On Fri, Sep 20, 2019 at 7:48 AM Bin Meng <bmeng.cn@gmail.com> wrote:
>
> If we are in debugger mode, skip the CSR privilege level checking
> so that we can read/write all CSRs. Otherwise we get:
>
> (gdb) p/x $mtvec
> Could not fetch register "mtvec"; remote failure reply 'E14'
>
> when the hart is currently in S-mode.
>
> Reported-by: Zong Li <zong.li@sifive.com>
> Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Alistair
> ---
>
> target/riscv/csr.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index f767ad2..974c9c2 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -801,7 +801,10 @@ int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value,
> #if !defined(CONFIG_USER_ONLY)
> int csr_priv = get_field(csrno, 0x300);
> int read_only = get_field(csrno, 0xC00) == 3;
> - if ((write_mask && read_only) || (env->priv < csr_priv)) {
> + if ((!env->debugger) && (env->priv < csr_priv)) {
> + return -1;
> + }
> + if (write_mask && read_only) {
> return -1;
> }
> #endif
> --
> 2.7.4
>
>