From 63bbc8929d778c15f5c7479819226c19a42dc2b9 Mon Sep 17 00:00:00 2001 From: Gabe Black Date: Wed, 8 Nov 2006 13:58:00 -0500 Subject: [PATCH] First cut at full blown SPARC faults. There are a few details that are missing. --HG-- extra : convert_revision : 8023db1479cb9bf99fc9edfeb521c4e5b581f895 --- src/arch/sparc/faults.cc | 240 ++++++++++++++++++++++++++++++++++----- 1 file changed, 211 insertions(+), 29 deletions(-) diff --git a/src/arch/sparc/faults.cc b/src/arch/sparc/faults.cc index ebd9926b2..e895c02db 100644 --- a/src/arch/sparc/faults.cc +++ b/src/arch/sparc/faults.cc @@ -33,6 +33,7 @@ #include "arch/sparc/faults.hh" #include "arch/sparc/isa_traits.hh" +#include "arch/sparc/types.hh" #include "base/bitfield.hh" #include "base/trace.hh" #include "config/full_system.hh" @@ -268,26 +269,133 @@ template<> SparcFaultBase::FaultVals {"page_table_fault", 0x0000, 0, {SH, SH, SH}}; #endif +/** + * This causes the thread context to enter RED state. This causes the side + * effects which go with entering RED state because of a trap. + */ + +void enterREDState(ThreadContext *tc) +{ + //@todo Disable the mmu? + //@todo Disable watchpoints? + MiscReg HPSTATE = tc->readMiscReg(MISCREG_HPSTATE); + //HPSTATE.red = 1 + HPSTATE |= (1 << 5); + //HPSTATE.hpriv = 1 + HPSTATE |= (1 << 2); + tc->setMiscReg(MISCREG_HPSTATE, HPSTATE); +} + +/** + * This sets everything up for a RED state trap except for actually jumping to + * the handler. + */ + +void doREDFault(ThreadContext *tc, TrapType tt) +{ + MiscReg TL = tc->readMiscReg(MISCREG_TL); + MiscReg TSTATE = tc->readMiscReg(MISCREG_TSTATE); + MiscReg PSTATE = tc->readMiscReg(MISCREG_PSTATE); + MiscReg HPSTATE = tc->readMiscReg(MISCREG_HPSTATE); + MiscReg CCR = tc->readMiscReg(MISCREG_CCR); + MiscReg ASI = tc->readMiscReg(MISCREG_ASI); + MiscReg CWP = tc->readMiscReg(MISCREG_CWP); + MiscReg CANSAVE = tc->readMiscReg(MISCREG_CANSAVE); + MiscReg GL = tc->readMiscReg(MISCREG_GL); + MiscReg PC = tc->readPC(); + MiscReg NPC = tc->readNextPC(); + + TL++; + + //set TSTATE.gl to gl + replaceBits(TSTATE, 42, 40, GL); + //set TSTATE.ccr to ccr + replaceBits(TSTATE, 39, 32, CCR); + //set TSTATE.asi to asi + replaceBits(TSTATE, 31, 24, ASI); + //set TSTATE.pstate to pstate + replaceBits(TSTATE, 20, 8, PSTATE); + //set TSTATE.cwp to cwp + replaceBits(TSTATE, 4, 0, CWP); + + //Write back TSTATE + tc->setMiscReg(MISCREG_TSTATE, TSTATE); + + //set TPC to PC + tc->setMiscReg(MISCREG_TPC, PC); + //set TNPC to NPC + tc->setMiscReg(MISCREG_TNPC, NPC); + + //set HTSTATE.hpstate to hpstate + tc->setMiscReg(MISCREG_HTSTATE, HPSTATE); + + //TT = trap type; + tc->setMiscReg(MISCREG_TT, tt); + + //Update GL + tc->setMiscRegWithEffect(MISCREG_GL, min(GL+1, MaxGL)); + + //set PSTATE.mm to 00 + //set PSTATE.pef to 1 + PSTATE |= (1 << 4); + //set PSTATE.am to 0 + PSTATE &= ~(1 << 3); + //set PSTATE.priv to 0 + PSTATE &= ~(1 << 2); + //set PSTATE.ie to 0 + PSTATE &= ~(1 << 1); + //set PSTATE.cle to 0 + PSTATE &= ~(1 << 9); + //PSTATE.tle is unchanged + //XXX Where is the tct bit? + //set PSTATE.tct to 0 + tc->setMiscReg(MISCREG_PSTATE, PSTATE); + + //set HPSTATE.red to 1 + HPSTATE |= (1 << 5); + //set HPSTATE.hpriv to 1 + HPSTATE |= (1 << 2); + //set HPSTATE.ibe to 0 + HPSTATE &= ~(1 << 10); + //set HPSTATE.tlz to 0 + HPSTATE &= ~(1 << 0); + tc->setMiscReg(MISCREG_HPSTATE, HPSTATE); + + bool changedCWP = true; + if(tt == 0x24) + CWP++; + else if(0x80 <= tt && tt <= 0xbf) + CWP += (CANSAVE + 2); + else if(0xc0 <= tt && tt <= 0xff) + CWP--; + else + changedCWP = false; + + if(changedCWP) + { + CWP = (CWP + NWindows) % NWindows; + tc->setMiscRegWithEffect(MISCREG_CWP, CWP); + } +} + /** * This sets everything up for a normal trap except for actually jumping to - * the handler. It will need to be expanded to include the state machine in - * the manual. Right now it assumes that traps will always be to the - * privileged level. + * the handler. */ -void doNormalFault(ThreadContext *tc, TrapType tt) +void doNormalFault(ThreadContext *tc, TrapType tt, bool gotoHpriv) { - uint64_t TL = tc->readMiscReg(MISCREG_TL); - uint64_t TSTATE = tc->readMiscReg(MISCREG_TSTATE); - uint64_t PSTATE = tc->readMiscReg(MISCREG_PSTATE); - uint64_t HPSTATE = tc->readMiscReg(MISCREG_HPSTATE); - uint64_t CCR = tc->readMiscReg(MISCREG_CCR); - uint64_t ASI = tc->readMiscReg(MISCREG_ASI); - uint64_t CWP = tc->readMiscReg(MISCREG_CWP); - uint64_t CANSAVE = tc->readMiscReg(MISCREG_CANSAVE); - uint64_t GL = tc->readMiscReg(MISCREG_GL); - uint64_t PC = tc->readPC(); - uint64_t NPC = tc->readNextPC(); + MiscReg TL = tc->readMiscReg(MISCREG_TL); + MiscReg TSTATE = tc->readMiscReg(MISCREG_TSTATE); + MiscReg PSTATE = tc->readMiscReg(MISCREG_PSTATE); + MiscReg HPSTATE = tc->readMiscReg(MISCREG_HPSTATE); + MiscReg CCR = tc->readMiscReg(MISCREG_CCR); + MiscReg ASI = tc->readMiscReg(MISCREG_ASI); + MiscReg CWP = tc->readMiscReg(MISCREG_CWP); + MiscReg CANSAVE = tc->readMiscReg(MISCREG_CANSAVE); + MiscReg GL = tc->readMiscReg(MISCREG_GL); + MiscReg PC = tc->readPC(); + MiscReg NPC = tc->readNextPC(); //Increment the trap level TL++; @@ -321,10 +429,10 @@ void doNormalFault(ThreadContext *tc, TrapType tt) tc->setMiscReg(MISCREG_TT, tt); //Update the global register level - if(1/*We're delivering the trap in priveleged mode*/) - tc->setMiscReg(MISCREG_GL, min(GL+1, MaxGL)); + if(!gotoHpriv) + tc->setMiscRegWithEffect(MISCREG_GL, min(GL+1, MaxPGL)); else - tc->setMiscReg(MISCREG_GL, min(GL+1, MaxPGL)); + tc->setMiscRegWithEffect(MISCREG_GL, min(GL+1, MaxGL)); //PSTATE.mm is unchanged //PSTATE.pef = whether or not an fpu is present @@ -333,7 +441,7 @@ void doNormalFault(ThreadContext *tc, TrapType tt) PSTATE |= (1 << 4); //PSTATE.am = 0 PSTATE &= ~(1 << 3); - if(1/*We're delivering the trap in priveleged mode*/) + if(!gotoHpriv) { //PSTATE.priv = 1 PSTATE |= (1 << 2); @@ -354,7 +462,7 @@ void doNormalFault(ThreadContext *tc, TrapType tt) //XXX Where exactly is this field? tc->setMiscReg(MISCREG_PSTATE, PSTATE); - if(0/*We're delivering the trap in hyperprivileged mode*/) + if(gotoHpriv) { //HPSTATE.red = 0 HPSTATE &= ~(1 << 5); @@ -383,6 +491,29 @@ void doNormalFault(ThreadContext *tc, TrapType tt) } } +void getREDVector(Addr & PC, Addr & NPC) +{ + const Addr RSTVAddr = 0xFFFFFFFFF0000000ULL; + PC = RSTVAddr | 0xA0; + NPC = PC + sizeof(MachInst); +} + +void getHyperVector(Addr & PC, Addr & NPC, MiscReg TT) +{ + Addr HTBA ; + PC = (HTBA & ~mask(14)) | ((TT << 5) & mask(14)); + NPC = PC + sizeof(MachInst); +} + +void getPrivVector(Addr & PC, Addr & NPC, MiscReg TT, MiscReg TL) +{ + Addr TBA ; + PC = (TBA & ~mask(15)) | + (TL > 1 ? (1 << 14) : 0) | + ((TT << 5) & mask(14)); + NPC = PC + sizeof(MachInst); +} + #if FULL_SYSTEM void SparcFaultBase::invoke(ThreadContext * tc) @@ -390,11 +521,64 @@ void SparcFaultBase::invoke(ThreadContext * tc) FaultBase::invoke(tc); countStat()++; - //Use the SPARC trap state machine + //We can refer to this to see what the trap level -was-, but something + //in the middle could change it in the regfile out from under us. + MiscReg TL = tc->readMiscReg(MISCREG_TL); + MiscReg TT = tc->readMiscReg(MISCREG_TT); + MiscReg PSTATE = tc->readMiscReg(MISCREG_PSTATE); + MiscReg HPSTATE = tc->readMiscReg(MISCREG_HPSTATE); + + Addr PC, NPC; + + PrivilegeLevel current; + if(!(PSTATE & (1 << 2))) + current = User; + else if(!(HPSTATE & (1 << 2))) + current = Privileged; + else + current = Hyperprivileged; + + PrivilegeLevel level = getNextLevel(current); + + if(HPSTATE & (1 << 5) || TL == MaxTL - 1) + { + getREDVector(PC, NPC); + enterREDState(tc); + doREDFault(tc, TT); + } + else if(TL == MaxTL) + { + //Do error_state somehow? + //Probably inject a WDR fault using the interrupt mechanism. + //What should the PC and NPC be set to? + } + else if(TL > MaxPTL && level == Privileged) + { + //guest_watchdog fault + doNormalFault(tc, trapType(), true); + getHyperVector(PC, NPC, 2); + } + else if(level == Hyperprivileged) + { + doNormalFault(tc, trapType(), true); + getHyperVector(PC, NPC, trapType()); + } + else + { + doNormalFault(tc, trapType(), false); + getPrivVector(PC, NPC, trapType(), TL+1); + } + + tc->setPC(PC); + tc->setNextPC(NPC); + tc->setNextNPC(NPC + sizeof(MachInst)); } void PowerOnReset::invoke(ThreadContext * tc) { + //First, enter RED state. + enterREDState(tc); + //For SPARC, when a system is first started, there is a power //on reset Trap which sets the processor into the following state. //Bits that aren't set aren't defined on startup. @@ -426,17 +610,15 @@ void PowerOnReset::invoke(ThreadContext * tc) */ } -#endif - -#if !FULL_SYSTEM +#else // !FULL_SYSTEM void SpillNNormal::invoke(ThreadContext *tc) { - doNormalFault(tc, trapType()); + doNormalFault(tc, trapType(), false); Process *p = tc->getProcessPtr(); - //This will only work in faults from a SparcLiveProcess + //XXX This will only work in faults from a SparcLiveProcess SparcLiveProcess *lp = dynamic_cast(p); assert(lp); @@ -449,15 +631,15 @@ void SpillNNormal::invoke(ThreadContext *tc) void FillNNormal::invoke(ThreadContext *tc) { - doNormalFault(tc, trapType()); + doNormalFault(tc, trapType(), false); Process * p = tc->getProcessPtr(); - //This will only work in faults from a SparcLiveProcess + //XXX This will only work in faults from a SparcLiveProcess SparcLiveProcess *lp = dynamic_cast(p); assert(lp); - //The adjust the PC and NPC + //Then adjust the PC and NPC Addr fillStart = lp->readFillStart(); tc->setPC(fillStart); tc->setNextPC(fillStart + sizeof(MachInst)); -- 2.30.2