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/*
* Copyright (c) 2003-2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Gabe Black
* Kevin Lim
*/
#include "arch/sparc/faults.hh"
#include <algorithm>
#include "arch/sparc/isa_traits.hh"
#include "arch/sparc/process.hh"
#include "arch/sparc/tlb.hh"
#include "arch/sparc/types.hh"
#include "base/bitfield.hh"
#include "base/trace.hh"
#include "cpu/base.hh"
#include "cpu/thread_context.hh"
#include "mem/page_table.hh"
#include "sim/full_system.hh"
#include "sim/process.hh"
using namespace std;
namespace SparcISA
{
template<> SparcFaultBase::FaultVals
SparcFault<PowerOnReset>::vals
("power_on_reset", 0x001, 0, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<WatchDogReset>::vals
("watch_dog_reset", 0x002, 120, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<ExternallyInitiatedReset>::vals
("externally_initiated_reset", 0x003, 110, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<SoftwareInitiatedReset>::vals
("software_initiated_reset", 0x004, 130, {SH, SH, H});
template<> SparcFaultBase::FaultVals
SparcFault<REDStateException>::vals
("RED_state_exception", 0x005, 1, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<StoreError>::vals
("store_error", 0x007, 201, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<InstructionAccessException>::vals
("instruction_access_exception", 0x008, 300, {H, H, H});
//XXX This trap is apparently dropped from ua2005
/*template<> SparcFaultBase::FaultVals
SparcFault<InstructionAccessMMUMiss>::vals
{"inst_mmu", 0x009, 2, {H, H, H}};*/
template<> SparcFaultBase::FaultVals
SparcFault<InstructionAccessError>::vals
("instruction_access_error", 0x00A, 400, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<IllegalInstruction>::vals
("illegal_instruction", 0x010, 620, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<PrivilegedOpcode>::vals
("privileged_opcode", 0x011, 700, {P, SH, SH});
//XXX This trap is apparently dropped from ua2005
/*template<> SparcFaultBase::FaultVals
SparcFault<UnimplementedLDD>::vals
{"unimp_ldd", 0x012, 6, {H, H, H}};*/
//XXX This trap is apparently dropped from ua2005
/*template<> SparcFaultBase::FaultVals
SparcFault<UnimplementedSTD>::vals
{"unimp_std", 0x013, 6, {H, H, H}};*/
template<> SparcFaultBase::FaultVals
SparcFault<FpDisabled>::vals
("fp_disabled", 0x020, 800, {P, P, H});
/* SPARCv8 and SPARCv9 define just fp_disabled trap. SIMD is not contemplated
* as a separate part. Therefore, we use the same code and TT */
template<> SparcFaultBase::FaultVals
SparcFault<VecDisabled>::vals =
{"fp_disabled", 0x020, 800, {P, P, H}};
template<> SparcFaultBase::FaultVals
SparcFault<FpExceptionIEEE754>::vals
("fp_exception_ieee_754", 0x021, 1110, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<FpExceptionOther>::vals
("fp_exception_other", 0x022, 1110, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<TagOverflow>::vals
("tag_overflow", 0x023, 1400, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<CleanWindow>::vals
("clean_window", 0x024, 1010, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<DivisionByZero>::vals
("division_by_zero", 0x028, 1500, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<InternalProcessorError>::vals
("internal_processor_error", 0x029, 4, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<InstructionInvalidTSBEntry>::vals
("instruction_invalid_tsb_entry", 0x02A, 210, {H, H, SH});
template<> SparcFaultBase::FaultVals
SparcFault<DataInvalidTSBEntry>::vals
("data_invalid_tsb_entry", 0x02B, 1203, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<DataAccessException>::vals
("data_access_exception", 0x030, 1201, {H, H, H});
//XXX This trap is apparently dropped from ua2005
/*template<> SparcFaultBase::FaultVals
SparcFault<DataAccessMMUMiss>::vals
{"data_mmu", 0x031, 12, {H, H, H}};*/
template<> SparcFaultBase::FaultVals
SparcFault<DataAccessError>::vals
("data_access_error", 0x032, 1210, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<DataAccessProtection>::vals
("data_access_protection", 0x033, 1207, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<MemAddressNotAligned>::vals
("mem_address_not_aligned", 0x034, 1020, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<LDDFMemAddressNotAligned>::vals
("LDDF_mem_address_not_aligned", 0x035, 1010, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<STDFMemAddressNotAligned>::vals
("STDF_mem_address_not_aligned", 0x036, 1010, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<PrivilegedAction>::vals
("privileged_action", 0x037, 1110, {H, H, SH});
template<> SparcFaultBase::FaultVals
SparcFault<LDQFMemAddressNotAligned>::vals
("LDQF_mem_address_not_aligned", 0x038, 1010, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<STQFMemAddressNotAligned>::vals
("STQF_mem_address_not_aligned", 0x039, 1010, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<InstructionRealTranslationMiss>::vals
("instruction_real_translation_miss", 0x03E, 208, {H, H, SH});
template<> SparcFaultBase::FaultVals
SparcFault<DataRealTranslationMiss>::vals
("data_real_translation_miss", 0x03F, 1203, {H, H, H});
//XXX This trap is apparently dropped from ua2005
/*template<> SparcFaultBase::FaultVals
SparcFault<AsyncDataError>::vals
{"async_data", 0x040, 2, {H, H, H}};*/
template<> SparcFaultBase::FaultVals
SparcFault<InterruptLevelN>::vals
("interrupt_level_n", 0x040, 0, {P, P, SH});
template<> SparcFaultBase::FaultVals
SparcFault<HstickMatch>::vals
("hstick_match", 0x05E, 1601, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<TrapLevelZero>::vals
("trap_level_zero", 0x05F, 202, {H, H, SH});
template<> SparcFaultBase::FaultVals
SparcFault<InterruptVector>::vals
("interrupt_vector", 0x060, 2630, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<PAWatchpoint>::vals
("PA_watchpoint", 0x061, 1209, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<VAWatchpoint>::vals
("VA_watchpoint", 0x062, 1120, {P, P, SH});
template<> SparcFaultBase::FaultVals
SparcFault<FastInstructionAccessMMUMiss>::vals
("fast_instruction_access_MMU_miss", 0x064, 208, {H, H, SH});
template<> SparcFaultBase::FaultVals
SparcFault<FastDataAccessMMUMiss>::vals
("fast_data_access_MMU_miss", 0x068, 1203, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<FastDataAccessProtection>::vals
("fast_data_access_protection", 0x06C, 1207, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<InstructionBreakpoint>::vals
("instruction_break", 0x076, 610, {H, H, H});
template<> SparcFaultBase::FaultVals
SparcFault<CpuMondo>::vals
("cpu_mondo", 0x07C, 1608, {P, P, SH});
template<> SparcFaultBase::FaultVals
SparcFault<DevMondo>::vals
("dev_mondo", 0x07D, 1611, {P, P, SH});
template<> SparcFaultBase::FaultVals
SparcFault<ResumableError>::vals
("resume_error", 0x07E, 3330, {P, P, SH});
template<> SparcFaultBase::FaultVals
SparcFault<SpillNNormal>::vals
("spill_n_normal", 0x080, 900, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<SpillNOther>::vals
("spill_n_other", 0x0A0, 900, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<FillNNormal>::vals
("fill_n_normal", 0x0C0, 900, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<FillNOther>::vals
("fill_n_other", 0x0E0, 900, {P, P, H});
template<> SparcFaultBase::FaultVals
SparcFault<TrapInstruction>::vals
("trap_instruction", 0x100, 1602, {P, P, H});
/**
* 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?
HPSTATE hpstate= tc->readMiscRegNoEffect(MISCREG_HPSTATE);
hpstate.red = 1;
hpstate.hpriv = 1;
tc->setMiscReg(MISCREG_HPSTATE, hpstate);
// PSTATE.priv is set to 1 here. The manual says it should be 0, but
// Legion sets it to 1.
PSTATE pstate = tc->readMiscRegNoEffect(MISCREG_PSTATE);
pstate.priv = 1;
tc->setMiscReg(MISCREG_PSTATE, pstate);
}
/**
* 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->readMiscRegNoEffect(MISCREG_TL);
MiscReg TSTATE = tc->readMiscRegNoEffect(MISCREG_TSTATE);
PSTATE pstate = tc->readMiscRegNoEffect(MISCREG_PSTATE);
HPSTATE hpstate = tc->readMiscRegNoEffect(MISCREG_HPSTATE);
MiscReg CCR = tc->readIntReg(NumIntArchRegs + 2);
MiscReg ASI = tc->readMiscRegNoEffect(MISCREG_ASI);
MiscReg CWP = tc->readMiscRegNoEffect(MISCREG_CWP);
MiscReg CANSAVE = tc->readMiscRegNoEffect(NumIntArchRegs + 3);
MiscReg GL = tc->readMiscRegNoEffect(MISCREG_GL);
PCState pc = tc->pcState();
TL++;
Addr pcMask = pstate.am ? mask(32) : mask(64);
// 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->setMiscRegNoEffect(MISCREG_TSTATE, TSTATE);
// set TPC to PC
tc->setMiscRegNoEffect(MISCREG_TPC, pc.pc() & pcMask);
// set TNPC to NPC
tc->setMiscRegNoEffect(MISCREG_TNPC, pc.npc() & pcMask);
// set HTSTATE.hpstate to hpstate
tc->setMiscRegNoEffect(MISCREG_HTSTATE, hpstate);
// TT = trap type;
tc->setMiscRegNoEffect(MISCREG_TT, tt);
// Update GL
tc->setMiscReg(MISCREG_GL, min<int>(GL+1, MaxGL));
bool priv = pstate.priv; // just save the priv bit
pstate = 0;
pstate.priv = priv;
pstate.pef = 1;
tc->setMiscRegNoEffect(MISCREG_PSTATE, pstate);
hpstate.red = 1;
hpstate.hpriv = 1;
hpstate.ibe = 0;
hpstate.tlz = 0;
tc->setMiscRegNoEffect(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->setMiscReg(MISCREG_CWP, CWP);
}
}
/**
* This sets everything up for a normal trap except for actually jumping to
* the handler.
*/
void
doNormalFault(ThreadContext *tc, TrapType tt, bool gotoHpriv)
{
MiscReg TL = tc->readMiscRegNoEffect(MISCREG_TL);
MiscReg TSTATE = tc->readMiscRegNoEffect(MISCREG_TSTATE);
PSTATE pstate = tc->readMiscRegNoEffect(MISCREG_PSTATE);
HPSTATE hpstate = tc->readMiscRegNoEffect(MISCREG_HPSTATE);
MiscReg CCR = tc->readIntReg(NumIntArchRegs + 2);
MiscReg ASI = tc->readMiscRegNoEffect(MISCREG_ASI);
MiscReg CWP = tc->readMiscRegNoEffect(MISCREG_CWP);
MiscReg CANSAVE = tc->readIntReg(NumIntArchRegs + 3);
MiscReg GL = tc->readMiscRegNoEffect(MISCREG_GL);
PCState pc = tc->pcState();
// Increment the trap level
TL++;
tc->setMiscRegNoEffect(MISCREG_TL, TL);
Addr pcMask = pstate.am ? mask(32) : mask(64);
// Save off state
// 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->setMiscRegNoEffect(MISCREG_TSTATE, TSTATE);
// set TPC to PC
tc->setMiscRegNoEffect(MISCREG_TPC, pc.pc() & pcMask);
// set TNPC to NPC
tc->setMiscRegNoEffect(MISCREG_TNPC, pc.npc() & pcMask);
// set HTSTATE.hpstate to hpstate
tc->setMiscRegNoEffect(MISCREG_HTSTATE, hpstate);
// TT = trap type;
tc->setMiscRegNoEffect(MISCREG_TT, tt);
// Update the global register level
if (!gotoHpriv)
tc->setMiscReg(MISCREG_GL, min<int>(GL + 1, MaxPGL));
else
tc->setMiscReg(MISCREG_GL, min<int>(GL + 1, MaxGL));
// pstate.mm is unchanged
pstate.pef = 1; // PSTATE.pef = whether or not an fpu is present
pstate.am = 0;
pstate.ie = 0;
// pstate.tle is unchanged
// pstate.tct = 0
if (gotoHpriv) {
pstate.cle = 0;
// The manual says PSTATE.priv should be 0, but Legion leaves it alone
hpstate.red = 0;
hpstate.hpriv = 1;
hpstate.ibe = 0;
// hpstate.tlz is unchanged
tc->setMiscRegNoEffect(MISCREG_HPSTATE, hpstate);
} else { // we are going to priv
pstate.priv = 1;
pstate.cle = pstate.tle;
}
tc->setMiscRegNoEffect(MISCREG_PSTATE, pstate);
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->setMiscReg(MISCREG_CWP, CWP);
}
}
void
getREDVector(MiscReg TT, Addr &PC, Addr &NPC)
{
//XXX The following constant might belong in a header file.
const Addr RSTVAddr = 0xFFF0000000ULL;
PC = RSTVAddr | ((TT << 5) & 0xFF);
NPC = PC + sizeof(MachInst);
}
void
getHyperVector(ThreadContext * tc, Addr &PC, Addr &NPC, MiscReg TT)
{
Addr HTBA = tc->readMiscRegNoEffect(MISCREG_HTBA);
PC = (HTBA & ~mask(14)) | ((TT << 5) & mask(14));
NPC = PC + sizeof(MachInst);
}
void
getPrivVector(ThreadContext *tc, Addr &PC, Addr &NPC, MiscReg TT, MiscReg TL)
{
Addr TBA = tc->readMiscRegNoEffect(MISCREG_TBA);
PC = (TBA & ~mask(15)) |
(TL > 1 ? (1 << 14) : 0) |
((TT << 5) & mask(14));
NPC = PC + sizeof(MachInst);
}
void
SparcFaultBase::invoke(ThreadContext * tc, const StaticInstPtr &inst)
{
FaultBase::invoke(tc);
if (!FullSystem)
return;
countStat()++;
// 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->readMiscRegNoEffect(MISCREG_TL);
MiscReg tt = tc->readMiscRegNoEffect(MISCREG_TT);
PSTATE pstate = tc->readMiscRegNoEffect(MISCREG_PSTATE);
HPSTATE hpstate = tc->readMiscRegNoEffect(MISCREG_HPSTATE);
Addr PC, NPC;
PrivilegeLevel current;
if (hpstate.hpriv)
current = Hyperprivileged;
else if (pstate.priv)
current = Privileged;
else
current = User;
PrivilegeLevel level = getNextLevel(current);
if (hpstate.red || (tl == MaxTL - 1)) {
getREDVector(5, PC, NPC);
doREDFault(tc, tt);
// This changes the hpstate and pstate, so we need to make sure we
// save the old version on the trap stack in doREDFault.
enterREDState(tc);
} else if (tl == MaxTL) {
panic("Should go to error state here.. crap\n");
// 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(tc, PC, NPC, 2);
} else if (level == Hyperprivileged ||
(level == Privileged && trapType() >= 384)) {
doNormalFault(tc, trapType(), true);
getHyperVector(tc, PC, NPC, trapType());
} else {
doNormalFault(tc, trapType(), false);
getPrivVector(tc, PC, NPC, trapType(), tl + 1);
}
PCState pc;
pc.pc(PC);
pc.npc(NPC);
pc.nnpc(NPC + sizeof(MachInst));
pc.upc(0);
pc.nupc(1);
tc->pcState(pc);
}
void
PowerOnReset::invoke(ThreadContext *tc, const StaticInstPtr &inst)
{
// 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.
tc->setMiscRegNoEffect(MISCREG_TL, MaxTL);
tc->setMiscRegNoEffect(MISCREG_TT, trapType());
tc->setMiscReg(MISCREG_GL, MaxGL);
PSTATE pstate = 0;
pstate.pef = 1;
pstate.priv = 1;
tc->setMiscRegNoEffect(MISCREG_PSTATE, pstate);
// Turn on red and hpriv, set everything else to 0
HPSTATE hpstate = tc->readMiscRegNoEffect(MISCREG_HPSTATE);
hpstate.red = 1;
hpstate.hpriv = 1;
hpstate.ibe = 0;
hpstate.tlz = 0;
tc->setMiscRegNoEffect(MISCREG_HPSTATE, hpstate);
// The tick register is unreadable by nonprivileged software
tc->setMiscRegNoEffect(MISCREG_TICK, 1ULL << 63);
// Enter RED state. We do this last so that the actual state preserved in
// the trap stack is the state from before this fault.
enterREDState(tc);
Addr PC, NPC;
getREDVector(trapType(), PC, NPC);
PCState pc;
pc.pc(PC);
pc.npc(NPC);
pc.nnpc(NPC + sizeof(MachInst));
pc.upc(0);
pc.nupc(1);
tc->pcState(pc);
// These registers are specified as "undefined" after a POR, and they
// should have reasonable values after the miscregfile is reset
/*
// Clear all the soft interrupt bits
softint = 0;
// disable timer compare interrupts, reset tick_cmpr
tc->setMiscRegNoEffect(MISCREG_
tick_cmprFields.int_dis = 1;
tick_cmprFields.tick_cmpr = 0; // Reset to 0 for pretty printing
stickFields.npt = 1; // The TICK register is unreadable by by !priv
stick_cmprFields.int_dis = 1; // disable timer compare interrupts
stick_cmprFields.tick_cmpr = 0; // Reset to 0 for pretty printing
tt[tl] = _trapType;
hintp = 0; // no interrupts pending
hstick_cmprFields.int_dis = 1; // disable timer compare interrupts
hstick_cmprFields.tick_cmpr = 0; // Reset to 0 for pretty printing
*/
}
void
FastInstructionAccessMMUMiss::invoke(ThreadContext *tc,
const StaticInstPtr &inst)
{
if (FullSystem) {
SparcFaultBase::invoke(tc, inst);
return;
}
Process *p = tc->getProcessPtr();
const EmulationPageTable::Entry *pte = p->pTable->lookup(vaddr);
panic_if(!pte, "Tried to execute unmapped address %#x.\n", vaddr);
Addr alignedvaddr = p->pTable->pageAlign(vaddr);
// Grab fields used during instruction translation to figure out
// which context to use.
uint64_t tlbdata = tc->readMiscRegNoEffect(MISCREG_TLB_DATA);
// Inside a VM, a real address is the address that guest OS would
// interpret to be a physical address. To map to the physical address,
// it still needs to undergo a translation. The instruction
// translation code in the SPARC ITLB code assumes that the context is
// zero (kernel-level) if real addressing is being used.
bool is_real_address = !bits(tlbdata, 4);
// The SPARC ITLB code assumes that traps are executed in context
// zero so we carry that assumption through here.
bool trapped = bits(tlbdata, 18, 16) > 0;
// The primary context acts as a PASID. It allows the MMU to
// distinguish between virtual addresses that would alias to the
// same physical address (if two or more processes shared the same
// virtual address mapping).
int primary_context = bits(tlbdata, 47, 32);
// The partition id distinguishes between virtualized environments.
int const partition_id = 0;
// Given the assumptions in the translateInst code in the SPARC ITLB,
// the logic works out to the following for the context.
int context_id = (is_real_address || trapped) ? 0 : primary_context;
TlbEntry entry(p->pTable->pid(), alignedvaddr, pte->paddr,
pte->flags & EmulationPageTable::Uncacheable,
pte->flags & EmulationPageTable::ReadOnly);
// Insert the TLB entry.
// The entry specifying whether the address is "real" is set to
// false for syscall emulation mode regardless of whether the
// address is real in preceding code. Not sure sure that this is
// correct, but also not sure if it matters at all.
dynamic_cast<TLB *>(tc->getITBPtr())->
insert(alignedvaddr, partition_id, context_id, false, entry.pte);
}
void
FastDataAccessMMUMiss::invoke(ThreadContext *tc, const StaticInstPtr &inst)
{
if (FullSystem) {
SparcFaultBase::invoke(tc, inst);
return;
}
Process *p = tc->getProcessPtr();
const EmulationPageTable::Entry *pte = p->pTable->lookup(vaddr);
if (!pte && p->fixupStackFault(vaddr))
pte = p->pTable->lookup(vaddr);
panic_if(!pte, "Tried to access unmapped address %#x.\n", vaddr);
Addr alignedvaddr = p->pTable->pageAlign(vaddr);
// Grab fields used during data translation to figure out
// which context to use.
uint64_t tlbdata = tc->readMiscRegNoEffect(MISCREG_TLB_DATA);
// The primary context acts as a PASID. It allows the MMU to
// distinguish between virtual addresses that would alias to the
// same physical address (if two or more processes shared the same
// virtual address mapping). There's a secondary context used in the
// DTLB translation code, but it should __probably__ be zero for
// syscall emulation code. (The secondary context is used by Solaris
// to allow kernel privilege code to access user space code:
// [ISBN 0-13-022496-0]:PG199.)
int primary_context = bits(tlbdata, 47, 32);
// "Hyper-Privileged Mode" is in use. There are three main modes of
// operation for Sparc: Hyper-Privileged Mode, Privileged Mode, and
// User Mode.
int hpriv = bits(tlbdata, 0);
// Reset, Error and Debug state is in use. Something horrible has
// happened or the system is operating in Reset Mode.
int red = bits(tlbdata, 1);
// Inside a VM, a real address is the address that guest OS would
// interpret to be a physical address. To map to the physical address,
// it still needs to undergo a translation. The instruction
// translation code in the SPARC ITLB code assumes that the context is
// zero (kernel-level) if real addressing is being used.
int is_real_address = !bits(tlbdata, 5);
// Grab the address space identifier register from the thread context.
// XXX: Inspecting how setMiscReg and setMiscRegNoEffect behave for
// MISCREG_ASI causes me to think that the ASI register implementation
// might be bugged. The NoEffect variant changes the ASI register
// value in the architectural state while the normal variant changes
// the context field in the thread context's currently decoded request
// but does not directly affect the ASI register value in the
// architectural state. The ASI values and the context field in the
// request packet seem to have completely different uses.
MiscReg reg_asi = tc->readMiscRegNoEffect(MISCREG_ASI);
ASI asi = static_cast<ASI>(reg_asi);
// The SPARC DTLB code assumes that traps are executed in context
// zero if the asi value is ASI_IMPLICIT (which is 0x0). There's also
// an assumption that the nucleus address space is being used, but
// the context is the relevant issue since we need to pass it to TLB.
bool trapped = bits(tlbdata, 18, 16) > 0;
// Given the assumptions in the translateData code in the SPARC DTLB,
// the logic works out to the following for the context.
int context_id = ((!hpriv && !red && is_real_address) ||
asiIsReal(asi) ||
(trapped && asi == ASI_IMPLICIT))
? 0 : primary_context;
// The partition id distinguishes between virtualized environments.
int const partition_id = 0;
TlbEntry entry(p->pTable->pid(), alignedvaddr, pte->paddr,
pte->flags & EmulationPageTable::Uncacheable,
pte->flags & EmulationPageTable::ReadOnly);
// Insert the TLB entry.
// The entry specifying whether the address is "real" is set to
// false for syscall emulation mode regardless of whether the
// address is real in preceding code. Not sure sure that this is
// correct, but also not sure if it matters at all.
dynamic_cast<TLB *>(tc->getDTBPtr())->
insert(alignedvaddr, partition_id, context_id, false, entry.pte);
}
void
SpillNNormal::invoke(ThreadContext *tc, const StaticInstPtr &inst)
{
if (FullSystem) {
SparcFaultBase::invoke(tc, inst);
return;
}
doNormalFault(tc, trapType(), false);
Process *p = tc->getProcessPtr();
SparcProcess *sp = dynamic_cast<SparcProcess *>(p);
assert(sp);
// Then adjust the PC and NPC
tc->pcState(sp->readSpillStart());
}
void
FillNNormal::invoke(ThreadContext *tc, const StaticInstPtr &inst)
{
if (FullSystem) {
SparcFaultBase::invoke(tc, inst);
return;
}
doNormalFault(tc, trapType(), false);
Process *p = tc->getProcessPtr();
SparcProcess *sp = dynamic_cast<SparcProcess *>(p);
assert(sp);
// Then adjust the PC and NPC
tc->pcState(sp->readFillStart());
}
void
TrapInstruction::invoke(ThreadContext *tc, const StaticInstPtr &inst)
{
if (FullSystem) {
SparcFaultBase::invoke(tc, inst);
return;
}
// In SE, this mechanism is how the process requests a service from
// the operating system. We'll get the process object from the thread
// context and let it service the request.
Process *p = tc->getProcessPtr();
SparcProcess *sp = dynamic_cast<SparcProcess *>(p);
assert(sp);
Fault fault;
sp->handleTrap(_n, tc, &fault);
// We need to explicitly advance the pc, since that's not done for us
// on a faulting instruction
PCState pc = tc->pcState();
pc.advance();
tc->pcState(pc);
}
} // namespace SparcISA