xref: /rk3399_ARM-atf/drivers/arm/sp805/sp805.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 <mmio.h>
32 #include <sp805.h>
33 #include <stdint.h>
34 
35 /* Inline register access functions */
36 
37 static inline void sp805_write_wdog_load(uintptr_t base, unsigned long value)
38 {
39 	mmio_write_32(base + SP805_WDOG_LOAD_OFF, value);
40 }
41 
42 static inline void sp805_write_wdog_ctrl(uintptr_t base, unsigned long value)
43 {
44 	mmio_write_32(base + SP805_WDOG_CTR_OFF, value);
45 }
46 
47 static inline void sp805_write_wdog_lock(uintptr_t base, unsigned long value)
48 {
49 	mmio_write_32(base + SP805_WDOG_LOCK_OFF, value);
50 }
51 
52 
53 /* Public API implementation */
54 
55 void sp805_start(uintptr_t base, unsigned long ticks)
56 {
57 	sp805_write_wdog_load(base, ticks);
58 	sp805_write_wdog_ctrl(base, SP805_CTR_RESEN | SP805_CTR_INTEN);
59 	/* Lock registers access */
60 	sp805_write_wdog_lock(base, 0);
61 }
62 
63 void sp805_stop(uintptr_t base)
64 {
65 	sp805_write_wdog_lock(base, WDOG_UNLOCK_KEY);
66 	sp805_write_wdog_ctrl(base, 0);
67 }
68 
69 void sp805_refresh(uintptr_t base, unsigned long ticks)
70 {
71 	sp805_write_wdog_lock(base, WDOG_UNLOCK_KEY);
72 	sp805_write_wdog_load(base, ticks);
73 	sp805_write_wdog_lock(base, 0);
74 }
75