[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-arm] [PATCH 02/15] target/arm: Don't trap WFI/WFE for M profile
From: |
Peter Maydell |
Subject: |
[Qemu-arm] [PATCH 02/15] target/arm: Don't trap WFI/WFE for M profile |
Date: |
Wed, 2 Aug 2017 17:43:48 +0100 |
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 <address@hidden>
---
target/arm/op_helper.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
index 2a85666..5a94a5f 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.
*/
--
2.7.4
- [Qemu-arm] [PATCH 05/15] hw/intc/armv7m_nvic.c: Remove out of date comment, (continued)