diff options
Diffstat (limited to 'target-arm/helper.c')
| -rw-r--r-- | target-arm/helper.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/target-arm/helper.c b/target-arm/helper.c index 24ea48ecdc..3d7fda15e2 100644 --- a/target-arm/helper.c +++ b/target-arm/helper.c @@ -5216,6 +5216,7 @@ static int bad_mode_switch(CPUARMState *env, int mode, CPSRWriteType write_type) switch (mode) { case ARM_CPU_MODE_USR: + return 0; case ARM_CPU_MODE_SYS: case ARM_CPU_MODE_SVC: case ARM_CPU_MODE_ABT: @@ -5225,6 +5226,15 @@ static int bad_mode_switch(CPUARMState *env, int mode, CPSRWriteType write_type) /* Note that we don't implement the IMPDEF NSACR.RFR which in v7 * allows FIQ mode to be Secure-only. (In v8 this doesn't exist.) */ + /* If HCR.TGE is set then changes from Monitor to NS PL1 via MSR + * and CPS are treated as illegal mode changes. + */ + if (write_type == CPSRWriteByInstr && + (env->cp15.hcr_el2 & HCR_TGE) && + (env->uncached_cpsr & CPSR_M) == ARM_CPU_MODE_MON && + !arm_is_secure_below_el3(env)) { + return 1; + } return 0; case ARM_CPU_MODE_HYP: return !arm_feature(env, ARM_FEATURE_EL2) |