#define PMC_SCRATCH0 0x7000e450
#define PMC_CNTRL 0x7000e400
#define EMMC_BASE 0x70000000 // Just a test address for mapping

void _start() {
  unsigned int val = *(volatile unsigned int *)0x40000000;

  *(volatile unsigned int *)(PMC_SCRATCH0) = val;
  *(volatile unsigned int *)(PMC_CNTRL) |= (1 << 4);
  while (1)
    ;
}