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DEFINITIONS

1. boot_entry

   1 /*-
   2  * Copyright (c) 2008, Kohsuke Ohtani
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the author nor the names of any co-contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  30 /*
  31  * head.S - generic header code for ARM platforms.
  32  */
  34 #include <conf/config.h>
  35 #include <machine/memory.h>
  36 #include <machine/syspage.h>
  38 #define ENTRY(x) .global x; .align; x##:
  40         .section ".text","ax"
  41         .code 32
  42 /*
  43  * Loader entry point
  44  */
ENTRY(boot_entry)
  46         b       start_vector
  48         .align
  49         .code 32
  50 stack_end:      .word   (BOOTSTKTOP - KERNBASE)
  52 start_vector:
  53         mov     r0, #0xd3               /* Enter SVC mode, Disable IRQ,FIQ */
  54         msr     cpsr_c, r0
  55         ldr     sp, stack_end
  57         adr     r0, thumb_mode + 1
  58         bx      r0
  59         .code 16
  60 thumb_mode:
  62         ldr     r0, =main
  63         bx      r0                      /* Change to ARM mode */
  65         .section .tail,"ax"
  66 dummy:
  67         .byte   0xff
  69 .end