/// <summary>
/// Parses the MADT
/// </summary>
/// <param name="madt">The MADT</param>
private static void parseMADT(MADT *madt)
{
m_madt = madt;
LocalApic.SetLocalControllerAddress(madt->LocalControllerAddress);
m_intSourceOverrides = new ISAOverride[16];
for (uint i = 0; i < 16; i++)
{
m_intSourceOverrides[i].GSI = i;
m_intSourceOverrides[i].Polarity = IOApic.IOAPIC_REDIR_POLARITY_HIGH;
m_intSourceOverrides[i].Trigger = IOApic.IOAPIC_REDIR_TRIGGER_EDGE;
}
// After the flags field, the rest of the table contains a variable length of records
uint current = (uint)madt + (uint)sizeof(MADT);
uint end = current + madt->Header.Length - (uint)sizeof(MADT);
while (current < end)
{
ApicEntryHeader * header = (ApicEntryHeader *)current;
ApicEntryHeaderType type = (ApicEntryHeaderType)header->Type;
switch (type)
{
case ApicEntryHeaderType.LOCAL_APIC:
ApicLocalApic *localAPIC = (ApicLocalApic *)(current + sizeof(ApicEntryHeader));
Console.Write("[ACPI] Found CPU ");
Console.WriteNum(localAPIC->ProcessorID);
Console.Write('\n');
break;
case ApicEntryHeaderType.IO_APIC:
ApicIOApic *IOApicStruct = (ApicIOApic *)(current + sizeof(ApicEntryHeader));
Console.Write("[ACPI] Found IO APIC at ");
Console.WriteHex(IOApicStruct->IOAPICAddress);
Console.Write('\n');
IOApic IOApic = new IOApic(IOApicStruct->IOAPIC_ID, (void *)IOApicStruct->IOAPICAddress, IOApicStruct->GlobalSystemInterruptBase);
IOApicManager.Add(IOApic);
break;
case ApicEntryHeaderType.INTERRUPT_SOURCE_OVERRIDE:
ApicInterruptSourceOverride *intSourceOverride = (ApicInterruptSourceOverride *)(current + sizeof(ApicEntryHeader));
m_intSourceOverrides[intSourceOverride->IRQSource].GSI = intSourceOverride->GlobalSystemInterrupt;
m_intSourceOverrides[intSourceOverride->IRQSource].Polarity = (uint)(intSourceOverride->Flags & 0x3);
m_intSourceOverrides[intSourceOverride->IRQSource].Trigger = (uint)((intSourceOverride->Flags >> 2) & 0x3);
break;
}
current += header->Length;
}
}
/// <summary>
/// IRQ handler
/// </summary>
/// <param name="regsPtr">Pointer to registers</param>
public static unsafe void Handler(Regs *regsPtr)
{
int irqNum = regsPtr->IntNum;
if (handlers[irqNum] != null)
{
// Loop through handlers to see who has sent interrupt
for (int i = 0; i < IRQ_MAX_SHARING; i++)
{
if (handlers[irqNum][i] == null || handlers[irqNum][i]())
{
break;
}
}
}
LocalApic.SendEOI();
}