tinyriscv-openocd/contrib/loaders/flash/armv4_5_cfi_span_16_dq7.s

67 lines
2.4 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., *
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *
***************************************************************************/
.text
.arm
.arch armv4
.section .init
/* 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, #0x80
bne busy
subs r2, r2, #1 /* 0x1 */
moveq r5, #128 /* 0x80 */
beq done
add r1, r1, #2 /* 0x2 */
b code
done:
b done
.end