xref: /arm-trusted-firmware/drivers/arm/sp805/sp805.c (revision 91f16700b400a8c0651d24a598fc48ee2997a0d7)
1*91f16700Schasinglulu /*
2*91f16700Schasinglulu  * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
3*91f16700Schasinglulu  *
4*91f16700Schasinglulu  * SPDX-License-Identifier: BSD-3-Clause
5*91f16700Schasinglulu  */
6*91f16700Schasinglulu 
7*91f16700Schasinglulu #include <stdint.h>
8*91f16700Schasinglulu 
9*91f16700Schasinglulu #include <drivers/arm/sp805.h>
10*91f16700Schasinglulu #include <lib/mmio.h>
11*91f16700Schasinglulu 
12*91f16700Schasinglulu /* Inline register access functions */
13*91f16700Schasinglulu 
14*91f16700Schasinglulu static inline void sp805_write_wdog_load(uintptr_t base, uint32_t value)
15*91f16700Schasinglulu {
16*91f16700Schasinglulu 	mmio_write_32(base + SP805_WDOG_LOAD_OFF, value);
17*91f16700Schasinglulu }
18*91f16700Schasinglulu 
19*91f16700Schasinglulu static inline void sp805_write_wdog_ctrl(uintptr_t base, uint32_t value)
20*91f16700Schasinglulu {
21*91f16700Schasinglulu 	mmio_write_32(base + SP805_WDOG_CTR_OFF, value);
22*91f16700Schasinglulu }
23*91f16700Schasinglulu 
24*91f16700Schasinglulu static inline void sp805_write_wdog_lock(uintptr_t base, uint32_t value)
25*91f16700Schasinglulu {
26*91f16700Schasinglulu 	mmio_write_32(base + SP805_WDOG_LOCK_OFF, value);
27*91f16700Schasinglulu }
28*91f16700Schasinglulu 
29*91f16700Schasinglulu 
30*91f16700Schasinglulu /* Public API implementation */
31*91f16700Schasinglulu 
32*91f16700Schasinglulu void sp805_start(uintptr_t base, unsigned int ticks)
33*91f16700Schasinglulu {
34*91f16700Schasinglulu 	sp805_write_wdog_load(base, ticks);
35*91f16700Schasinglulu 	sp805_write_wdog_ctrl(base, SP805_CTR_RESEN | SP805_CTR_INTEN);
36*91f16700Schasinglulu 	/* Lock registers access */
37*91f16700Schasinglulu 	sp805_write_wdog_lock(base, 0U);
38*91f16700Schasinglulu }
39*91f16700Schasinglulu 
40*91f16700Schasinglulu void sp805_stop(uintptr_t base)
41*91f16700Schasinglulu {
42*91f16700Schasinglulu 	sp805_write_wdog_lock(base, WDOG_UNLOCK_KEY);
43*91f16700Schasinglulu 	sp805_write_wdog_ctrl(base, 0U);
44*91f16700Schasinglulu }
45*91f16700Schasinglulu 
46*91f16700Schasinglulu void sp805_refresh(uintptr_t base, unsigned int ticks)
47*91f16700Schasinglulu {
48*91f16700Schasinglulu 	sp805_write_wdog_lock(base, WDOG_UNLOCK_KEY);
49*91f16700Schasinglulu 	sp805_write_wdog_load(base, ticks);
50*91f16700Schasinglulu 	sp805_write_wdog_lock(base, 0U);
51*91f16700Schasinglulu }
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