diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2016-02-23 15:36:44 +0000 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2016-02-26 15:09:42 +0000 |
| commit | 10eacda787ac9990dc22d4437b289200c819712c (patch) | |
| tree | caa862b1bf1e43cb95f4a913abce22f442d33236 /target-arm | |
| parent | af393ffc6da116b9dd4c70901bad1f4cafb1773d (diff) | |
target-arm: Make Monitor->NS PL1 mode changes illegal if HCR.TGE is 1
If HCR.TGE is 1 then mode changes via CPS and MSR from Monitor to
NonSecure PL1 modes are illegal mode changes. Implement this check
in bad_mode_switch().
(We don't currently implement HCR.TGE, but this is the only missing
check from the v8 ARM ARM G1.9.3 and so it's worth adding now; the
rest of the HCR.TGE checks can be added later as necessary.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <serge.fdrv@gmail.com>
Message-id: 1455556977-3644-12-git-send-email-peter.maydell@linaro.org
Diffstat (limited to 'target-arm')
| -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) |