tinyriscv-openocd/contrib/loaders/flash/armv7m_cfi_span_16.s

82 lines
2.7 KiB
ArmAsm

/***************************************************************************
* Copyright (C) 2005, 2007 by Dominic Rath *
* Dominic.Rath@gmx.de *
* Copyright (C) 2010 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
.arch armv7-m
.thumb
.thumb_func
.align 2
/* input parameters - */
/* R0 = source address */
/* R1 = destination address */
/* R2 = number of writes */
/* R3 = flash write command */
/* R4 = constant to mask DQ7 bits (also used for Dq5 with shift) */
/* output parameters - */
/* R5 = 0x80 ok 0x00 bad */
/* temp registers - */
/* R6 = value read from flash to test status */
/* R7 = holding register */
/* unlock registers - */
/* R8 = unlock1_addr */
/* R9 = unlock1_cmd */
/* R10 = unlock2_addr */
/* R11 = unlock2_cmd */
code:
ldrh r5, [r0], #2
strh r9, [r8]
strh r11, [r10]
strh r3, [r8]
strh r5, [r1]
nop
busy:
ldrh r6, [r1]
eor r7, r5, r6
ands r7, r4, r7
beq cont /* b if DQ7 == Data7 */
ands r6, r6, r4, lsr #2
beq busy /* b if DQ5 low */
ldrh r6, [r1]
eor r7, r5, r6
ands r7, r4, r7
beq cont /* b if DQ7 == Data7 */
mov r5, #0 /* 0x0 - return 0x00, error */
bne done
cont:
subs r2, r2, #1 /* 0x1 */
beq success
add r1, r1, #2 /* 0x2 */
b code
success:
mov r5, #128 /* 0x80 */
b done
done:
bkpt #0
.end