diff options
Diffstat (limited to 'arch/m68k/platform/68328/head-de2.S')
-rw-r--r-- | arch/m68k/platform/68328/head-de2.S | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/arch/m68k/platform/68328/head-de2.S b/arch/m68k/platform/68328/head-de2.S new file mode 100644 index 00000000000..f632fdcb93e --- /dev/null +++ b/arch/m68k/platform/68328/head-de2.S @@ -0,0 +1,128 @@ + +#define MEM_END 0x00800000 /* Memory size 8Mb */ + +#undef CRT_DEBUG + +.macro PUTC CHAR +#ifdef CRT_DEBUG + moveq #\CHAR, %d7 + jsr putc +#endif +.endm + + .global _start + .global _rambase + .global _ramvec + .global _ramstart + .global _ramend + + .data + +/* + * Set up the usable of RAM stuff + */ +_rambase: + .long 0 +_ramvec: + .long 0 +_ramstart: + .long 0 +_ramend: + .long 0 + + .text + +_start: + +/* + * Setup initial stack + */ + /* disable all interrupts */ + movew #0x2700, %sr + movel #-1, 0xfffff304 + movel #MEM_END-4, %sp + + PUTC '\r' + PUTC '\n' + PUTC 'A' + PUTC 'B' + +/* + * Determine end of RAM + */ + + movel #MEM_END, %a0 + movel %a0, _ramend + + PUTC 'C' + +/* + * Move ROM filesystem above bss :-) + */ + + moveal #_sbss, %a0 /* romfs at the start of bss */ + moveal #_ebss, %a1 /* Set up destination */ + movel %a0, %a2 /* Copy of bss start */ + + movel 8(%a0), %d1 /* Get size of ROMFS */ + addql #8, %d1 /* Allow for rounding */ + andl #0xfffffffc, %d1 /* Whole words */ + + addl %d1, %a0 /* Copy from end */ + addl %d1, %a1 /* Copy from end */ + movel %a1, _ramstart /* Set start of ram */ + +1: + movel -(%a0), %d0 /* Copy dword */ + movel %d0, -(%a1) + cmpl %a0, %a2 /* Check if at end */ + bne 1b + + PUTC 'D' + +/* + * Initialize BSS segment to 0 + */ + + lea _sbss, %a0 + lea _ebss, %a1 + + /* Copy 0 to %a0 until %a0 == %a1 */ +2: cmpal %a0, %a1 + beq 1f + clrl (%a0)+ + bra 2b +1: + + PUTC 'E' + +/* + * Load the current task pointer and stack + */ + + lea init_thread_union, %a0 + lea 0x2000(%a0), %sp + + PUTC 'F' + PUTC '\r' + PUTC '\n' + +/* + * Go + */ + + jmp start_kernel + +/* + * Local functions + */ + +#ifdef CRT_DEBUG +putc: + moveb %d7, 0xfffff907 +1: + movew 0xfffff906, %d7 + andw #0x2000, %d7 + beq 1b + rts +#endif |