xref: /openbmc/u-boot/include/reset.h (revision 00a457b2)
1 /*
2  * Copyright (c) 2015 Google, Inc
3  * Written by Simon Glass <sjg@chromium.org>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #ifndef __RESET_H
9 #define __RESET_H
10 
11 enum reset_t {
12 	RESET_WARM,	/* Reset CPU, keep GPIOs active */
13 	RESET_COLD,	/* Reset CPU and GPIOs */
14 	RESET_POWER,	/* Reset PMIC (remove and restore power) */
15 
16 	RESET_COUNT,
17 };
18 
19 struct reset_ops {
20 	/**
21 	 * request() - request a reset of the given type
22 	 *
23 	 * Note that this function may return before the reset takes effect.
24 	 *
25 	 * @type:	Reset type to request
26 	 * @return -EINPROGRESS if the reset has been started and
27 	 *		will complete soon, -EPROTONOSUPPORT if not supported
28 	 *		by this device, 0 if the reset has already happened
29 	 *		(in which case this method will not actually return)
30 	 */
31 	int (*request)(struct udevice *dev, enum reset_t type);
32 };
33 
34 #define reset_get_ops(dev)        ((struct reset_ops *)(dev)->driver->ops)
35 
36 /**
37  * reset_request() - request a reset
38  *
39  * @type:	Reset type to request
40  * @return 0 if OK, -EPROTONOSUPPORT if not supported by this device
41  */
42 int reset_request(struct udevice *dev, enum reset_t type);
43 
44 /**
45  * reset_walk() - cause a reset
46  *
47  * This works through the available reset devices until it finds one that can
48  * perform a reset. If the provided reset type is not available, the next one
49  * will be tried.
50  *
51  * If this function fails to reset, it will display a message and halt
52  *
53  * @type:	Reset type to request
54  * @return -EINPROGRESS if a reset is in progress, -ENOSYS if not available
55  */
56 int reset_walk(enum reset_t type);
57 
58 /**
59  * reset_walk_halt() - try to reset, otherwise halt
60  *
61  * This calls reset_walk(). If it returns, indicating that reset is not
62  * supported, it prints a message and halts.
63  */
64 void reset_walk_halt(enum reset_t type);
65 
66 /**
67  * reset_cpu() - calls reset_walk(RESET_WARM)
68  */
69 void reset_cpu(ulong addr);
70 
71 #endif
72