1, define the virtual address, a physical address (28)
2, set the SVC mode, test hardware CPU ID number , machine code is legitimate, check uboot pass parameters to the kernel ATAGS the correct format, build page tables. (80-90)
3, copy the data section, clear the bss segment , saved cpu id number, machine code, Tag parameter passing the first address , jump to C language runtime phase (99) __switch_data ------> __mmap_switched