From f48ad5b29d6f291b4f3679ff5fb7b5beae10d6fa Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Thu, 2 Jun 2016 13:38:30 +0100 Subject: arm: Correctly check FP/SIMD access permission in aarch32 The current implementation of aarch32 FP/SIMD in gem5 assumes that EL1 and higher are all 32-bit. This breaks interprocessing since an aarch64 EL1 uses different enable/disable bits. This change updates the permission checks to according to what is prescribed by the ARM ARM. Change-Id: Icdcef31b00644cfeebec00216b3993aa1de12b88 Signed-off-by: Andreas Sandberg Reviewed-by: Mitch Hayenga Reviewed-by: Nathanael Premillieu --- src/arch/arm/insts/static_inst.cc | 134 +++++++++++++++++++++++++++++++++++++- src/arch/arm/insts/static_inst.hh | 43 +++++++++++- 2 files changed, 175 insertions(+), 2 deletions(-) (limited to 'src/arch/arm/insts') diff --git a/src/arch/arm/insts/static_inst.cc b/src/arch/arm/insts/static_inst.cc index 6fdd07ff6..d4ea1bcdf 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 ARM Limited + * Copyright (c) 2010-2014, 2016 ARM Limited * Copyright (c) 2013 Advanced Micro Devices, Inc. * All rights reserved * @@ -595,4 +595,136 @@ ArmStaticInst::generateDisassembly(Addr pc, printMnemonic(ss); return ss.str(); } + + +Fault +ArmStaticInst::advSIMDFPAccessTrap64(ExceptionLevel el) const +{ + switch (el) { + case EL1: + return std::make_shared(machInst, 0x1E00000, + EC_TRAPPED_SIMD_FP); + case EL2: + return std::make_shared(machInst, 0x1E00000, + EC_TRAPPED_SIMD_FP); + case EL3: + return std::make_shared(machInst, 0x1E00000, + EC_TRAPPED_SIMD_FP); + + default: + panic("Illegal EL in advSIMDFPAccessTrap64\n"); + } +} + + +Fault +ArmStaticInst::checkFPAdvSIMDTrap64(ThreadContext *tc, CPSR cpsr) const +{ + const ExceptionLevel el = (ExceptionLevel) (uint8_t)cpsr.el; + + if (ArmSystem::haveVirtualization(tc) && el <= EL2) { + HCPTR cptrEnCheck = tc->readMiscReg(MISCREG_CPTR_EL2); + if (cptrEnCheck.tfp) + return advSIMDFPAccessTrap64(EL2); + } + + if (ArmSystem::haveSecurity(tc)) { + HCPTR cptrEnCheck = tc->readMiscReg(MISCREG_CPTR_EL3); + if (cptrEnCheck.tfp) + return advSIMDFPAccessTrap64(EL3); + } + + return NoFault; +} + +Fault +ArmStaticInst::checkFPAdvSIMDEnabled64(ThreadContext *tc, + CPSR cpsr, CPACR cpacr) const +{ + const ExceptionLevel el = (ExceptionLevel) (uint8_t)cpsr.el; + if ((el == EL0 && cpacr.fpen != 0x3) || + (el == EL1 && !(cpacr.fpen & 0x1))) + return advSIMDFPAccessTrap64(EL1); + + return checkFPAdvSIMDTrap64(tc, cpsr); +} + +Fault +ArmStaticInst::checkAdvSIMDOrFPEnabled32(ThreadContext *tc, + CPSR cpsr, CPACR cpacr, + NSACR nsacr, FPEXC fpexc, + bool fpexc_check, bool advsimd) const +{ + const bool have_virtualization = ArmSystem::haveVirtualization(tc); + const bool have_security = ArmSystem::haveSecurity(tc); + const bool is_secure = inSecureState(tc); + const ExceptionLevel cur_el = opModeToEL(currOpMode(tc)); + + if (cur_el == EL0 && ELIs64(tc, EL1)) + return checkFPAdvSIMDEnabled64(tc, cpsr, cpacr); + + uint8_t cpacr_cp10 = cpacr.cp10; + bool cpacr_asedis = cpacr.asedis; + + if (have_security && !ELIs64(tc, EL3) && !is_secure) { + if (nsacr.nsasedis) + cpacr_asedis = true; + if (nsacr.cp10 == 0) + cpacr_cp10 = 0; + } + + if (cur_el != EL2) { + if (advsimd && cpacr_asedis) + return disabledFault(); + + if ((cur_el == EL0 && cpacr_cp10 != 0x3) || + (cur_el != EL0 && !(cpacr_cp10 & 0x1))) + return disabledFault(); + } + + if (fpexc_check && !fpexc.en) + return disabledFault(); + + // -- aarch32/exceptions/traps/AArch32.CheckFPAdvSIMDTrap -- + + if (have_virtualization && !is_secure && ELIs64(tc, EL2)) + return checkFPAdvSIMDTrap64(tc, cpsr); + + if (have_virtualization && !is_secure) { + HCPTR hcptr = tc->readMiscReg(MISCREG_HCPTR); + bool hcptr_cp10 = hcptr.tcp10; + bool hcptr_tase = hcptr.tase; + + if (have_security && !ELIs64(tc, EL3) && !is_secure) { + if (nsacr.nsasedis) + hcptr_tase = true; + if (nsacr.cp10) + hcptr_cp10 = true; + } + + if ((advsimd && hcptr_tase) || hcptr_cp10) { + const uint32_t iss = advsimd ? (1 << 5) : 0xA; + if (cur_el == EL2) { + return std::make_shared( + machInst, iss, + EC_TRAPPED_HCPTR, mnemonic); + } else { + return std::make_shared( + machInst, iss, + EC_TRAPPED_HCPTR); + } + + } + } + + if (have_security && ELIs64(tc, EL3)) { + HCPTR cptrEnCheck = tc->readMiscReg(MISCREG_CPTR_EL3); + if (cptrEnCheck.tfp) + return advSIMDFPAccessTrap64(EL3); + } + + return NoFault; +} + + } diff --git a/src/arch/arm/insts/static_inst.hh b/src/arch/arm/insts/static_inst.hh index d4684c78f..9ca64d1fe 100644 --- a/src/arch/arm/insts/static_inst.hh +++ b/src/arch/arm/insts/static_inst.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010-2013 ARM Limited + * Copyright (c) 2010-2013, 2016 ARM Limited * All rights reserved * * The license below extends only to copyright in the software and shall @@ -363,6 +363,47 @@ class ArmStaticInst : public StaticInst mnemonic, true); } + /** + * Trap an access to Advanced SIMD or FP registers due to access + * control bits. + * + * See aarch64/exceptions/traps/AArch64.AdvSIMDFPAccessTrap in the + * ARM ARM psueodcode library. + * + * @param el Target EL for the trap + */ + Fault advSIMDFPAccessTrap64(ExceptionLevel el) const; + + + /** + * Check an Advaned SIMD access against CPTR_EL2 and CPTR_EL3. + * + * See aarch64/exceptions/traps/AArch64.CheckFPAdvSIMDTrap in the + * ARM ARM psueodcode library. + */ + Fault checkFPAdvSIMDTrap64(ThreadContext *tc, CPSR cpsr) const; + + /** + * Check an Advaned SIMD access against CPACR_EL1, CPTR_EL2, and + * CPTR_EL3. + * + * See aarch64/exceptions/traps/AArch64.CheckFPAdvSIMDEnabled in the + * ARM ARM psueodcode library. + */ + Fault checkFPAdvSIMDEnabled64(ThreadContext *tc, + CPSR cpsr, CPACR cpacr) const; + + /** + * Check if a VFP/SIMD access from aarch32 should be allowed. + * + * See aarch32/exceptions/traps/AArch32.CheckAdvSIMDOrFPEnabled in the + * ARM ARM psueodcode library. + */ + Fault checkAdvSIMDOrFPEnabled32(ThreadContext *tc, + CPSR cpsr, CPACR cpacr, + NSACR nsacr, FPEXC fpexc, + bool fpexc_check, bool advsimd) const; + public: virtual void annotateFault(ArmFault *fault) {} -- cgit v1.2.3