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Change the physical memory logic, and also add misspeculation fix to

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tlb index calls that are called from ExecContext::readIpr

arch/alpha/ev5.cc:
    Fix misspeculation bugs for misspeculated IPR accesses

--HG--
extra : convert_revision : c9ffcf9ef8123dfcaee1606c05aee8ad60d893d7
This commit is contained in:
Andrew Schultz 2004-02-18 21:38:55 -05:00
parent 2d5ef88e1c
commit 12747d3084
3 changed files with 102 additions and 91 deletions
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185
arch/alpha/alpha_memory.cc
View file

@ -282,19 +282,6 @@ AlphaItb::translate(MemReqPtr &req) const
if (req->flags & PHYSICAL) {
req->paddr = req->vaddr;
} else if ((MCSR_SP(ipr[AlphaISA::IPR_MCSR]) & 2) &&
VA_SPACE(req->vaddr) == 2) {
// Check for "superpage" mapping: when SP<1> is set, and
// VA<42:41> == 2, VA<39:13> maps directly to PA<39:13>.
// only valid in kernel mode
if (ICM_CM(ipr[AlphaISA::IPR_ICM]) != AlphaISA::mode_kernel) {
fault(req->vaddr, req->xc);
acv++;
return Itb_Acv_Fault;
}
req->paddr = req->vaddr & PA_IMPL_MASK;
} else {
// verify that this is a good virtual address
if (!validVirtualAddress(req->vaddr)) {
@ -303,24 +290,41 @@ AlphaItb::translate(MemReqPtr &req) const
return Itb_Acv_Fault;
}
// not a physical address: need to look up pte
AlphaISA::PTE *pte = lookup(VA_VPN(req->vaddr),
DTB_ASN_ASN(ipr[AlphaISA::IPR_DTB_ASN]));
// Check for "superpage" mapping: when SP<1> is set, and
// VA<42:41> == 2, VA<39:13> maps directly to PA<39:13>.
if ((MCSR_SP(ipr[AlphaISA::IPR_MCSR]) & 2) &&
VA_SPACE(req->vaddr) == 2) {
if (!pte) {
fault(req->vaddr, req->xc);
misses++;
return Itb_Fault_Fault;
}
// only valid in kernel mode
if (ICM_CM(ipr[AlphaISA::IPR_ICM]) != AlphaISA::mode_kernel) {
fault(req->vaddr, req->xc);
acv++;
return Itb_Acv_Fault;
}
req->paddr = PA_PFN2PA(pte->ppn) + VA_POFS(req->vaddr & ~3);
req->paddr = req->vaddr & PA_IMPL_MASK;
} else {
// not a physical address: need to look up pte
AlphaISA::PTE *pte = lookup(VA_VPN(req->vaddr),
DTB_ASN_ASN(ipr[AlphaISA::IPR_DTB_ASN]));
// check permissions for this access
if (!(pte->xre & (1 << ICM_CM(ipr[AlphaISA::IPR_ICM])))) {
// instruction access fault
fault(req->vaddr, req->xc);
acv++;
return Itb_Acv_Fault;
if (!pte) {
fault(req->vaddr, req->xc);
misses++;
return Itb_Fault_Fault;
}
req->paddr = PA_PFN2PA(pte->ppn) + VA_POFS(req->vaddr & ~3);
// check permissions for this access
if (!(pte->xre & (1 << ICM_CM(ipr[AlphaISA::IPR_ICM])))) {
// instruction access fault
fault(req->vaddr, req->xc);
acv++;
return Itb_Acv_Fault;
}
hits++;
}
}
@ -330,7 +334,6 @@ AlphaItb::translate(MemReqPtr &req) const
checkCacheability(req);
hits++;
return No_Fault;
}
@ -453,27 +456,7 @@ AlphaDtb::translate(MemReqPtr &req, bool write) const
if (req->flags & PHYSICAL) {
req->paddr = req->vaddr;
} else if ((MCSR_SP(ipr[AlphaISA::IPR_MCSR]) & 2) &&
VA_SPACE(req->vaddr) == 2) {
// Check for "superpage" mapping: when SP<1> is set, and
// VA<42:41> == 2, VA<39:13> maps directly to PA<39:13>.
// only valid in kernel mode
if (DTB_CM_CM(ipr[AlphaISA::IPR_DTB_CM]) != AlphaISA::mode_kernel) {
fault(req->vaddr,
((write ? MM_STAT_WR_MASK : 0) | MM_STAT_ACV_MASK),
req->xc);
if (write) { write_acv++; } else { read_acv++; }
return Dtb_Acv_Fault;
}
req->paddr = req->vaddr & PA_IMPL_MASK;
} else {
if (write)
write_accesses++;
else
read_accesses++;
// verify that this is a good virtual address
if (!validVirtualAddress(req->vaddr)) {
fault(req->vaddr,
@ -485,48 +468,72 @@ AlphaDtb::translate(MemReqPtr &req, bool write) const
return Dtb_Fault_Fault;
}
// not a physical address: need to look up pte
AlphaISA::PTE *pte = lookup(VA_VPN(req->vaddr),
DTB_ASN_ASN(ipr[AlphaISA::IPR_DTB_ASN]));
// Check for "superpage" mapping: when SP<1> is set, and
// VA<42:41> == 2, VA<39:13> maps directly to PA<39:13>.
if ((MCSR_SP(ipr[AlphaISA::IPR_MCSR]) & 2) &&
VA_SPACE(req->vaddr) == 2) {
if (!pte) {
// page fault
fault(req->vaddr,
((write ? MM_STAT_WR_MASK : 0) | MM_STAT_DTB_MISS_MASK),
req->xc);
if (write) { write_misses++; } else { read_misses++; }
return (req->flags & VPTE) ? Pdtb_Miss_Fault : Ndtb_Miss_Fault;
}
req->paddr = PA_PFN2PA(pte->ppn) | VA_POFS(req->vaddr);
if (write) {
if (!(pte->xwe & MODE2MASK(mode))) {
// declare the instruction access fault
fault(req->vaddr, MM_STAT_WR_MASK | MM_STAT_ACV_MASK |
(pte->fonw ? MM_STAT_FONW_MASK : 0),
req->xc);
write_acv++;
return Dtb_Fault_Fault;
}
if (pte->fonw) {
fault(req->vaddr, MM_STAT_WR_MASK | MM_STAT_FONW_MASK,
req->xc);
write_acv++;
return Dtb_Fault_Fault;
}
} else {
if (!(pte->xre & MODE2MASK(mode))) {
// only valid in kernel mode
if (DTB_CM_CM(ipr[AlphaISA::IPR_DTB_CM]) !=
AlphaISA::mode_kernel) {
fault(req->vaddr,
MM_STAT_ACV_MASK | (pte->fonr ? MM_STAT_FONR_MASK : 0),
((write ? MM_STAT_WR_MASK : 0) | MM_STAT_ACV_MASK),
req->xc);
read_acv++;
if (write) { write_acv++; } else { read_acv++; }
return Dtb_Acv_Fault;
}
if (pte->fonr) {
fault(req->vaddr, MM_STAT_FONR_MASK, req->xc);
read_acv++;
return Dtb_Fault_Fault;
req->paddr = req->vaddr & PA_IMPL_MASK;
} else {
if (write)
write_accesses++;
else
read_accesses++;
// not a physical address: need to look up pte
AlphaISA::PTE *pte = lookup(VA_VPN(req->vaddr),
DTB_ASN_ASN(ipr[AlphaISA::IPR_DTB_ASN]));
if (!pte) {
// page fault
fault(req->vaddr,
((write ? MM_STAT_WR_MASK : 0) | MM_STAT_DTB_MISS_MASK),
req->xc);
if (write) { write_misses++; } else { read_misses++; }
return (req->flags & VPTE) ? Pdtb_Miss_Fault : Ndtb_Miss_Fault;
}
req->paddr = PA_PFN2PA(pte->ppn) | VA_POFS(req->vaddr);
if (write) {
if (!(pte->xwe & MODE2MASK(mode))) {
// declare the instruction access fault
fault(req->vaddr, MM_STAT_WR_MASK | MM_STAT_ACV_MASK |
(pte->fonw ? MM_STAT_FONW_MASK : 0),
req->xc);
write_acv++;
return Dtb_Fault_Fault;
}
if (pte->fonw) {
fault(req->vaddr, MM_STAT_WR_MASK | MM_STAT_FONW_MASK,
req->xc);
write_acv++;
return Dtb_Fault_Fault;
}
} else {
if (!(pte->xre & MODE2MASK(mode))) {
fault(req->vaddr,
MM_STAT_ACV_MASK |
(pte->fonr ? MM_STAT_FONR_MASK : 0),
req->xc);
read_acv++;
return Dtb_Acv_Fault;
}
if (pte->fonr) {
fault(req->vaddr, MM_STAT_FONR_MASK, req->xc);
read_acv++;
return Dtb_Fault_Fault;
}
}
}
@ -546,10 +553,12 @@ AlphaDtb::translate(MemReqPtr &req, bool write) const
}
AlphaISA::PTE &
AlphaTlb::index()
AlphaTlb::index(bool advance)
{
AlphaISA::PTE *pte = &table[nlu];
nextnlu();
if (advance)
nextnlu();
return *pte;
}

2
arch/alpha/alpha_memory.hh
View file

@ -56,7 +56,7 @@ class AlphaTlb : public SimObject
int getsize() const { return size; }
AlphaISA::PTE &index();
AlphaISA::PTE &index(bool advance = true);
void insert(Addr vaddr, AlphaISA::PTE &pte);
void flushAll();

6
arch/alpha/ev5.cc
View file

@ -240,7 +240,9 @@ ExecContext::readIpr(int idx, Fault &fault)
case AlphaISA::IPR_VA:
// SFX: unlocks interrupt status registers
retval = ipr[idx];
regs.intrlock = false;
if (!misspeculating())
regs.intrlock = false;
break;
case AlphaISA::IPR_VA_FORM:
@ -253,7 +255,7 @@ ExecContext::readIpr(int idx, Fault &fault)
case AlphaISA::IPR_DTB_PTE:
{
AlphaISA::PTE &pte = dtb->index();
AlphaISA::PTE &pte = dtb->index(!misspeculating());
retval |= ((u_int64_t)pte.ppn & ULL(0x7ffffff)) << 32;
retval |= ((u_int64_t)pte.xre & ULL(0xf)) << 8;