On Wed, Apr 25, 2018 at 5:10 PM Michael Clark <m...@sifive.com> wrote:
> The mstatus.MXR alias in sstatus should only be writable
> by S-mode if the privileged ISA version >= v1.10. Also MXR
> was masked in sstatus CSR read but not sstatus CSR writes.
> Now we correctly mask sstatus.mxr in both read and write.
> Cc: Sagar Karandikar <sag...@eecs.berkeley.edu>
> Cc: Bastian Koppelmann <kbast...@mail.uni-paderborn.de>
> Cc: Palmer Dabbelt <pal...@sifive.com>
> Cc: Alistair Francis <alistair.fran...@wdc.com>
> Signed-off-by: Michael Clark <m...@sifive.com>
Reviewed-by: Alistair Francis <alistair.fran...@wdc.com>
Alistair
> ---
> target/riscv/op_helper.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
> diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c
> index b81b9b6..88c263a 100644
> --- a/target/riscv/op_helper.c
> +++ b/target/riscv/op_helper.c
> @@ -236,7 +236,10 @@ void csr_write_helper(CPURISCVState *env,
target_ulong val_to_write,
> target_ulong ms = env->mstatus;
> target_ulong mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_UIE
> | SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS
> - | SSTATUS_SUM | SSTATUS_MXR | SSTATUS_SD;
> + | SSTATUS_SUM | SSTATUS_SD;
> + if (env->priv_ver >= PRIV_VERSION_1_10_0) {
> + mask |= SSTATUS_MXR;
> + }
> ms = (ms & ~mask) | (val_to_write & mask);
> csr_write_helper(env, ms, CSR_MSTATUS);
> break;
> @@ -439,7 +442,7 @@ target_ulong csr_read_helper(CPURISCVState *env,
target_ulong csrno)
> case CSR_SSTATUS: {
> target_ulong mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_UIE
> | SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS
> - | SSTATUS_SUM | SSTATUS_SD;
> + | SSTATUS_SUM | SSTATUS_SD;
> if (env->priv_ver >= PRIV_VERSION_1_10_0) {
> mask |= SSTATUS_MXR;
> }
> --
> 2.7.0
