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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