arch-arm: Correct Illegal Exception Return detection
Fixed Illegal Exception Return detection, which was not
covering all the documented cases.
Change-Id: If08ddc1490d1c0a1fccee1489d116384770ce0a5
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7223
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
diff --git a/src/arch/arm/insts/static_inst.cc b/src/arch/arm/insts/static_inst.cc
index eeda3ad..61f31e5 100644
--- a/src/arch/arm/insts/static_inst.cc
+++ b/src/arch/arm/insts/static_inst.cc
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2010-2014, 2016-2017 ARM Limited
+ * Copyright (c) 2010-2014, 2016-2018 ARM Limited
* Copyright (c) 2013 Advanced Micro Devices, Inc.
* All rights reserved
*
@@ -897,27 +897,40 @@
const OperatingMode cur_mode = (OperatingMode) (uint8_t)cpsr.mode;
const ExceptionLevel target_el = opModeToEL(mode);
+
+ HCR hcr = ((HCR)tc->readMiscReg(MISCREG_HCR_EL2));
+ SCR scr = ((SCR)tc->readMiscReg(MISCREG_SCR_EL3));
+
if (target_el > opModeToEL(cur_mode))
return true;
- if (target_el == EL3 && !ArmSystem::haveSecurity(tc))
+ if (!ArmSystem::haveEL(tc, target_el))
return true;
- if (target_el == EL2 && !ArmSystem::haveVirtualization(tc))
+ if (target_el == EL1 && ArmSystem::haveEL(tc, EL2) && scr.ns && hcr.tge)
+ return true;
+
+ if (target_el == EL2 && ArmSystem::haveEL(tc, EL3) && !scr.ns)
+ return true;
+
+ bool spsr_mode_is_aarch32 = (spsr.width == 1);
+ bool known, target_el_is_aarch32;
+ std::tie(known, target_el_is_aarch32) = ELUsingAArch32K(tc, target_el);
+ assert(known || (target_el == EL0 && ELIs64(tc, EL1)));
+
+ if (known && (spsr_mode_is_aarch32 != target_el_is_aarch32))
return true;
if (!spsr.width) {
// aarch64
if (!ArmSystem::highestELIs64(tc))
return true;
-
if (spsr & 0x2)
return true;
if (target_el == EL0 && spsr.sp)
return true;
- if (target_el == EL2 && !((SCR)tc->readMiscReg(MISCREG_SCR_EL3)).ns)
- return false;
} else {
+ // aarch32
return badMode32(mode);
}