diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2017-10-09 14:48:39 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2017-10-12 13:23:14 +0100 |
| commit | 76eff04d166b8fe747adbe82de8b7e060e668ff9 (patch) | |
| tree | ed744634fa6e695f1595ab8beec13568f0af6bfb /target/arm/translate.c | |
| parent | dcf14dfb704519846f396a376339ebdb93eaf049 (diff) | |
| download | qemu-76eff04d166b8fe747adbe82de8b7e060e668ff9.tar.gz | |
target/arm: Implement SG instruction corner cases
The common situation of the SG instruction is that it is
executed from S&NSC memory by a CPU in NS state. That case
is handled by v7m_handle_execute_nsc(). However the instruction
also has defined behaviour in a couple of other cases:
* SG instruction in NS memory (behaves as a NOP)
* SG in S memory but CPU already secure (clears IT bits and
does nothing else)
* SG instruction in v8M without Security Extension (NOP)
These can be implemented in translate.c.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1507556919-24992-10-git-send-email-peter.maydell@linaro.org
Diffstat (limited to 'target/arm/translate.c')
| -rw-r--r-- | target/arm/translate.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/target/arm/translate.c b/target/arm/translate.c index 6634badb5a..4da1a4cbc6 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -9778,7 +9778,28 @@ static int disas_thumb2_insn(DisasContext *s, uint32_t insn) * - load/store doubleword, load/store exclusive, ldacq/strel, * table branch. */ - if (insn & 0x01200000) { + if (insn == 0xe97fe97f && arm_dc_feature(s, ARM_FEATURE_M) && + arm_dc_feature(s, ARM_FEATURE_V8)) { + /* 0b1110_1001_0111_1111_1110_1001_0111_111 + * - SG (v8M only) + * The bulk of the behaviour for this instruction is implemented + * in v7m_handle_execute_nsc(), which deals with the insn when + * it is executed by a CPU in non-secure state from memory + * which is Secure & NonSecure-Callable. + * Here we only need to handle the remaining cases: + * * in NS memory (including the "security extension not + * implemented" case) : NOP + * * in S memory but CPU already secure (clear IT bits) + * We know that the attribute for the memory this insn is + * in must match the current CPU state, because otherwise + * get_phys_addr_pmsav8 would have generated an exception. + */ + if (s->v8m_secure) { + /* Like the IT insn, we don't need to generate any code */ + s->condexec_cond = 0; + s->condexec_mask = 0; + } + } else if (insn & 0x01200000) { /* 0b1110_1000_x11x_xxxx_xxxx_xxxx_xxxx_xxxx * - load/store dual (post-indexed) * 0b1111_1001_x10x_xxxx_xxxx_xxxx_xxxx_xxxx |