From 446c81abf8e0572b8d5d23fe056516ac62af278d Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Thu, 21 Jan 2016 14:15:08 +0000 Subject: target-arm: Properly support EL2 and EL3 in arm_el_is_aa64() Support EL2 and EL3 in arm_el_is_aa64() by implementing the logic for checking the SCR_EL3 and HCR_EL2 register-width bits as appropriate to determine the register width of lower exception levels. Signed-off-by: Peter Maydell Reviewed-by: Edgar E. Iglesias --- target-arm/cpu.h | 33 ++++++++++++++++++++++++--------- 1 file changed, 24 insertions(+), 9 deletions(-) (limited to 'target-arm') diff --git a/target-arm/cpu.h b/target-arm/cpu.h index 5f8134296b..b8b3364615 100644 --- a/target-arm/cpu.h +++ b/target-arm/cpu.h @@ -969,18 +969,33 @@ static inline bool arm_is_secure(CPUARMState *env) /* Return true if the specified exception level is running in AArch64 state. */ static inline bool arm_el_is_aa64(CPUARMState *env, int el) { - /* We don't currently support EL2, and this isn't valid for EL0 - * (if we're in EL0, is_a64() is what you want, and if we're not in EL0 - * then the state of EL0 isn't well defined.) + /* This isn't valid for EL0 (if we're in EL0, is_a64() is what you want, + * and if we're not in EL0 then the state of EL0 isn't well defined.) */ - assert(el == 1 || el == 3); + assert(el >= 1 && el <= 3); + bool aa64 = arm_feature(env, ARM_FEATURE_AARCH64); - /* AArch64-capable CPUs always run with EL1 in AArch64 mode. This - * is a QEMU-imposed simplification which we may wish to change later. - * If we in future support EL2 and/or EL3, then the state of lower - * exception levels is controlled by the HCR.RW and SCR.RW bits. + /* The highest exception level is always at the maximum supported + * register width, and then lower levels have a register width controlled + * by bits in the SCR or HCR registers. */ - return arm_feature(env, ARM_FEATURE_AARCH64); + if (el == 3) { + return aa64; + } + + if (arm_feature(env, ARM_FEATURE_EL3)) { + aa64 = aa64 && (env->cp15.scr_el3 & SCR_RW); + } + + if (el == 2) { + return aa64; + } + + if (arm_feature(env, ARM_FEATURE_EL2) && !arm_is_secure_below_el3(env)) { + aa64 = aa64 && (env->cp15.hcr_el2 & HCR_RW); + } + + return aa64; } /* Function for determing whether guest cp register reads and writes should -- cgit v1.2.1