DRAM, Transition to C, Mainboard Fixup, Starting Kernel

• DRAM setup

  • non-portable, tricky, tough to figure out

• Transition to C

  • set up the stack and call a function to do the rest

• Mainboard fixup

  • turn on cacheing (MTRR) so that the kernel unzips in reasonable time
    • Otherwise it can take a minute or more
  • make all the FLASH available (rather than 64K or 128K)
    • requires some register manipulation, different for each chipset
  • minimal power management capabilities
  • do stuff Linux cannot (or will not) do:
    • turn clock interrupts on
    • a bit of PCI initialization ג€“ set Base Address Registers

• Inflate and run the kernel (snarfed from the kernel itself)

  • handle parameters, command line
  • make gunzip work in ROM environment (declare initialized arrays const)
  • jump to startup_32(), not to setup() as LILO does