#include <stdio.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <linux/types.h>
#include <linux/agpgart.h>
#include <asm/mtrr.h>
#include <errno.h>

unsigned char *gart;
int gartfd;
int mtrr;

int usec( void ) {
  struct timeval tv;
  struct timezone tz;
  
  gettimeofday( &tv, &tz );
  return (tv.tv_sec & 2047) * 1000000 + tv.tv_usec;
}

int MemoryBenchmark( void *buffer, int dwords ) {
  int             i;
  int             start, end;
  int             mb;
  int             *base;
  
  base = (int *)buffer;
  start = usec();
  for ( i = 0 ; i < dwords ; i += 8 ) {
    base[i] =
      base[i+1] =
      base[i+2] =
      base[i+3] =
      base[i+4] =
      base[i+5] =
      base[i+6] =
      base[i+7] = 0x15151515;         /* dmapad nops */
  }
  end = usec();
  mb = ( (float)dwords / 0x40000 ) * 1000000 / (end - start);
  printf("MemoryBenchmark: %i mb/s\n", mb );
  return mb;
}

int insert_gart(int page, int size)
{
   agp_allocate entry;
   agp_bind bind;
   
   entry.type = 0;
   entry.pg_count = size;
#ifdef DEBUG
   printf("Using AGPIOC_ALLOCATE\n");
#endif
   if(ioctl(gartfd, AGPIOC_ALLOCATE, &entry) != 0)
    {
      perror("ioctl(AGPIOC_ALLOCATE)");
      exit(1);
    }
   
   bind.key = entry.key;
   bind.pg_start = page;
#ifdef DEBUG
   printf("Using AGPIOC_BIND\n");
#endif
   if(ioctl(gartfd, AGPIOC_BIND, &bind))
     {
	perror("ioctl(AGPIOC_BIND)");
	exit(1);
     }
   
   printf("entry.key : %i\n", entry.key);
   
   return(entry.key);
}

int unbind_gart(int key)
{
   agp_unbind unbind;
   
   unbind.key = key;
#ifdef DEBUG
   printf("Using AGPIOC_UNBIND\n");
#endif
   if(ioctl(gartfd, AGPIOC_UNBIND, &unbind) != 0)
     {
	perror("ioctl(AGPIOC_UNBIND)");
	exit(1);
     }
   
   return(0);
}

int bind_gart(int key, int page)
{
   agp_bind bind;
   
   bind.key = key;
   bind.pg_start = page;
#ifdef DEBUG
   printf("Using AGPIOC_BIND\n");
#endif
   if(ioctl(gartfd, AGPIOC_BIND, &bind) != 0)
     {
	perror("ioctl(AGPIOC_BIND)");
	exit(1);
     }
   
   return(0);
}

int remove_gart(int key)
{
#ifdef DEBUG
   printf("Using AGPIOC_DEALLOCATE\n");
#endif
  if(ioctl(gartfd, AGPIOC_DEALLOCATE, key) != 0)
    {
      perror("ioctl(GARTIOCREMOVE)");
      exit(1);
    }
   
   return(0);
}

void openmtrr(void) 
{
   if ((mtrr = open("/proc/mtrr", O_WRONLY, 0)) == -1) 
     {
	if (errno == ENOENT) {
	   perror("/proc/mtrr not found: MTRR not enabled\n");
	}  else {
	   perror("Error opening /proc/mtrr:");
	   perror("MTRR not enabled\n");
	   exit(1);
	}
	return;
     }
}

int CoverRangeWithMTRR( int base, int range, int type )
{
   int          count;   
      
   /* set it if we aren't just checking the number */
   if ( type != -1 ) {
      struct mtrr_sentry sentry;
      
      sentry.base = base;
      sentry.size = range;
      sentry.type = type;
      
      if ( ioctl(mtrr, MTRRIOC_ADD_ENTRY, &sentry) == -1 ) {
	 perror("mtrr");
	 exit(1);
      }
   }
   
}

int init_agp(void)
{
   agp_info info;
   agp_setup setup;

#ifdef DEBUG
   printf("Using AGPIOC_ACQUIRE\n");
#endif
   if(ioctl(gartfd, AGPIOC_ACQUIRE) != 0)
     {
	perror("ioctl(AGPIOC_ACQUIRE)");
	exit(1);
     }
#ifdef DEBUG
   printf("Using AGPIOC_INFO\n");
#endif
   if(ioctl(gartfd, AGPIOC_INFO, &info) != 0)
     {
	perror("ioctl(AGPIOC_INFO)");
	exit(1);
     }
   
   printf("version: %i.%i\n", info.version.major, info.version.minor);
   printf("bridge id: 0x%lx\n", info.bridge_id);
   printf("agp_mode: 0x%lx\n", info.agp_mode);
   printf("aper_base: 0x%lx\n", info.aper_base);
   printf("aper_size: %i\n", info.aper_size);
   printf("pg_total: %i\n", info.pg_total);
   printf("pg_system: %i\n", info.pg_system);
   printf("pg_used: %i\n", info.pg_used);

   openmtrr();
   if (mtrr != -1) { 
     CoverRangeWithMTRR(info.aper_base, info.aper_size * 0x100000, 
       MTRR_TYPE_WRCOMB);
   }

   gart = mmap(NULL, info.aper_size * 0x100000, PROT_READ | PROT_WRITE, MAP_SHARED, gartfd, 0);

   if(gart == (unsigned char *) 0xffffffff)
     {
	perror("mmap");
	close(gartfd);
	exit(1);
     }	
   
   setup.agp_mode = info.agp_mode;
#ifdef DEBUG
   printf("Using AGPIOC_SETUP\n");
#endif
   if(ioctl(gartfd, AGPIOC_SETUP, &setup) != 0)
     {
	perror("ioctl(AGPIOC_SETUP)");
	exit(1);
     }
   
   return(0);
}

int xchangeDummy;

void FlushWriteCombining( void ) {
	__asm__ volatile( " push %%eax ; xchg %%eax, %0 ; pop %%eax" : : "m" (xchangeDummy));
	__asm__ volatile( " push %%eax ; push %%ebx ; push %%ecx ; push %%edx ; movl $0,%%eax ; cpuid ; pop %%edx ; pop %%ecx ; pop %%ebx ; pop %%eax" : /* no outputs */ :  /* no inputs */ );
}

void BenchMark()
{
  int i, worked = 1;

  i = MemoryBenchmark(gart, (1024 * 1024 * 4) / 4) +
    MemoryBenchmark(gart, (1024 * 1024 * 4) / 4) +
    MemoryBenchmark(gart, (1024 * 1024 * 4) / 4);
  
  printf("Average speed: %i mb/s\n", i /3);
  
  printf("Testing data integrity (1st pass): ");
  fflush(stdout);
   
  FlushWriteCombining();
  
  for (i=0; i < 8 * 0x100000; i++)
    {
      gart[i] = i % 256;
    }
   
  FlushWriteCombining();
   
  
  for (i=0; i < 8 * 0x100000; i++)
    {
       if(!(gart[i] == i % 256))
	 {
#ifdef DEBUG
	    printf("failed on %i, gart[i] = %i\n", i, gart[i]);
#endif
	    worked = 0;
	 }
    }
  
  if (!worked)
    printf("failed on first pass!\n");
  else
    printf("passed on first pass.\n");
   
   unbind_gart(0);
   unbind_gart(1);
   bind_gart(0, 0);
   bind_gart(1, 1024);

   worked = 1;
   printf("Testing data integrity (2nd pass): ");
   fflush(stdout);
   
   for (i=0; i < 8 * 0x100000; i++)
    {
       if(!(gart[i] == i % 256))
	 {
#ifdef DEBUG
	    printf("failed on %i, gart[i] = %i\n", i, gart[i]);
#endif
	    worked = 0;
	 }
    }

   if (!worked)
    printf("failed on second pass!\n");
  else
    printf("passed on second pass.\n");
}

int main()
{
   int i;
   int key;
   int key2;
   agp_info info;
  
   gartfd = open("/dev/agpgart", O_RDWR);
   if (gartfd == -1)
     {	
	perror("open");
	exit(1);
     }
   
   init_agp();
   
   key = insert_gart(0, 1024);
   key2 = insert_gart(1024, 1024);
   
#ifdef DEBUG
   printf("Using AGPIOC_INFO\n");
   if(ioctl(gartfd, AGPIOC_INFO, &info) != 0)
     {
	perror("ioctl(AGPIOC_INFO)");
	exit(1);
     }
   
   printf("version: %i.%i\n", info.version.major, info.version.minor);
   printf("bridge id: 0x%lx\n", info.bridge_id);
   printf("agp_mode: 0x%lx\n", info.agp_mode);
   printf("aper_base: 0x%lx\n", info.aper_base);
   printf("aper_size: %i\n", info.aper_size);
   printf("pg_total: %i\n", info.pg_total);
   printf("pg_system: %i\n", info.pg_system);
   printf("pg_used: %i\n", info.pg_used);
#endif
   
   printf("Allocated 8 megs of GART memory\n");
   
   BenchMark();
   
   remove_gart(key);
   remove_gart(key2);

#ifdef DEBUG   
   printf("Using AGPIOC_RELEASE\n");
#endif
   if(ioctl(gartfd, AGPIOC_RELEASE) != 0)
     {
	perror("ioctl(AGPIOC_RELEASE)");
	exit(1);
     }
   
   close(gartfd);
}