src/kern/priv.c


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#include "kern/priv.h"

void set_control_register(uint32_t reg)
{
  asm volatile("msr control, %0" : "=r"(reg) :);
}

uint32_t get_control_register()
{
  uint32_t control;
  asm volatile("mrs %0, control" : "=r"(control) :);
  return control;
}

void enter_user_mode()
{
  asm volatile (
      "mov r0, #1\n\t"
      "msr control, r0\n\t"
    );

  // uint32_t creg = get_control_register();
  // set_control_register(creg | 1);
}