|
- /***************************************************************************
- * Copyright (C) 2010 by Spencer Oliver *
- * spen@spen-soft.co.uk *
- * *
- * 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. *
- * *
- * This program is distributed in the hope that it will be useful, *
- * but WITHOUT ANY WARRANTY; without even the implied warranty of *
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
- * GNU General Public License for more details. *
- * *
- * You should have received a copy of the GNU General Public License *
- * along with this program; if not, write to the *
- * Free Software Foundation, Inc., *
- * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
- ***************************************************************************/
-
- .text
- .syntax unified
- .cpu cortex-m3
- .thumb
- .thumb_func
- .global write
-
- /*
- r0 - source address
- r1 - target address
- r2 - count (halfword-16bit)
- r3 - result
- r4 - temp
- */
-
- #define STM32_FLASH_CR_OFFSET 0x10 /* offset of CR register in FLASH struct */
- #define STM32_FLASH_SR_OFFSET 0x0c /* offset of CR register in FLASH struct */
-
- write:
- ldr r4, STM32_FLASH_BASE
- write_half_word:
- movs r3, #0x01
- str r3, [r4, #STM32_FLASH_CR_OFFSET] /* PG (bit0) == 1 => flash programming enabled */
- ldrh r3, [r0], #0x02 /* read one half-word from src, increment ptr */
- strh r3, [r1], #0x02 /* write one half-word from src, increment ptr */
- busy:
- ldr r3, [r4, #STM32_FLASH_SR_OFFSET]
- tst r3, #0x01 /* BSY (bit0) == 1 => operation in progress */
- beq busy /* wait more... */
- tst r3, #0x14 /* PGERR (bit2) == 1 or WRPRTERR (bit4) == 1 => error */
- bne exit /* fail... */
- subs r2, r2, #0x01 /* decrement counter */
- bne write_half_word /* write next half-word if anything left */
- exit:
- bkpt #0x00
-
- STM32_FLASH_BASE: .word 0x40022000 /* base address of FLASH struct */
|
