Add the contrib file for the armv7m arch

Signed-off-by: Jonathan Dumaresq <jdumaresq@cimeq.qc.ca>

contrib/loaders/flash/armv7m_cfi_span_16.s

+/***************************************************************************
+ *   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
+	.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, 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