On Sat, Aug 21, 2021 at 1:43 AM Richard Henderson <richard.hender...@linaro.org> wrote: > > Introduce csrr and csrw helpers, for read-only and write-only insns. > > Note that we do not properly implement this in riscv_csrrw, in that > we cannot distinguish true read-only (rs1 == 0) from any other zero > write_mask another source register -- this should still raise an > exception for read-only registers. > > Only issue gen_io_start for CF_USE_ICOUNT. > Use ctx->zero for csrrc. > Use get_gpr and dest_gpr. > > Reviewed-by: Bin Meng <bmeng...@gmail.com> > Signed-off-by: Richard Henderson <richard.hender...@linaro.org> > --- > target/riscv/helper.h | 6 +- > target/riscv/op_helper.c | 18 +-- > target/riscv/insn_trans/trans_rvi.c.inc | 172 +++++++++++++++++------- > 3 files changed, 131 insertions(+), 65 deletions(-) >
When testing Linux kernel boot, there was a segment fault in the helper_csrw() path where ret_value pointer is now NULL, and some CSR write op does not test ret_value. Regards, Bin
