xref: /rk3399_ARM-atf/plat/nvidia/tegra/common/tegra_delay_timer.c (revision 51faada71a219a8b94cd8d8e423f0f22e9da4d8f)
1 /*
2  * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  * Redistributions of source code must retain the above copyright notice, this
8  * list of conditions and the following disclaimer.
9  *
10  * Redistributions in binary form must reproduce the above copyright notice,
11  * this list of conditions and the following disclaimer in the documentation
12  * and/or other materials provided with the distribution.
13  *
14  * Neither the name of ARM nor the names of its contributors may be used
15  * to endorse or promote products derived from this software without specific
16  * prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <delay_timer.h>
32 #include <mmio.h>
33 #include <tegra_def.h>
34 
35 static uint32_t tegra_timerus_get_value(void)
36 {
37 	return mmio_read_32(TEGRA_TMRUS_BASE);
38 }
39 
40 static const timer_ops_t tegra_timer_ops = {
41 	.get_timer_value	= tegra_timerus_get_value,
42 	.clk_mult		= 1,
43 	.clk_div		= 1,
44 };
45 
46 /*
47  * Initialise the on-chip free rolling us counter as the delay
48  * timer.
49  */
50 void tegra_delay_timer_init(void)
51 {
52 	timer_init(&tegra_timer_ops);
53 }
54