Clean up and comments.

This commit is contained in:
Vincent Rivière
2012-11-12 15:41:09 +00:00
parent 0404bf0721
commit 75a92fa9e0

View File

@@ -1,19 +1,33 @@
/* This object file must be the first to be linked,
* so it will be placed at the very beginning of the ROM.
*/
.equ MCF_MMU_MMUCR, __MMUBAR + 0
.global _startup
.global _rom_header
.global _rom_entry
.extern _initialize_hardware
.extern _rt_mbar
_startup:
bra.s warmstart
jmp ___BOOT_FLASH + 8 /* that's also our reset vector */
/* ROM header */
_rom_header:
/* The first long is supposed to be the initial SP.
* We replace it by bra.s to allow running the ROM from the first byte.
* Then we add a fake jmp instruction for pretty disassembly.
*/
bra.s _rom_entry // Short jump to the real entry point
.short 0x4ef9 // Fake jmp instruction
/* The second long is the initial PC */
.long _rom_entry // Real entry point
/* ROM entry point */
_rom_entry:
/* disable interrupts */
warmstart:
move.w #0x2700,SR
/* Initialize MBAR */
move.l #__MBAR,d0
movec d0,MBAR
move.l d0,_rt_mbar