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authorAndreas Sandberg <andreas@sandberg.pp.se>2013-06-03 13:55:41 +0200
committerAndreas Sandberg <andreas@sandberg.pp.se>2013-06-03 13:55:41 +0200
commit7846f59d0dcb36c13e06a3ba8a4c461e646582b6 (patch)
tree32b0ebd81cabb265409ad09e42285d2615354bdb /src/arch/x86/tlb.cc
parent63dae287035c9670c0622eefc9a19e0dc05c299f (diff)
downloadgem5-7846f59d0dcb36c13e06a3ba8a4c461e646582b6.tar.xz
arch: Create a method to finalize physical addresses
in the TLB Some architectures (currently only x86) require some fixing-up of physical addresses after a normal address translation. This is usually to remap devices such as the APIC, but could be used for other memory mapped devices as well. When running the CPU in a using hardware virtualization, we still need to do these address fix-ups before inserting the request into the memory system. This patch moves this patch allows that code to be used by such CPUs without doing full address translations.
Diffstat (limited to 'src/arch/x86/tlb.cc')
-rw-r--r--src/arch/x86/tlb.cc61
1 files changed, 36 insertions, 25 deletions
diff --git a/src/arch/x86/tlb.cc b/src/arch/x86/tlb.cc
index 33de0129a..52cc3e0ee 100644
--- a/src/arch/x86/tlb.cc
+++ b/src/arch/x86/tlb.cc
@@ -226,6 +226,40 @@ TLB::translateInt(RequestPtr req, ThreadContext *tc)
}
Fault
+TLB::finalizePhysical(RequestPtr req, ThreadContext *tc, Mode mode) const
+{
+ Addr paddr = req->getPaddr();
+
+ // Check for an access to the local APIC
+ if (FullSystem) {
+ LocalApicBase localApicBase =
+ tc->readMiscRegNoEffect(MISCREG_APIC_BASE);
+ AddrRange apicRange(localApicBase.base * PageBytes,
+ (localApicBase.base + 1) * PageBytes - 1);
+
+ if (apicRange.contains(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 - apicRange.start()));
+ }
+ }
+
+ return NoFault;
+}
+
+Fault
TLB::translate(RequestPtr req, ThreadContext *tc, Translation *translation,
Mode mode, bool &delayedResponse, bool timing)
{
@@ -366,31 +400,8 @@ TLB::translate(RequestPtr req, ThreadContext *tc, Translation *translation,
DPRINTF(TLB, "Translated %#x -> %#x.\n", vaddr, vaddr);
req->setPaddr(vaddr);
}
- // Check for an access to the local APIC
- if (FullSystem) {
- 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));
- }
- }
- return NoFault;
+
+ return finalizePhysical(req, tc, mode);
}
Fault