diff options
| author | Richard Henderson <richard.henderson@linaro.org> | 2019-01-14 23:57:59 +0000 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@sifive.com> | 2019-02-11 15:56:21 -0800 |
| commit | 533b8f8877d4e3e8bf2b57e633a84afe27c14429 (patch) | |
| tree | 6cde2c1332bdfdeeb41ad262ac46310c4422d0e3 /target/riscv/csr.c | |
| parent | 83a71719903cbfb683fd916bb555620e8b272140 (diff) | |
RISC-V: Mark mstatus.fs dirty
Modifed from Richard Henderson's patch [1] to integrate
with the new control and status register implementation.
[1] https://lists.nongnu.org/archive/html/qemu-devel/2018-03/msg07034.html
Note: the f* CSRs already mark mstatus.FS dirty using
env->mstatus |= mstatus.FS so the bug in the first
spin of this patch has been fixed in a prior commit.
Signed-off-by: Michael Clark <mjc@sifive.com>
Reviewed-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Co-authored-by: Michael Clark <mjc@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Diffstat (limited to 'target/riscv/csr.c')
| -rw-r--r-- | target/riscv/csr.c | 12 |
1 files changed, 0 insertions, 12 deletions
diff --git a/target/riscv/csr.c b/target/riscv/csr.c index 5e7e7d16b8..5714147689 100644 --- a/target/riscv/csr.c +++ b/target/riscv/csr.c @@ -317,18 +317,6 @@ static int write_mstatus(CPURISCVState *env, int csrno, target_ulong val) mstatus = (mstatus & ~mask) | (val & mask); - /* Note: this is a workaround for an issue where mstatus.FS - does not report dirty after floating point operations - that modify floating point state. This workaround is - technically compliant with the RISC-V Privileged - specification as it is legal to return only off, or dirty. - at the expense of extra floating point save/restore. */ - - /* FP is always dirty or off */ - if (mstatus & MSTATUS_FS) { - mstatus |= MSTATUS_FS; - } - int dirty = ((mstatus & MSTATUS_FS) == MSTATUS_FS) | ((mstatus & MSTATUS_XS) == MSTATUS_XS); mstatus = set_field(mstatus, MSTATUS_SD, dirty); |