x86, mem: Don't try to force physical addresses on the system.

Use the system object to allocate physical memory instead of manually
placing certain structures and then forcing the system to start other
allocations after them in physical memory.

Change-Id: Ie18c81645c3b648c64a6d7a649a0e50f7028f344
Reviewed-on: https://gem5-review.googlesource.com/7346
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
diff --git a/src/arch/x86/process.cc b/src/arch/x86/process.cc
index 0a94ac4..43a5273 100644
--- a/src/arch/x86/process.cc
+++ b/src/arch/x86/process.cc
@@ -103,8 +103,7 @@
                               new ArchPageTable(
                                       params->name, params->pid,
                                       params->system, PageBytes,
-                                      PageTableLayout,
-                                      pageTablePhysAddr >> PageShift)) :
+                                      PageTableLayout)) :
                       new EmulationPageTable(params->name, params->pid,
                                              PageBytes),
               objFile),
@@ -214,12 +213,19 @@
     if (kvmInSE) {
         PortProxy physProxy = system->physProxy;
 
+        Addr syscallCodePhysAddr = system->allocPhysPages(1);
+        Addr gdtPhysAddr = system->allocPhysPages(1);
+        Addr idtPhysAddr = system->allocPhysPages(1);
+        Addr istPhysAddr = system->allocPhysPages(1);
+        Addr tssPhysAddr = system->allocPhysPages(1);
+        Addr pfHandlerPhysAddr = system->allocPhysPages(1);
+
         /*
          * Set up the gdt.
          */
         uint8_t numGDTEntries = 0;
         uint64_t nullDescriptor = 0;
-        physProxy.writeBlob(GDTPhysAddr + numGDTEntries * 8,
+        physProxy.writeBlob(gdtPhysAddr + numGDTEntries * 8,
                             (uint8_t *)(&nullDescriptor), 8);
         numGDTEntries++;
 
@@ -243,7 +249,7 @@
         csLowPLDesc.type.codeOrData = 1;
         csLowPLDesc.dpl = 0;
         uint64_t csLowPLDescVal = csLowPLDesc;
-        physProxy.writeBlob(GDTPhysAddr + numGDTEntries * 8,
+        physProxy.writeBlob(gdtPhysAddr + numGDTEntries * 8,
                             (uint8_t *)(&csLowPLDescVal), 8);
 
         numGDTEntries++;
@@ -257,7 +263,7 @@
         dsLowPLDesc.type.codeOrData = 0;
         dsLowPLDesc.dpl = 0;
         uint64_t dsLowPLDescVal = dsLowPLDesc;
-        physProxy.writeBlob(GDTPhysAddr + numGDTEntries * 8,
+        physProxy.writeBlob(gdtPhysAddr + numGDTEntries * 8,
                             (uint8_t *)(&dsLowPLDescVal), 8);
 
         numGDTEntries++;
@@ -271,7 +277,7 @@
         dsDesc.type.codeOrData = 0;
         dsDesc.dpl = 3;
         uint64_t dsDescVal = dsDesc;
-        physProxy.writeBlob(GDTPhysAddr + numGDTEntries * 8,
+        physProxy.writeBlob(gdtPhysAddr + numGDTEntries * 8,
                             (uint8_t *)(&dsDescVal), 8);
 
         numGDTEntries++;
@@ -285,7 +291,7 @@
         csDesc.type.codeOrData = 1;
         csDesc.dpl = 3;
         uint64_t csDescVal = csDesc;
-        physProxy.writeBlob(GDTPhysAddr + numGDTEntries * 8,
+        physProxy.writeBlob(gdtPhysAddr + numGDTEntries * 8,
                             (uint8_t *)(&csDescVal), 8);
 
         numGDTEntries++;
@@ -321,7 +327,7 @@
             uint64_t high;
         } tssDescVal = {TSSDescLow, TSSDescHigh};
 
-        physProxy.writeBlob(GDTPhysAddr + numGDTEntries * 8,
+        physProxy.writeBlob(gdtPhysAddr + numGDTEntries * 8,
                             (uint8_t *)(&tssDescVal), sizeof(tssDescVal));
 
         numGDTEntries++;
@@ -405,7 +411,7 @@
             CR0 cr2 = 0;
             tc->setMiscReg(MISCREG_CR2, cr2);
 
-            CR3 cr3 = pageTablePhysAddr;
+            CR3 cr3 = dynamic_cast<ArchPageTable *>(pTable)->basePtr();
             tc->setMiscReg(MISCREG_CR3, cr3);
 
             CR4 cr4 = 0;
@@ -428,10 +434,6 @@
             CR4 cr8 = 0;
             tc->setMiscReg(MISCREG_CR8, cr8);
 
-            const Addr PageMapLevel4 = pageTablePhysAddr;
-            //Point to the page tables.
-            tc->setMiscReg(MISCREG_CR3, PageMapLevel4);
-
             tc->setMiscReg(MISCREG_MXCSR, 0x1f80);
 
             tc->setMiscReg(MISCREG_APIC_BASE, 0xfee00900);
@@ -493,7 +495,7 @@
         tss.RSP1_high = tss.IST1_high;
         tss.RSP2_low  = tss.IST1_low;
         tss.RSP2_high = tss.IST1_high;
-        physProxy.writeBlob(TSSPhysAddr, (uint8_t *)(&tss), sizeof(tss));
+        physProxy.writeBlob(tssPhysAddr, (uint8_t *)(&tss), sizeof(tss));
 
         /* Setting IDT gates */
         GateDescriptorLow PFGateLow = 0;
@@ -513,7 +515,7 @@
             uint64_t high;
         } PFGate = {PFGateLow, PFGateHigh};
 
-        physProxy.writeBlob(IDTPhysAddr + 0xE0,
+        physProxy.writeBlob(idtPhysAddr + 0xE0,
                             (uint8_t *)(&PFGate), sizeof(PFGate));
 
         /* System call handler */
@@ -539,7 +541,7 @@
             0x48, 0xcf
         };
 
-        physProxy.writeBlob(PFHandlerPhysAddr, faultBlob, sizeof(faultBlob));
+        physProxy.writeBlob(pfHandlerPhysAddr, faultBlob, sizeof(faultBlob));
 
         MultiLevelPageTable<PageTableOps> *pt =
             dynamic_cast<MultiLevelPageTable<PageTableOps> *>(pTable);
@@ -547,15 +549,15 @@
         /* Syscall handler */
         pt->map(syscallCodeVirtAddr, syscallCodePhysAddr, PageBytes, false);
         /* GDT */
-        pt->map(GDTVirtAddr, GDTPhysAddr, PageBytes, false);
+        pt->map(GDTVirtAddr, gdtPhysAddr, PageBytes, false);
         /* IDT */
-        pt->map(IDTVirtAddr, IDTPhysAddr, PageBytes, false);
+        pt->map(IDTVirtAddr, idtPhysAddr, PageBytes, false);
         /* TSS */
-        pt->map(TSSVirtAddr, TSSPhysAddr, PageBytes, false);
+        pt->map(TSSVirtAddr, tssPhysAddr, PageBytes, false);
         /* IST */
-        pt->map(ISTVirtAddr, ISTPhysAddr, PageBytes, false);
+        pt->map(ISTVirtAddr, istPhysAddr, PageBytes, false);
         /* PF handler */
-        pt->map(PFHandlerVirtAddr, PFHandlerPhysAddr, PageBytes, false);
+        pt->map(PFHandlerVirtAddr, pfHandlerPhysAddr, PageBytes, false);
         /* MMIO region for m5ops */
         pt->map(MMIORegionVirtAddr, MMIORegionPhysAddr, 16*PageBytes, false);
     } else {
diff --git a/src/arch/x86/system.hh b/src/arch/x86/system.hh
index 45bc965..829a18d 100644
--- a/src/arch/x86/system.hh
+++ b/src/arch/x86/system.hh
@@ -64,21 +64,14 @@
 
     /* memory mappings for KVMCpu in SE mode */
     const uint64_t syscallCodeVirtAddr = 0xffff800000000000;
-    const uint64_t syscallCodePhysAddr = 0x60000;
     const uint64_t GDTVirtAddr = 0xffff800000001000;
-    const uint64_t GDTPhysAddr = 0x61000;
     const uint64_t IDTVirtAddr = 0xffff800000002000;
-    const uint64_t IDTPhysAddr = 0x62000;
     const uint64_t TSSVirtAddr = 0xffff800000003000;
     const uint64_t TSSPhysAddr = 0x63000;
     const uint64_t ISTVirtAddr = 0xffff800000004000;
-    const uint64_t ISTPhysAddr = 0x64000;
     const uint64_t PFHandlerVirtAddr = 0xffff800000005000;
-    const uint64_t PFHandlerPhysAddr = 0x65000;
     const uint64_t MMIORegionVirtAddr = 0xffffc90000000000;
     const uint64_t MMIORegionPhysAddr = 0xffff0000;
-
-    const uint64_t pageTablePhysAddr = 0x70000;
 }
 
 class X86System : public System
diff --git a/src/mem/multi_level_page_table.hh b/src/mem/multi_level_page_table.hh
index 7cbbd8c..30f5347 100644
--- a/src/mem/multi_level_page_table.hh
+++ b/src/mem/multi_level_page_table.hh
@@ -115,7 +115,7 @@
     /**
      * Physical address to the last level of the page table
      */
-    Addr basePtr;
+    Addr _basePtr;
 
     /**
      * Vector with sizes of all levels in base 2 logarithmic
@@ -140,12 +140,13 @@
 public:
     MultiLevelPageTable(const std::string &__name, uint64_t _pid,
                         System *_sys, Addr pageSize,
-                        const std::vector<uint8_t> &layout,
-                        Addr _basePtr);
+                        const std::vector<uint8_t> &layout);
     ~MultiLevelPageTable();
 
     void initState(ThreadContext* tc) override;
 
+    Addr basePtr() { return _basePtr; }
+
     void map(Addr vaddr, Addr paddr, int64_t size,
              uint64_t flags = 0) override;
     void remap(Addr vaddr, int64_t size, Addr new_vaddr) override;
diff --git a/src/mem/multi_level_page_table_impl.hh b/src/mem/multi_level_page_table_impl.hh
index 3356c9e..d756de6 100644
--- a/src/mem/multi_level_page_table_impl.hh
+++ b/src/mem/multi_level_page_table_impl.hh
@@ -47,9 +47,9 @@
 template <class ISAOps>
 MultiLevelPageTable<ISAOps>::MultiLevelPageTable(
         const std::string &__name, uint64_t _pid, System *_sys,
-        Addr pageSize, const std::vector<uint8_t> &layout, Addr _basePtr)
+        Addr pageSize, const std::vector<uint8_t> &layout)
     : EmulationPageTable(__name, _pid, pageSize), system(_sys),
-    basePtr(_basePtr), logLevelSize(layout), numLevels(logLevelSize.size())
+      logLevelSize(layout), numLevels(logLevelSize.size())
 {
 }
 
@@ -62,18 +62,16 @@
 void
 MultiLevelPageTable<ISAOps>::initState(ThreadContext* tc)
 {
-    system->pagePtr = basePtr;
-
     /* setting first level of the page table */
     uint64_t log_req_size = floorLog2(sizeof(PageTableEntry)) +
-                            logLevelSize[numLevels-1];
+                            logLevelSize[numLevels - 1];
     assert(log_req_size >= PageShift);
     uint64_t npages = 1 << (log_req_size - PageShift);
 
-    Addr paddr = system->allocPhysPages(npages);
+    Addr _basePtr = system->allocPhysPages(npages);
 
     PortProxy &p = system->physProxy;
-    p.memsetBlob(paddr, 0, npages << PageShift);
+    p.memsetBlob(_basePtr, 0, npages << PageShift);
 }
 
 
@@ -83,7 +81,7 @@
 {
     std::vector<uint64_t> offsets = pTableISAOps.getOffsets(vaddr);
 
-    Addr level_base = basePtr;
+    Addr level_base = _basePtr;
     for (int i = numLevels - 1; i > 0; i--) {
 
         Addr entry_addr = (level_base<<PageShift) +
@@ -221,7 +219,7 @@
      * which is serialized separately, we will serialize
      * just the base pointer
      */
-    paramOut(cp, "ptable.pointer", basePtr);
+    paramOut(cp, "ptable.pointer", _basePtr);
 }
 
 template <class ISAOps>
@@ -229,5 +227,5 @@
 MultiLevelPageTable<ISAOps>::unserialize(CheckpointIn &cp)
 {
     EmulationPageTable::unserialize(cp);
-    paramIn(cp, "ptable.pointer", basePtr);
+    paramIn(cp, "ptable.pointer", _basePtr);
 }