public static void Break()
{
KernelMessage.Write("<BREAK>");
while (true)
{
Native.Nop();
}
}
public static void Setup()
{
KernelMessage.WriteLine("Setup IDT");
IDTAddr = PageFrameManager.AllocatePage(PageFrameRequestFlags.Default)->PhysicalAddress;
KernelMessage.WriteLine("Address of IDT: {0:X8}", IDTAddr);
// Setup IDT table
Mosa.Runtime.Internal.MemoryClear(new IntPtr((uint)IDTAddr), 6);
Intrinsic.Store16(new IntPtr((uint)IDTAddr), (Offset.TotalSize * 256) - 1);
Intrinsic.Store32(new IntPtr((uint)IDTAddr), 2, IDTAddr + 6);
KernelMessage.Write("Set IDT table entries...");
SetTableEntries();
KernelMessage.WriteLine("done");
handlers = new InterruptInfo[256];
for (var i = 0; i <= 255; i++)
{
var info = new InterruptInfo
{
Interrupt = i,
CountStatistcs = true,
Trace = true,
Handler = UndefinedHandler
};
if (i == (int)KnownInterrupt.ClockTimer)
{
info.Trace = false;
info.CountStatistcs = false;
}
handlers[i] = info;
}
SetInterruptHandler(KnownInterrupt.DivideError, InterruptsHandlers.DivideError);
SetInterruptHandler(KnownInterrupt.ArithmeticOverflowException, InterruptsHandlers.ArithmeticOverflowException);
SetInterruptHandler(KnownInterrupt.BoundCheckError, InterruptsHandlers.BoundCheckError);
SetInterruptHandler(KnownInterrupt.InvalidOpcode, InterruptsHandlers.InvalidOpcode);
SetInterruptHandler(KnownInterrupt.CoProcessorNotAvailable, InterruptsHandlers.CoProcessorNotAvailable);
SetInterruptHandler(KnownInterrupt.DoubleFault, InterruptsHandlers.DoubleFault);
SetInterruptHandler(KnownInterrupt.CoProcessorSegmentOverrun, InterruptsHandlers.CoProcessorSegmentOverrun);
SetInterruptHandler(KnownInterrupt.InvalidTSS, InterruptsHandlers.InvalidTSS);
SetInterruptHandler(KnownInterrupt.SegmentNotPresent, InterruptsHandlers.SegmentNotPresent);
SetInterruptHandler(KnownInterrupt.StackException, InterruptsHandlers.StackException);
SetInterruptHandler(KnownInterrupt.GeneralProtectionException, InterruptsHandlers.GeneralProtectionException);
SetInterruptHandler(KnownInterrupt.PageFault, InterruptsHandlers.PageFault);
SetInterruptHandler(KnownInterrupt.CoProcessorError, InterruptsHandlers.CoProcessorError);
SetInterruptHandler(KnownInterrupt.SIMDFloatinPointException, InterruptsHandlers.SIMDFloatinPointException);
SetInterruptHandler(KnownInterrupt.ClockTimer, InterruptsHandlers.ClockTimer);
KernelMessage.Write("Enabling interrupts...");
var idtAddr = (uint)IDTAddr;
Native.Lidt(idtAddr);
Native.Sti();
KernelMessage.WriteLine("done");
}
/// <summary>
/// Sets up the PageTable
/// </summary>
public static void Setup(Addr addrPageDirectory, Addr addrPageTable)
{
KernelMessage.WriteLine("Setup PageTable");
AddrPageDirectory = addrPageDirectory;
AddrPageTable = addrPageTable;
// Setup Page Directory
PageDirectoryEntry *pde = (PageDirectoryEntry *)AddrPageDirectory;
for (int index = 0; index < 1024; index++)
{
pde[index] = new PageDirectoryEntry();
pde[index].Present = true;
pde[index].Writable = true;
pde[index].User = true;
pde[index].PageTableEntry = (PageTableEntry *)(uint)(AddrPageTable + (index * 4096));
}
// Map the first 128MB of memory (32786 4K pages) (why 128MB?)
for (int index = 0; index < 1024 * 32; index++)
{
PageTableEntry *pte = (PageTableEntry *)AddrPageTable;
pte[index] = new PageTableEntry();
pte[index].Present = true;
pte[index].Writable = true;
pte[index].User = true;
pte[index].PhysicalAddress = (uint)(index * 4096);
}
// Unmap the first page for null pointer exceptions
MapVirtualAddressToPhysical(0x0, 0x0, false);
// Set CR3 register on processor - sets page directory
KernelMessage.WriteLine("Set CR3 to {0:X8}", PageTable.AddrPageDirectory);
Native.SetCR3(AddrPageDirectory);
KernelMessage.Write("Enable Paging... ");
// Set CR0.WP
Native.SetCR0(Native.GetCR0() | 0x10000);
// Set CR0 register on processor - turns on virtual memory
Native.SetCR0(Native.GetCR0() | 0x80000000);
KernelMessage.WriteLine("Done");
}
public static void DumpToConsole(uint addr, uint length)
{
var sb = new StringBuffer();
sb.Append("{0:X}+{1:D} ", addr, length);
KernelMessage.Write(sb);
sb.Clear();
for (uint a = addr; a < addr + length; a++)
{
sb.Clear();
if (a != addr)
{
sb.Append(" ");
}
var m = Native.Get8(a);
sb.Append(m, 16, 2);
KernelMessage.Write(sb);
}
}
/// <summary>
/// Sets up the GDT table and entries
/// </summary>
public static void Setup(Addr addr)
{
KernelMessage.Write("Setup GDT...");
gdtTableAddress = addr;
table = (DescriptorTable *)gdtTableAddress;
table->Clear();
table->AdressOfEntries = gdtTableAddress + DescriptorTable.StructSize;
//Null segment
var nullEntry = DescriptorTableEntry.CreateNullDescriptor();
table->AddEntry(nullEntry);
//code segment
var codeEntry = DescriptorTableEntry.CreateCode(0, 0xFFFFFFFF);
codeEntry.CodeSegment_Readable = true;
codeEntry.PriviligeRing = 0;
codeEntry.Present = true;
codeEntry.AddressMode = DescriptorTableEntry.EAddressMode.Bits32;
codeEntry.Granularity = true;
table->AddEntry(codeEntry);
//data segment
var dataEntry = DescriptorTableEntry.CreateData(0, 0xFFFFFFFF);
dataEntry.DataSegment_Writable = true;
dataEntry.PriviligeRing = 0;
dataEntry.Present = true;
dataEntry.AddressMode = DescriptorTableEntry.EAddressMode.Bits32;
dataEntry.Granularity = true;
table->AddEntry(dataEntry);
Flush();
KernelMessage.WriteLine("Done");
}
/// <summary>
/// Allocate a physical page from the free list
/// </summary>
/// <returns>The page</returns>
Page *Allocate(uint num)
{
KernelMessage.Write("Request {0} pages...", num);
var cnt = 0;
if (lastAllocatedPage == null)
{
lastAllocatedPage = PageArray;
}
Page *p = lastAllocatedPage->Next;
while (true)
{
if (p == null)
{
p = PageArray;
}
if (p->Status == PageStatus.Free)
{
var head = p;
// Found free Page. Check now free range.
for (var i = 0; i < num; i++)
{
if (p == null)
{
break; // Reached end. SorRange is incomplete
}
if (p->Status != PageStatus.Free) // Used -> so we can abort the searach
{
break;
}
if (i == num - 1)
{ // all loops successful. So we found our range.
head->Tail = p;
head->PagesUsed = num;
p = head;
for (var n = 0; n < num; n++)
{
p->Status = PageStatus.Used;
p->Head = head;
p->Tail = head->Tail;
p = p->Next;
PagesUsed++;
}
lastAllocatedPage = p;
KernelMessage.WriteLine("Allocated from {0:X8} to {1:X8}", (uint)head->PhysicalAddress, (uint)head->Tail->PhysicalAddress);
return(head);
}
p = p->Next;
}
}
if (p->Tail != null)
{
p = p->Tail;
}
p = p->Next;
if (++cnt > PageCount)
{
break;
}
}
Panic.Error("PageFrameAllocator: No free Page found");
return(null);
}
public static void DumpToConsoleLine(uint addr, uint length)
{
DumpToConsole(addr, length);
KernelMessage.Write('\n');
}