| /* $Id: head.S,v 1.7 2003/09/01 17:58:19 lethal Exp $ |
| * |
| * arch/sh/kernel/head.S |
| * |
| * Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| * |
| * Head.S contains the SH exception handlers and startup code. |
| */ |
| #include <linux/linkage.h> |
| |
| .section .empty_zero_page, "aw" |
| ENTRY(empty_zero_page) |
| .long 1 /* MOUNT_ROOT_RDONLY */ |
| .long 0 /* RAMDISK_FLAGS */ |
| .long 0x0200 /* ORIG_ROOT_DEV */ |
| .long 1 /* LOADER_TYPE */ |
| .long 0x00360000 /* INITRD_START */ |
| .long 0x000a0000 /* INITRD_SIZE */ |
| .long 0 |
| .balign 4096,0,4096 |
| |
| .text |
| /* |
| * Condition at the entry of _stext: |
| * |
| * BSC has already been initialized. |
| * INTC may or may not be initialized. |
| * VBR may or may not be initialized. |
| * MMU may or may not be initialized. |
| * Cache may or may not be initialized. |
| * Hardware (including on-chip modules) may or may not be initialized. |
| * |
| */ |
| ENTRY(_stext) |
| ! Initialize Status Register |
| mov.l 1f, r0 ! MD=1, RB=0, BL=0, IMASK=0xF |
| ldc r0, sr |
| ! Initialize global interrupt mask |
| mov #0, r0 |
| ldc r0, r6_bank |
| ! |
| mov.l 2f, r0 |
| mov r0, r15 ! Set initial r15 (stack pointer) |
| mov #0x20, r1 ! |
| shll8 r1 ! r1 = 8192 |
| sub r1, r0 ! |
| ldc r0, r7_bank ! ... and initial thread_info |
| ! |
| ! Additional CPU initialization |
| mov.l 6f, r0 |
| jsr @r0 |
| nop |
| ! Clear BSS area |
| mov.l 3f, r1 |
| add #4, r1 |
| mov.l 4f, r2 |
| mov #0, r0 |
| 9: cmp/hs r2, r1 |
| bf/s 9b ! while (r1 < r2) |
| mov.l r0,@-r2 |
| ! Start kernel |
| mov.l 5f, r0 |
| jmp @r0 |
| nop |
| |
| .balign 4 |
| 1: .long 0x400080F0 ! MD=1, RB=0, BL=0, FD=1, IMASK=0xF |
| 2: .long stack |
| 3: .long __bss_start |
| 4: .long _end |
| 5: .long start_kernel |
| 6: .long sh_cpu_init |