/**************************************************************************************
 Copyright (c) 2002 The UbixOS Project
 All rights reserved.

 Redistribution and use in source and binary forms, with or without modification,
 are prohibited.

 $Id$

**************************************************************************************/

#include <vmm/memory.h>
#include <vmm/paging.h>
#include <ubixos/io.h>

mMap *memoryMap = (mMap *) 0x100000;
int numPages;

int countMemory() {
  register unsigned long *mem;
  unsigned long memCount=-1, tempMemory;
  unsigned short  memKb=0;
  unsigned char   irq1State, irq2State;
  unsigned long cr0;

  /* Save States Of IRQ 1 & 2 */
  irq1State=inportByte(0x21);
  irq2State=inportByte(0xA1);

  /* Shut Off Both IRQS */
  outportByte(0x21, 0xFF);
  outportByte(0xA1, 0xFF);

  /* Save CR0 */
  asm(
    "movl %%cr0, %%ebx\n"
    : "=a"(cr0)
    :
    : "ebx"
    );

  asm("wbinvd");
  asm(
    "movl %%ebx, %%cr0\n"
    :
    : "a" (cr0 | 0x00000001 | 0x40000000 | 0x20000000)
    : "ebx"
    );

  while(memKb<4096 && memCount!=0) {
    memKb++;
    if (memCount == -1) memCount = 0;
    memCount+=1024*1024;
    mem=(unsigned long *)memCount;
    tempMemory=*mem;
    *mem=0x55AA55AA;
    asm("":::"memory");
    if (*mem!=0x55AA55AA) {
      memCount=0;
      }
    else {
      *mem=0xAA55AA55;
      asm("":::"memory");
      if (*mem!=0xAA55AA55) {
        memCount=0;
        }
      }
    asm("":::"memory");
    *mem=tempMemory;
    }
  asm(
    "movl %%ebx, %%cr0\n"
    :
    : "a" (cr0)
    : "ebx"
    );

  /* Return IRQ 1 & 2's States */
  outportByte(0x21, irq1State);
  outportByte(0xA1, irq2State);
  numPages = (memKb*1024*1024)/4096;
  return(memKb<<20);
  }

void initMmap() {
  int i=0;
  memoryMap = (mMap *) 0x100000;
  for (i=0;i<numPages;i++) {
    memoryMap[i].status = memNotavail;
    memoryMap[i].pid = -1;
    memoryMap[i].pageAddr = i*4096;
    }
  for (i=(memoryStart/4096);i<numPages;i++) {
    memoryMap[i].status = memAvail;
    }
  }

unsigned long findFreepage(int pid) {
  int i=0;
  for (i=0;i<=numPages;i++) {
    if (memoryMap[i].status == memAvail) {
      memoryMap[i].status = memNotavail;
      memoryMap[i].pid = pid;
      return(memoryMap[i].pageAddr);
      }
    }
  return(-1);
  }

void freePage(unsigned long pageAddr) {
  int i=0;
  i = (pageAddr/4096);
  memoryMap[i].status = memAvail;
  }

void freeProcesspages(int pid) {
  int i=0;
  for (i=0;i<numPages;i++) {
    if (memoryMap[i].pid == pid) {
      memoryMap[i].status = memAvail;
      }
    }
  }