Init_machine the process that is called in kernel

Take tiny4412 as an example:

Arch/arm/mach-exynos/mach-tiny4412.c

" TINY4412 " )    /**/    . Boot_params    0x100,    . INIT_IRQ    = Exynos4_init_irq,    . map_io        = smdk4x12_map_io,    . init_machine     = smdk4x12_machine_init,    . Timer        = &Exynos4_timer,    .    Reserve = &exynos4_reserve,machine_end

which

#define Machine_start (_type,_name)            staticconststruct  machine_desc __mach_desc_# #_type     __used                             __attribute__ ((__section__ (". Arch.info.init")) = {        . nr        = mach_type_# #_type,            . Name        = _name,#define machine_end                \};

At startup:

Start_kernel-----INIT/MAIN.C

----> Setup_arch----arch/arm/kernel/setup.c

----> Mdesc = setup_machine_tags (Machine_arch_type); Here, the structure is found on the basis of Machine_arch_type.

----> Machine_desc = MDESC;

Paging_init, ---(mdesc) (ARCH/ARM/MM/MMU.C)

----> Devicemaps_init (MDESC)

----> Mdesc->map_io () called the function Smdk4x12_map_io

Init_machine the process that is called in kernel