Unverified Commit e2165905 authored by Michael Clark's avatar Michael Clark
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RISC-V: Allow S-mode mxr access when priv ISA >= v1.10 



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 <sagark@eecs.berkeley.edu>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Alistair Francis <Alistair.Francis@wdc.com>
Signed-off-by: default avatarMichael Clark <mjc@sifive.com>
Reviewed-by: default avatarAlistair Francis <alistair.francis@wdc.com>
parent 67185dad

target/riscv/op_helper.c

+5 −2
Original line number Diff line number Diff line
@@ -234,7 +234,10 @@ 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;