/*
 * GeekOS C code entry point
 * Copyright (c) 2001,2003,2004 David H. Hovemeyer <daveho@cs.umd.edu>
 * Copyright (c) 2003, Jeffrey K. Hollingsworth <hollings@cs.umd.edu>
 * Copyright (c) 2004, Iulian Neamtiu <neamtiu@cs.umd.edu>
 * $Revision: 1.10 $
 * 
 * This is free software.  You are permitted to use,
 * redistribute, and modify it as specified in the file "COPYING".
 */

#include <geekos/bootinfo.h>
#include <geekos/string.h>
#include <geekos/screen.h>
#include <geekos/mem.h>
#include <geekos/crc32.h>
#include <geekos/tss.h>
#include <geekos/int.h>
#include <geekos/kthread.h>
#include <geekos/trap.h>
#include <geekos/timer.h>
#include <geekos/keyboard.h>
#include <geekos/io.h>
#include <geekos/serial.h>
#include <geekos/reboot.h>
#include <geekos/mem.h>
#include <geekos/paging.h>
#include <geekos/ide.h>

#include <geekos/vmm.h>

#include <geekos/gdt.h>

#include <geekos/vmm_sizes.h>

/*
  static inline unsigned int cpuid_ecx(unsigned int op)
  {
  unsigned int eax, ecx;
  
  __asm__("cpuid"
  : "=a" (eax), "=c" (ecx)
  : "0" (op)
  : "bx", "dx" );
  
  return ecx;
  }
*/



extern void Get_MSR(ulong_t msr, unsigned int *val1, unsigned int *val2);
extern void Set_MSR(ulong_t msr, ulong_t val1, ulong_t val2);
extern uint_t Get_EIP();
extern uint_t Get_ESP();
extern uint_t Get_EBP();


int foo=42;

#define SPEAKER_PORT 0x61


void Buzz(unsigned delay, unsigned num)
{
  volatile int x;
  int i,j;
  unsigned char init;
  
  init=In_Byte(SPEAKER_PORT);

  for (i=0;i<num;i++) { 
    Out_Byte(SPEAKER_PORT, init|0x2);
    for (j=0;j<delay;j++) { 
      x+=j;
    }
    Out_Byte(SPEAKER_PORT, init);
    for (j=0;j<delay;j++) { 
      x+=j;
    }
  }
}

inline void MyOut_Byte(ushort_t port, uchar_t value)
{
    __asm__ __volatile__ (
	"outb %b0, %w1"
	:
	: "a" (value), "Nd" (port)
    );
}

/*
 * Read a byte from an I/O port.
 */
inline uchar_t MyIn_Byte(ushort_t port)
{
    uchar_t value;

    __asm__ __volatile__ (
	"inb %w1, %b0"
	: "=a" (value)
	: "Nd" (port)
    );

    return value;
}


extern void MyBuzzVM();

#define MYBUZZVM_START MyBuzzVM
#define MYBUZZVM_LEN   0x3d

void BuzzVM()
{
  int x;
  int j;
  unsigned char init;
  
  
  init=MyIn_Byte(SPEAKER_PORT);

  while (1) {
    MyOut_Byte(SPEAKER_PORT, init|0x2);
    for (j=0;j<1000000;j++) { 
      x+=j;
    }
    MyOut_Byte(SPEAKER_PORT, init);
    for (j=0;j<1000000;j++) { 
      x+=j;
    }
  }
}

extern void RunVM();

int vmRunning = 0;

void RunVM() {
  vmRunning = 1;

  while(1);
}




extern uint_t VMCS_STORE();
extern uint_t VMCS_READ();



void Buzzer(ulong_t arg) {
  ulong_t *doIBuzz = (ulong_t*)arg;
  while (1) {
    // Quick and dirty hack to save my hearing...
    // I'm not too worried about timing, so I'll deal with concurrency later...
    if (*doIBuzz == 1) {
      Buzz(1000000, 10);
    }
  }

}



void Hello(ulong_t arg)
{
  char *b="hello ";
  char byte;
  short port=0xe9;
  int i;
  while(1){
    for (i=0;i<6;i++) { 
      byte=b[i];
      __asm__ __volatile__ ("outb %b0, %w1" : : "a"(byte), "Nd"(port) );
    }
  }
}

void Keyboard_Listener(ulong_t arg) {
  ulong_t * doIBuzz = (ulong_t*)arg;
  Keycode key_press;

  Print("Press F4 to turn on/off the speaker\n");

  while ((key_press = Wait_For_Key())) {    
    if (key_press == KEY_F4) {
      Print("\nToggling Speaker Port\n");
      SerialPrintLevel(100,"\nToggling Speaker Port\n");
      *doIBuzz = (*doIBuzz + 1) % 2;
    } else if (key_press == KEY_F5) {
      Print("\nMachine Restart\n");
      SerialPrintLevel(100,"\nMachine Restart\n");
      machine_real_restart();
    }
  }
  return;
}



extern char BSS_START, BSS_END;

extern char end;

/*
void VM_Thread(ulong_t arg) 
{
  int ret;
  struct VMDescriptor *vm = (struct VMDescriptor *) arg;

  SerialPrintLevel(100,"VM_Thread: Launching VM with (entry_ip=%x, exit_eip=%x, guest_esp=%x)\n",
	      vm->entry_ip, vm->exit_eip, vm->guest_esp);

  SerialPrintLevel(100,"VM_Thread: You should see nothing further from me\n");


  ret = VMLaunch(vm);


  SerialPrintLevel(100,"VM_Thread: uh oh...");

  switch (ret) { 
  case VMX_SUCCESS:
    SerialPrintLevel(100,"Normal VMExit Occurred\n");
    break;
  case VMX_FAIL_INVALID:
    SerialPrintLevel(100,"Possibile invalid VMCS (%.8x)\n", ret);
    break;
  case VMX_FAIL_VALID:
    SerialPrintLevel(100,"Valid VMCS, errorcode recorded in VMCS\n");
    break;
  case VMM_ERROR:
    SerialPrintLevel(100,"VMM Error\n");
    break;
  default:
    SerialPrintLevel(100,"VMLaunch returned unknown error (%.8x)\n", ret);
    break;
  }
  
  SerialPrintLevel(100,"VM_Thread: Spinning\n");
  while (1) {}
    
}
*/

int AllocateAndMapPagesForRange(uint_t start, uint_t length, pte_t template_pte)
{
  uint_t address;

  for (address=start;address<start+length;address+=PAGE_SIZE) { 
    void *page;
    pte_t pte = template_pte;
    
    page=Alloc_Page();
    KASSERT(page);
    
    pte.pageBaseAddr=PAGE_ALLIGNED_ADDR(page);

    KASSERT(MapPage((void*)address,&pte,1));
  }
  
  return 0;
}
    


/*
 * Kernel C code entry point.
 * Initializes kernel subsystems, mounts filesystems,
 * and spawns init process.
 */
void Main(struct Boot_Info* bootInfo)
{
  struct Kernel_Thread * key_thread;
  struct Kernel_Thread * spkr_thread;
  // struct Kernel_Thread * vm_thread;
  // struct VMDescriptor    vm;

  ulong_t doIBuzz = 0;

  Init_BSS();
  Init_Screen();


  InitSerial();
  Init_Mem(bootInfo);
  Init_CRC32();
  Init_TSS();
  Init_Interrupts();
  Init_Scheduler();
  Init_Traps();
  Init_Timer();
  Init_Keyboard();
  Init_VM(bootInfo);
  Init_Paging();

  //  Init_IDE();

  Print("Done; stalling\n");


  
#if 0
  SerialPrint("Dumping VM kernel Code (first 512 bytes @ 0x%x)\n",VM_KERNEL_START);
  SerialMemDump((unsigned char *)VM_KERNEL_START, 512);
  /*
    SerialPrint("Dumping kernel Code (first 512 bytes @ 0x%x)\n",KERNEL_START);
    SerialMemDump((unsigned char *)VM_KERNEL_START, 512);
  */
#endif

#if 1
  SerialPrint("Dumping GUEST KERNEL CODE (first 512*2 bytes @ 0x100000)\n");
  SerialMemDump((unsigned char *)0x100000, 512*2);
#endif




  SerialPrint("\n\nHello, Welcome to this horrid output-only serial interface\n");
  SerialPrint("Eventually, this will let us control the VMM\n\n");
 
  SerialPrint("\n\n===>");
  
  

  Init_VMM();

  
  SerialPrintLevel(1000,"Launching Noisemaker and keyboard listener threads\n");
  
  key_thread = Start_Kernel_Thread(Keyboard_Listener, (ulong_t)&doIBuzz, PRIORITY_NORMAL, false);
  spkr_thread = Start_Kernel_Thread(Buzzer, (ulong_t)&doIBuzz, PRIORITY_NORMAL, false);






  // Try to launch a real VM


  // We now map pages of physical memory into where we are going
  // to slap the vmxassist, bios, and vgabios code
  /*
  pte_t template_pte;

  template_pte.present=1;
  template_pte.flags=VM_WRITE|VM_READ|VM_USER|VM_EXEC;
  template_pte.accessed=0;
  template_pte.dirty=0;
  template_pte.pteAttribute=0;
  template_pte.globalPage=0;
  template_pte.kernelInfo=0;
  
  SerialPrintLevel(1000,"Allocating Pages for VM kernel\n");
  
#define SEGLEN (1024*64)

  AllocateAndMapPagesForRange(START_OF_VM+0x100000, VM_KERNEL_LENGTH / 512, template_pte);
*/
  // Now we should be copying into actual memory

  //SerialPrintLevel(1000,"Copying VM code from %x to %x (%d bytes)\n", VM_KERNEL_START, START_OF_VM+0x100000,VM_KERNEL_LENGTH);
  //memcpy((char*)(START_OF_VM+0x100000),(char*)VM_KERNEL_START,VM_KERNEL_LENGTH);

  //SerialPrintLevel(1000, "VM copied\n");

  /*
  // jump into vmxassist
  vm.entry_ip=(uint_t)0x00107fd0;
  vm.exit_eip=0;
  // Put the stack at 512K
  vm.guest_esp=(uint_t)4096 + 8192 - 4;
  *(unsigned int *)(vm.guest_esp) = 1024 * 1024;
  vm.guest_esp -= 4;
  *(unsigned int *)(vm.guest_esp) = 8;
  vm.guest_esp -= 4;
  *(unsigned int *)(vm.guest_esp) = vm.guest_esp + 4;;
  vm.guest_esp -= 4;
  *(unsigned int *)(vm.guest_esp) = vm.entry_ip;
  //  vm.guest_esp -= 4;

 
  SerialMemDump((unsigned char *)vm.entry_ip, 512);
  */
 
  // vm_thread = Start_Kernel_Thread(VM_Thread, (ulong_t)&vm,PRIORITY_NORMAL,false);

  
  SerialPrintLevel(1000,"Next: setup GDT\n");



  TODO("Write a Virtual Machine Monitor");
  
  
  /* Now this thread is done. */
  Exit(0);
}