For v8M floating point support, transitions from Secure to Non-secure state via BLNS and BLXNS must clear the CONTROL.SFPA bit. (This corresponds to the pseudocode BranchToNS() function.)
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> Reviewed-by: Richard Henderson <richard.hender...@linaro.org> Message-id: 20190416125744.27770-13-peter.mayd...@linaro.org --- target/arm/helper.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/target/arm/helper.c b/target/arm/helper.c index 547898581a2..088852ceb96 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -7819,6 +7819,9 @@ void HELPER(v7m_bxns)(CPUARMState *env, uint32_t dest) /* translate.c should have made BXNS UNDEF unless we're secure */ assert(env->v7m.secure); + if (!(dest & 1)) { + env->v7m.control[M_REG_S] &= ~R_V7M_CONTROL_SFPA_MASK; + } switch_v7m_security_state(env, dest & 1); env->thumb = 1; env->regs[15] = dest & ~1; @@ -7876,6 +7879,7 @@ void HELPER(v7m_blxns)(CPUARMState *env, uint32_t dest) */ write_v7m_exception(env, 1); } + env->v7m.control[M_REG_S] &= ~R_V7M_CONTROL_SFPA_MASK; switch_v7m_security_state(env, 0); env->thumb = 1; env->regs[15] = dest; -- 2.20.1