/*
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * Copyright (c) 2014, Normmatt
 *
 * Alternatively, the contents of this file may be used under the terms
 * of the GNU General Public License Version 2, as described below:
 *
 * This file is free software: you may copy, redistribute 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 file 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, see http://www.gnu.org/licenses/.
 */

.arm
.global ioDelay
.type   ioDelay STT_FUNC

@ioDelay ( u32 us )
ioDelay:
	ldr r1, =0x18000000  @ VRAM
1:
	@ Loop doing uncached reads from VRAM to make loop timing more reliable
	ldr r2, [r1]
	subs r0, #1
	bgt 1b
	bx lr