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/*
* Copyright (c) 2007-2008 The Hewlett-Packard Development Company
* All rights reserved.
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* 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
*/
#include <cstring>
#include "arch/x86/insts/microldstop.hh"
#include "arch/x86/regs/misc.hh"
#include "arch/x86/regs/msr.hh"
#include "arch/x86/faults.hh"
#include "arch/x86/pagetable.hh"
#include "arch/x86/pagetable_walker.hh"
#include "arch/x86/tlb.hh"
#include "arch/x86/x86_traits.hh"
#include "base/bitfield.hh"
#include "base/trace.hh"
#include "config/full_system.hh"
#include "cpu/base.hh"
#include "cpu/thread_context.hh"
#include "debug/TLB.hh"
#include "mem/packet_access.hh"
#include "mem/request.hh"
#if !FULL_SYSTEM
#include "mem/page_table.hh"
#include "sim/process.hh"
#endif
#include "sim/full_system.hh"
namespace X86ISA {
TLB::TLB(const Params *p) : BaseTLB(p), configAddress(0), size(p->size)
{
tlb = new TlbEntry[size];
std::memset(tlb, 0, sizeof(TlbEntry) * size);
for (int x = 0; x < size; x++)
freeList.push_back(&tlb[x]);
walker = p->walker;
walker->setTLB(this);
}
TlbEntry *
TLB::insert(Addr vpn, TlbEntry &entry)
{
//TODO Deal with conflicting entries
TlbEntry *newEntry = NULL;
if (!freeList.empty()) {
newEntry = freeList.front();
freeList.pop_front();
} else {
newEntry = entryList.back();
entryList.pop_back();
}
*newEntry = entry;
newEntry->vaddr = vpn;
entryList.push_front(newEntry);
return newEntry;
}
TLB::EntryList::iterator
TLB::lookupIt(Addr va, bool update_lru)
{
//TODO make this smarter at some point
EntryList::iterator entry;
for (entry = entryList.begin(); entry != entryList.end(); entry++) {
if ((*entry)->vaddr <= va && (*entry)->vaddr + (*entry)->size > va) {
DPRINTF(TLB, "Matched vaddr %#x to entry starting at %#x "
"with size %#x.\n", va, (*entry)->vaddr, (*entry)->size);
if (update_lru) {
entryList.push_front(*entry);
entryList.erase(entry);
entry = entryList.begin();
}
break;
}
}
return entry;
}
TlbEntry *
TLB::lookup(Addr va, bool update_lru)
{
EntryList::iterator entry = lookupIt(va, update_lru);
if (entry == entryList.end())
return NULL;
else
return *entry;
}
void
TLB::invalidateAll()
{
DPRINTF(TLB, "Invalidating all entries.\n");
while (!entryList.empty()) {
TlbEntry *entry = entryList.front();
entryList.pop_front();
freeList.push_back(entry);
}
}
void
TLB::setConfigAddress(uint32_t addr)
{
configAddress = addr;
}
void
TLB::invalidateNonGlobal()
{
DPRINTF(TLB, "Invalidating all non global entries.\n");
EntryList::iterator entryIt;
for (entryIt = entryList.begin(); entryIt != entryList.end();) {
if (!(*entryIt)->global) {
freeList.push_back(*entryIt);
entryList.erase(entryIt++);
} else {
entryIt++;
}
}
}
void
TLB::demapPage(Addr va, uint64_t asn)
{
EntryList::iterator entry = lookupIt(va, false);
if (entry != entryList.end()) {
freeList.push_back(*entry);
entryList.erase(entry);
}
}
Fault
TLB::translateInt(RequestPtr req, ThreadContext *tc)
{
DPRINTF(TLB, "Addresses references internal memory.\n");
Addr vaddr = req->getVaddr();
Addr prefix = (vaddr >> 3) & IntAddrPrefixMask;
if (prefix == IntAddrPrefixCPUID) {
panic("CPUID memory space not yet implemented!\n");
} else if (prefix == IntAddrPrefixMSR) {
vaddr = (vaddr >> 3) & ~IntAddrPrefixMask;
req->setFlags(Request::MMAPPED_IPR);
MiscRegIndex regNum;
if (!msrAddrToIndex(regNum, vaddr))
return new GeneralProtection(0);
//The index is multiplied by the size of a MiscReg so that
//any memory dependence calculations will not see these as
//overlapping.
req->setPaddr((Addr)regNum * sizeof(MiscReg));
return NoFault;
} else if (prefix == IntAddrPrefixIO) {
// TODO If CPL > IOPL or in virtual mode, check the I/O permission
// bitmap in the TSS.
Addr IOPort = vaddr & ~IntAddrPrefixMask;
// Make sure the address fits in the expected 16 bit IO address
// space.
assert(!(IOPort & ~0xFFFF));
if (IOPort == 0xCF8 && req->getSize() == 4) {
req->setFlags(Request::MMAPPED_IPR);
req->setPaddr(MISCREG_PCI_CONFIG_ADDRESS * sizeof(MiscReg));
} else if ((IOPort & ~mask(2)) == 0xCFC) {
req->setFlags(Request::UNCACHEABLE);
Addr configAddress =
tc->readMiscRegNoEffect(MISCREG_PCI_CONFIG_ADDRESS);
if (bits(configAddress, 31, 31)) {
req->setPaddr(PhysAddrPrefixPciConfig |
mbits(configAddress, 30, 2) |
(IOPort & mask(2)));
} else {
req->setPaddr(PhysAddrPrefixIO | IOPort);
}
} else {
req->setFlags(Request::UNCACHEABLE);
req->setPaddr(PhysAddrPrefixIO | IOPort);
}
return NoFault;
} else {
panic("Access to unrecognized internal address space %#x.\n",
prefix);
}
}
Fault
TLB::translate(RequestPtr req, ThreadContext *tc, Translation *translation,
Mode mode, bool &delayedResponse, bool timing)
{
uint32_t flags = req->getFlags();
int seg = flags & SegmentFlagMask;
bool storeCheck = flags & (StoreCheck << FlagShift);
delayedResponse = false;
// If this is true, we're dealing with a request to a non-memory address
// space.
if (seg == SEGMENT_REG_MS) {
return translateInt(req, tc);
}
Addr vaddr = req->getVaddr();
DPRINTF(TLB, "Translating vaddr %#x.\n", vaddr);
HandyM5Reg m5Reg = tc->readMiscRegNoEffect(MISCREG_M5_REG);
// If protected mode has been enabled...
if (m5Reg.prot) {
DPRINTF(TLB, "In protected mode.\n");
// If we're not in 64-bit mode, do protection/limit checks
if (m5Reg.mode != LongMode) {
DPRINTF(TLB, "Not in long mode. Checking segment protection.\n");
// Check for a NULL segment selector.
if (!(seg == SEGMENT_REG_TSG || seg == SYS_SEGMENT_REG_IDTR ||
seg == SEGMENT_REG_HS || seg == SEGMENT_REG_LS)
&& !tc->readMiscRegNoEffect(MISCREG_SEG_SEL(seg)))
return new GeneralProtection(0);
bool expandDown = false;
SegAttr attr = tc->readMiscRegNoEffect(MISCREG_SEG_ATTR(seg));
if (seg >= SEGMENT_REG_ES && seg <= SEGMENT_REG_HS) {
if (!attr.writable && (mode == Write || storeCheck))
return new GeneralProtection(0);
if (!attr.readable && mode == Read)
return new GeneralProtection(0);
expandDown = attr.expandDown;
}
Addr base = tc->readMiscRegNoEffect(MISCREG_SEG_BASE(seg));
Addr limit = tc->readMiscRegNoEffect(MISCREG_SEG_LIMIT(seg));
// This assumes we're not in 64 bit mode. If we were, the default
// address size is 64 bits, overridable to 32.
int size = 32;
bool sizeOverride = (flags & (AddrSizeFlagBit << FlagShift));
SegAttr csAttr = tc->readMiscRegNoEffect(MISCREG_CS_ATTR);
if ((csAttr.defaultSize && sizeOverride) ||
(!csAttr.defaultSize && !sizeOverride))
size = 16;
Addr offset = bits(vaddr - base, size-1, 0);
Addr endOffset = offset + req->getSize() - 1;
if (expandDown) {
DPRINTF(TLB, "Checking an expand down segment.\n");
warn_once("Expand down segments are untested.\n");
if (offset <= limit || endOffset <= limit)
return new GeneralProtection(0);
} else {
if (offset > limit || endOffset > limit)
return new GeneralProtection(0);
}
}
// If paging is enabled, do the translation.
if (m5Reg.paging) {
DPRINTF(TLB, "Paging enabled.\n");
// The vaddr already has the segment base applied.
TlbEntry *entry = lookup(vaddr);
if (!entry) {
if (FullSystem) {
Fault fault = walker->start(tc, translation, req, mode);
if (timing || fault != NoFault) {
// This gets ignored in atomic mode.
delayedResponse = true;
return fault;
}
entry = lookup(vaddr);
assert(entry);
} else {
#if !FULL_SYSTEM
DPRINTF(TLB, "Handling a TLB miss for "
"address %#x at pc %#x.\n",
vaddr, tc->instAddr());
Process *p = tc->getProcessPtr();
TlbEntry newEntry;
bool success = p->pTable->lookup(vaddr, newEntry);
if (!success && mode != Execute) {
// Check if we just need to grow the stack.
if (p->fixupStackFault(vaddr)) {
// If we did, lookup the entry for the new page.
success = p->pTable->lookup(vaddr, newEntry);
}
}
if (!success) {
return new PageFault(vaddr, true, mode, true, false);
} else {
Addr alignedVaddr = p->pTable->pageAlign(vaddr);
DPRINTF(TLB, "Mapping %#x to %#x\n", alignedVaddr,
newEntry.pageStart());
entry = insert(alignedVaddr, newEntry);
}
DPRINTF(TLB, "Miss was serviced.\n");
#endif
}
}
// Do paging protection checks.
bool inUser = (m5Reg.cpl == 3 &&
!(flags & (CPL0FlagBit << FlagShift)));
CR0 cr0 = tc->readMiscRegNoEffect(MISCREG_CR0);
bool badWrite = (!entry->writable && (inUser || cr0.wp));
if ((inUser && !entry->user) || (mode == Write && badWrite)) {
// The page must have been present to get into the TLB in
// the first place. We'll assume the reserved bits are
// fine even though we're not checking them.
return new PageFault(vaddr, true, mode, inUser, false);
}
if (storeCheck && badWrite) {
// This would fault if this were a write, so return a page
// fault that reflects that happening.
return new PageFault(vaddr, true, Write, inUser, false);
}
DPRINTF(TLB, "Entry found with paddr %#x, "
"doing protection checks.\n", entry->paddr);
Addr paddr = entry->paddr | (vaddr & (entry->size-1));
DPRINTF(TLB, "Translated %#x -> %#x.\n", vaddr, paddr);
req->setPaddr(paddr);
if (entry->uncacheable)
req->setFlags(Request::UNCACHEABLE);
} else {
//Use the address which already has segmentation applied.
DPRINTF(TLB, "Paging disabled.\n");
DPRINTF(TLB, "Translated %#x -> %#x.\n", vaddr, vaddr);
req->setPaddr(vaddr);
}
} else {
// Real mode
DPRINTF(TLB, "In real mode.\n");
DPRINTF(TLB, "Translated %#x -> %#x.\n", vaddr, vaddr);
req->setPaddr(vaddr);
}
// Check for an access to the local APIC
#if FULL_SYSTEM
LocalApicBase localApicBase = tc->readMiscRegNoEffect(MISCREG_APIC_BASE);
Addr baseAddr = localApicBase.base * PageBytes;
Addr paddr = req->getPaddr();
if (baseAddr <= paddr && baseAddr + PageBytes > paddr) {
// The Intel developer's manuals say the below restrictions apply,
// but the linux kernel, because of a compiler optimization, breaks
// them.
/*
// Check alignment
if (paddr & ((32/8) - 1))
return new GeneralProtection(0);
// Check access size
if (req->getSize() != (32/8))
return new GeneralProtection(0);
*/
// Force the access to be uncacheable.
req->setFlags(Request::UNCACHEABLE);
req->setPaddr(x86LocalAPICAddress(tc->contextId(), paddr - baseAddr));
}
#endif
return NoFault;
};
Fault
TLB::translateAtomic(RequestPtr req, ThreadContext *tc, Mode mode)
{
bool delayedResponse;
return TLB::translate(req, tc, NULL, mode, delayedResponse, false);
}
void
TLB::translateTiming(RequestPtr req, ThreadContext *tc,
Translation *translation, Mode mode)
{
bool delayedResponse;
assert(translation);
Fault fault =
TLB::translate(req, tc, translation, mode, delayedResponse, true);
if (!delayedResponse)
translation->finish(fault, req, tc, mode);
}
#if FULL_SYSTEM
Tick
TLB::doMmuRegRead(ThreadContext *tc, Packet *pkt)
{
return tc->getCpuPtr()->ticks(1);
}
Tick
TLB::doMmuRegWrite(ThreadContext *tc, Packet *pkt)
{
return tc->getCpuPtr()->ticks(1);
}
Walker *
TLB::getWalker()
{
return walker;
}
#endif
void
TLB::serialize(std::ostream &os)
{
}
void
TLB::unserialize(Checkpoint *cp, const std::string §ion)
{
}
} // namespace X86ISA
X86ISA::TLB *
X86TLBParams::create()
{
return new X86ISA::TLB(this);
}
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