1. * 1. Set up initial environment for calling board_init_f().
   
2. *    This environment only provides a stack and a place to store
   
3. *    the GD ('global data') structure, both located in some readily
   
4. *    available RAM (SRAM, locked cache...). In this context, VARIABLE
   
5. *    global data, initialized or not (BSS), are UNAVAILABLE; only
   
6. *    CONSTANT initialized data are available.
   
7. *
   
8. * 2. Call board_init_f(). This function prepares the hardware for
   
9. *    execution from system RAM (DRAM, DDR...) As system RAM may not
   
10. *    be available yet, , board_init_f() must use the current GD to
    
11. *    store any data which must be passed on to later stages. These
    
12. *    data include the relocation destination, the future stack, and
    
13. *    the future GD location.
    
14. *
    
15. * (the following applies only to non-SPL builds)
    
16. *
    
17. * 3. Set up intermediate environment where the stack and GD are the
    
18. *    ones allocated by board_init_f() in system RAM, but BSS and
    
19. *    initialized non-const data are still not available.
    
20. *
    
21. * 4. Call relocate_code(). This function relocates U-Boot from its
    
22. *    current location into the relocation destination computed by
    
23. *    board_init_f().
    
24. *
    
25. * 5. Set up final environment for calling board_init_r(). This
    
26. *    environment has BSS (initialized to 0), initialized non-const
    
27. *    data (initialized to their intended value), and stack in system
    
28. *    RAM. GD has retained values set by board_init_f(). Some CPUs
    
29. *    have some work left to do at this point regarding memory, so
    
30. *    call c_runtime_cpu_setup.
    
31. *
    
32. * 6. Branch to board_init_r().

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