diff options
authorPeter Maydell <peter.maydell@linaro.org>2017-09-04 15:21:51 +0100
committerPeter Maydell <peter.maydell@linaro.org>2017-09-04 15:21:51 +0100
commit0e2845689ebdb4ea7174f96f6797e2d8942bd114 (patch)
parent03ae85f858fc46495258a5dd4551fff2c34bd495 (diff)
target/arm: Don't trap WFI/WFE for M profile
M profile cores can never trap on WFI or WFE instructions. Check for M profile in check_wfx_trap() to ensure this. The existing code will do the right thing for v7M cores because the hcr_el2 and scr_el3 registers will be all-zeroes and so we won't attempt to trap, but when we start setting ARM_FEATURE_V8 for v8M cores the v8A handling of SCTLR.nTWE and .nTWI will not give the right results. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 1501692241-23310-3-git-send-email-peter.maydell@linaro.org
1 files changed, 5 insertions, 0 deletions
diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
index 2a85666579..5a94a5f2ba 100644
--- a/target/arm/op_helper.c
+++ b/target/arm/op_helper.c
@@ -370,6 +370,11 @@ static inline int check_wfx_trap(CPUARMState *env, bool is_wfe)
int cur_el = arm_current_el(env);
uint64_t mask;
+ if (arm_feature(env, ARM_FEATURE_M)) {
+ /* M profile cores can never trap WFI/WFE. */
+ return 0;
+ }
/* If we are currently in EL0 then we need to check if SCTLR is set up for
* WFx instructions being trapped to EL1. These trap bits don't exist in v7.