contrib/loaders/flash/stm32lx.S

   1 /***************************************************************************
   2  *   Copyright (C) 2010 by Spencer Oliver                                  *
   3  *   spen@spen-soft.co.uk                                                  *
   4  *                                                                         *
   5  *   Copyright (C) 2011 Øyvind Harboe                                      *
   6  *   oyvind.harboe@zylin.com                                               *
   7  *                                                                         *
   8  *   Copyright (C) 2011 Clement Burin des Roziers                          *
   9  *   clement.burin-des-roziers@hikob.com                                   *
  10  *                                                                         *
  11  *   Copyright (C) 2017 Armin van der Togt                                 *
  12  *   armin@otheruse.nl                                                     *
  13  *                                                                         *
  14  *   This program is free software; you can redistribute it and/or modify  *
  15  *   it under the terms of the GNU General Public License as published by  *
  16  *   the Free Software Foundation; either version 2 of the License, or     *
  17  *   (at your option) any later version.                                   *
  18  *                                                                         *
  19  *   This program is distributed in the hope that it will be useful,       *
  20  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  21  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  22  *   GNU General Public License for more details.                          *
  23  *                                                                         *
  24  *   You should have received a copy of the GNU General Public License     *
  25  *   along with this program; if not, write to the                         *
  26  *   Free Software Foundation, Inc.,                                       *
  27  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
  28  ***************************************************************************/
  29
  30
  31 // Build : arm-eabi-gcc -c stm32lx.S
  32         .text
  33         .syntax unified
  34         .cpu cortex-m0
  35         .thumb
  36         .thumb_func
  37         .global write
  38
  39 /*
  40         r0 - destination address
  41         r1 - source address
  42         r2 - count
  43 */
  44
  45         // r2 = source + count * 4
  46         lsls    r2, r2, #2
  47         adds    r2, r1, r2
  48         // Go to compare
  49         b       test_done
  50 write_word:
  51         // load word from address in r1 and increase r1 by 4
  52         ldmia r1!, {r3}
  53         // store word to address in r0 and increase r0 by 4
  54         stmia r0!, {r3}
  55 test_done:
  56         // compare r1 and r2
  57         cmp     r1, r2
  58         // loop if not equal
  59         bne     write_word
  60
  61         // Set breakpoint to exit
  62         bkpt    #0x00
  63