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/*
 * Copyright (C) Paul Mackerras 1997.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 * NOTE: this code runs in 32 bit mode and is packaged as ELF32.
 */

#include <asm/ppc_asm.tmpl>

        .text
        .globl  _start
_start:
        lis     r9,_start@h
        lis     r8,_etext@ha
        addi    r8,r8,_etext@l
1:      dcbf    r0,r9
        icbi    r0,r9
        addi    r9,r9,0x20
        cmplwi  0,r9,8
        blt     1b
        sync
        isync

        ## Clear out the BSS as per ANSI C requirements

        lis     r7,_end@ha
        addi    r7,r7,_end@l            # r7 = &_end 
        lis     r8,__bss_start@ha       # 
        addi    r8,r8,__bss_start@l     # r8 = &_bss_start

        ## Determine how large an area, in number of words, to clear

        subf    r7,r8,r7                # r7 = &_end - &_bss_start + 1 
        addi    r7,r7,3                 # r7 += 3 
        srwi.   r7,r7,2                 # r7 = size in words.
        beq     3f                      # If the size is zero, don't bother
        addi    r8,r8,-4                # r8 -= 4 
        mtctr   r7                      # SPRN_CTR = number of words to clear
        li      r0,0                    # r0 = 0
2:      stwu    r0,4(r8)                # Clear out a word
        bdnz    2b                      # Keep clearing until done
3:
        b       start