diff --git a/src/arch/arm/faults.cc b/src/arch/arm/faults.cc index 9ce2e2da4..9fdd58da0 100644 --- a/src/arch/arm/faults.cc +++ b/src/arch/arm/faults.cc @@ -74,6 +74,9 @@ template<> ArmFault::FaultVals ArmFaultVals::vals = template<> ArmFault::FaultVals ArmFaultVals::vals = {"Pipe Flush", 0x00, MODE_SVC, 0, 0, true, true}; // some dummy values +template<> ArmFault::FaultVals ArmFaultVals::vals = + {"ReExec Flush", 0x00, MODE_SVC, 0, 0, true, true}; // some dummy values + Addr ArmFault::getVector(ThreadContext *tc) { @@ -225,6 +228,17 @@ FlushPipe::invoke(ThreadContext *tc, StaticInstPtr inst) { tc->pcState(pc); } +void +ReExec::invoke(ThreadContext *tc, StaticInstPtr inst) { + DPRINTF(Faults, "Invoking ReExec Fault\n"); + + // Set the PC to then the faulting instruction. + // Net effect is simply squashing all instructions including this + // instruction and refetching/rexecuting current instruction + PCState pc = tc->pcState(); + tc->pcState(pc); +} + template void AbortFault::invoke(ThreadContext *tc, StaticInstPtr inst); template void AbortFault::invoke(ThreadContext *tc, diff --git a/src/arch/arm/faults.hh b/src/arch/arm/faults.hh index 633e74eae..8df8d0abf 100644 --- a/src/arch/arm/faults.hh +++ b/src/arch/arm/faults.hh @@ -242,6 +242,16 @@ class FlushPipe : public ArmFaultVals StaticInstPtr inst = StaticInst::nullStaticInstPtr); }; +// A fault that flushes the pipe, including the faulting instructions +class ReExec : public ArmFaultVals +{ + public: + ReExec() {} + void invoke(ThreadContext *tc, + StaticInstPtr inst = StaticInst::nullStaticInstPtr); +}; + + static inline Fault genMachineCheckFault() { return new Reset(); diff --git a/src/arch/arm/table_walker.cc b/src/arch/arm/table_walker.cc index e2207e26b..2d0e323f6 100644 --- a/src/arch/arm/table_walker.cc +++ b/src/arch/arm/table_walker.cc @@ -114,8 +114,16 @@ TableWalker::walk(RequestPtr _req, ThreadContext *_tc, uint8_t _cid, TLB::Mode _ currState = new WalkerState(); currState->tableWalker = this; - } - else if (_timing) { + } else if (_timing) { + // This is a translation that was completed and then faulted again + // because some underlying parameters that affect the translation + // changed out from under us (e.g. asid). It will either be a + // misprediction, in which case nothing will happen or we'll use + // this fault to re-execute the faulting instruction which should clean + // up everything. + if (currState->vaddr == _req->getVaddr()) { + return new ReExec; + } panic("currState should always be empty in timing mode!\n"); } diff --git a/src/arch/arm/tlb.cc b/src/arch/arm/tlb.cc index f1c8ae41a..ccbca3d9c 100644 --- a/src/arch/arm/tlb.cc +++ b/src/arch/arm/tlb.cc @@ -446,8 +446,10 @@ Fault TLB::translateFs(RequestPtr req, ThreadContext *tc, Mode mode, Translation *translation, bool &delay, bool timing) { - if (!miscRegValid) + if (!miscRegValid) { updateMiscReg(tc); + DPRINTF(TLBVerbose, "TLB variables changed!\n"); + } Addr vaddr = req->getVaddr(); uint32_t flags = req->getFlags(); @@ -456,7 +458,7 @@ TLB::translateFs(RequestPtr req, ThreadContext *tc, Mode mode, bool is_write = (mode == Write); bool is_priv = isPriv && !(flags & UserMode); - DPRINTF(TLBVerbose, "CPSR is user:%d UserMode:%d\n", + DPRINTF(TLBVerbose, "CPSR is priv:%d UserMode:%d\n", isPriv, flags & UserMode); // If this is a clrex instruction, provide a PA of 0 with no fault // This will force the monitor to set the tracked address to 0