This chapter describes the linux kernel boot process. You will see here a couple of posts which describe the full cycle of the kernel loading process:

From the bootloader to kernel - describes all stages from turning on the computer to before the first instruction of the kernel;
First steps in the kernel setup code - describes first steps in the kernel setup code. You will see heap initialization, querying of different parameters like EDD, IST and etc...
Video mode initialization and transition to protected mode - describes video mode initialization in the kernel setup code and transition to protected mode.
Transition to 64-bit mode - describes preparation for transition into 64-bit mode and transition into it.
Kernel Decompression - describes preparation before kernel decompression and directly decompression.