diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2018-05-04 18:05:51 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2018-05-04 18:05:51 +0100 |
| commit | b1e5336a9899016c53d59eba53ebf6abcc21995c (patch) | |
| tree | e91047012a06cb8b1a8dd5253ada6a51efeee8b0 /target | |
| parent | a82929a251481af1467569810ec309b57558f7fe (diff) | |
| download | qemu-b1e5336a9899016c53d59eba53ebf6abcc21995c.tar.gz | |
target/arm: Implement v8M VLLDM and VLSTM
For v8M the instructions VLLDM and VLSTM support lazy saving
and restoring of the secure floating-point registers. Even
if the floating point extension is not implemented, these
instructions must act as NOPs in Secure state, so they can
be used as part of the secure-to-nonsecure call sequence.
Fixes: https://bugs.launchpad.net/qemu/+bug/1768295
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180503105730.5958-1-peter.maydell@linaro.org
Diffstat (limited to 'target')
| -rw-r--r-- | target/arm/translate.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/target/arm/translate.c b/target/arm/translate.c index 9bc2ce1a0b..ad208867a7 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -10795,8 +10795,23 @@ static void disas_thumb2_insn(DisasContext *s, uint32_t insn) /* Coprocessor. */ if (arm_dc_feature(s, ARM_FEATURE_M)) { /* We don't currently implement M profile FP support, - * so this entire space should give a NOCP fault. + * so this entire space should give a NOCP fault, with + * the exception of the v8M VLLDM and VLSTM insns, which + * must be NOPs in Secure state and UNDEF in Nonsecure state. */ + if (arm_dc_feature(s, ARM_FEATURE_V8) && + (insn & 0xffa00f00) == 0xec200a00) { + /* 0b1110_1100_0x1x_xxxx_xxxx_1010_xxxx_xxxx + * - VLLDM, VLSTM + * We choose to UNDEF if the RAZ bits are non-zero. + */ + if (!s->v8m_secure || (insn & 0x0040f0ff)) { + goto illegal_op; + } + /* Just NOP since FP support is not implemented */ + break; + } + /* All other insns: NOCP */ gen_exception_insn(s, 4, EXCP_NOCP, syn_uncategorized(), default_exception_el(s)); break; |