/* $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 .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