diff options
Diffstat (limited to 'contrib')
| -rw-r--r-- | contrib/loaders/flash/mdr32fx.S | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/contrib/loaders/flash/mdr32fx.S b/contrib/loaders/flash/mdr32fx.S new file mode 100644 index 00000000..73f4b6fd --- /dev/null +++ b/contrib/loaders/flash/mdr32fx.S @@ -0,0 +1,125 @@ +/*************************************************************************** + * Copyright (C) 2011 by Andreas Fritiofson * + * andreas.fritiofson@gmail.com * + * * + * Copyright (C) 2013 by Paul Fertser * + * fercerpav@gmail.com * + * * + * 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., * + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * + ***************************************************************************/ + + .text + .syntax unified + .cpu cortex-m0 + .thumb + .thumb_func + .global write + + /* Params: + * r0 - flash base (in), status (out) + * r1 - count (32bit) + * r2 - workarea start + * r3 - workarea end + * r4 - target address + * Clobbered: + * r5 - rp + * r6 - wp, tmp + * r7 - current FLASH_CMD + */ + +#define FLASH_CMD 0x00 +#define FLASH_ADR 0x04 +#define FLASH_DI 0x08 + +#define FLASH_NVSTR (1 << 13) +#define FLASH_PROG (1 << 12) +#define FLASH_MAS1 (1 << 11) +#define FLASH_ERASE (1 << 10) +#define FLASH_SE (1 << 8) +#define FLASH_YE (1 << 7) +#define FLASH_XE (1 << 6) + + ldr r7, [r0, #FLASH_CMD] +wait_fifo: + ldr r6, [r2, #0] /* read wp */ + cmp r6, #0 /* abort if wp == 0 */ + beq exit + ldr r5, [r2, #4] /* read rp */ + cmp r5, r6 /* wait until rp != wp */ + beq wait_fifo + + ldr r6, [r5] /* "*target_address++ = *rp++" */ + str r4, [r0, #FLASH_ADR] + str r6, [r0, #FLASH_DI] + + ldr r6, =(FLASH_XE | FLASH_PROG) + orrs r7, r7, r6 + str r7, [r0, #FLASH_CMD] + # wait 5us + movs r6, #5 + bl delay + ldr r6, =#FLASH_NVSTR + orrs r7, r7, r6 + str r7, [r0, #FLASH_CMD] + # wait 10us + movs r6, #13 + bl delay + movs r6, #FLASH_YE + orrs r7, r7, r6 + str r7, [r0, #FLASH_CMD] + # wait 40us + movs r6, #61 + bl delay + movs r6, #FLASH_YE + bics r7, r7, r6 + str r7, [r0, #FLASH_CMD] + ldr r6, =#FLASH_PROG + bics r7, r7, r6 + str r7, [r0, #FLASH_CMD] + # wait 5us + movs r6, #5 + bl delay + ldr r6, =#(FLASH_XE | FLASH_NVSTR) + bics r7, r7, r6 + str r7, [r0, #FLASH_CMD] + + adds r5, #4 + adds r4, #4 + + cmp r5, r3 /* wrap rp at end of buffer */ + bcc no_wrap + mov r5, r2 + adds r5, #8 +no_wrap: + str r5, [r2, #4] /* store rp */ + subs r1, r1, #1 /* decrement word count */ + cmp r1, #0 + beq exit /* loop if not done */ + b wait_fifo +exit: + mov r0, r6 /* return status in r0 */ + bkpt #0 + + /* r6 - in + * for r6 == 1 it'll take: + * 1 (prepare operand) + 4 (bl) + 2 (subs+cmp) + 1 (bne) + 3 (b) -> + * 11 tacts == 1.4us with 8MHz + * every extra iteration will take 5 tacts == 0.6us */ +delay: + subs r6, r6, #1 + cmp r6, #0 + bne delay + bx lr |