riscv-tools

RISC-V Tools (ISA Simulator and Tests)

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How to make riscv-gcc compile new csr register？ #289

Closed 245950258 closed 5 years ago

245950258 commented 5 years ago

I am working on rocket-chip. Recently, I added a new CSR register to my rocket-chip. However, it looks like that the RISCV-GCC can't compile my program.
So, I want to know if the RISCV-TOOLS supports to add a new CSR register.

jim-wilson commented 5 years ago

The toolchain is riscv-gnu-toolchain, not riscv-tools.

You can always use the CSR register number. If you want to use the CSR name, then you need to modify binutils to add assembler/disassembler support for the new name. In binutils, see the file include/opcode/riscv-opc.h and look for example at the CSR_MSTATUS support. You need two lines, one which gives the register number, and one which maps the register number to the name string.

245950258 commented 5 years ago

Thank you for helping me.