smokers_memtest

//this is placed at the end of board.c (as there's no way that I know of to cancel #pragma GCC optimize after it's applied)

#define ONEMEG ((1<<20)/sizeof(u32))
#define MAXERRORS 50

#ifdef SMOKEMEM
//HERE BE DRAGONS. No compiler optimization beyond this point!
#pragma GCC optimize "O0"

//this memtest writes a fixed value to memory and reads it back in 1M blocks.
static void smokers_memtest(u32 pattern)
{
  printf("smokers_memtest started, pattern %08x\n", pattern);
  const u8* init_addr = (u8*) 0x40000000;
  u32 errorcount=0;
  u32* addr;
  for(uint megs = 0; megs < 1024; megs++)
  {
    u32* baseaddr = (u32*)init_addr+ONEMEG*megs;
    if(!(megs % 128)) {
      printf("\n%d M || 0x%x\n", megs, baseaddr);
    }
    printf("."); //writing block
    for(u32 offset = 0; offset < ONEMEG; ++offset)
    {
      *((volatile uint32_t *)baseaddr + offset) = pattern;
    }
    printf("'"); //reading block
    for(u32 offset = 0; offset < ONEMEG; ++offset)
    {
      if (readl((u32*)baseaddr + offset) != pattern) {
        if(++errorcount < MAXERRORS)
          printf("\nerror @ %x: %x\n", (u32)addr, readl(addr));
        //break;
      }
    }
  }
  printf("\n%d errors in pattern %08x\n",errorcount, pattern);
  errorcount=0;
  printf("smokers_memtest finished\n");
};

//this memtest overwrites the whole DRAM with values of magic^addr, and then reads the whole DRAM back.
static void magic_memtest(u32 magicval){
  printf("\n magic_memtest started, magic value: %08x\n", magicval);
  const u8* init_addr = (u8*) 0x40000000;
  const unsigned meg_shift = 3; //8M steps
  u32 errorcount=0;
  u32* addr;
  printf("writing...");
  for(uint megs = 0; megs < 1024; megs+=1<<meg_shift)
  {
    u32* baseaddr = (u32*)init_addr+ONEMEG*megs;
    if(!(megs % 128)) printf("\n%d M || 0x%x\n", megs, baseaddr);

    for(u32 offset = 0; offset < ONEMEG<<meg_shift; ++offset)
    {
      addr = (u32*)baseaddr+offset;
      *((volatile uint32_t *)baseaddr + offset) = magicval^(u32)addr;
    }
    printf(".");
  }
  printf("\nreading...");
  for(uint megs = 0; megs < 1024; megs+=1<<meg_shift)
  {
    u32* baseaddr = (u32*)init_addr+ONEMEG*megs;
    if(!(megs % 128)) printf("\n%d M || 0x%x\n", megs, baseaddr);

    for(u32 offset = 0; offset < ONEMEG<<meg_shift; ++offset)
    {
      addr = (u32*)baseaddr+offset;
      if ((u32)readl(addr) != (magicval^((u32)addr))) {
        if(++errorcount < MAXERRORS)
          printf("\nerror @ %08x: expected %08x, got %08x\n", (u32)addr, magicval^((u32)addr), (u32)readl(addr));
        //break;
      }
    }
    printf("'");
  }

  printf("\n\n%d errors for magic %08x\n",errorcount, magicval);
  printf("magic_memtest finished\n");
}
#endif //SMOKEMEM