1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2018 Theobroma Systems Design und Consulting GmbH
4  */
5 
6 #include <common.h>
7 #include <dm.h>
8 #include <errno.h>
9 #include <bootcount.h>
10 
11 int dm_bootcount_get(struct udevice *dev, u32 *bootcount)
12 {
13 	struct bootcount_ops *ops = bootcount_get_ops(dev);
14 
15 	assert(ops);
16 	if (!ops->get)
17 		return -ENOSYS;
18 	return ops->get(dev, bootcount);
19 }
20 
21 int dm_bootcount_set(struct udevice *dev, const u32 bootcount)
22 {
23 	struct bootcount_ops *ops = bootcount_get_ops(dev);
24 
25 	assert(ops);
26 	if (!ops->set)
27 		return -ENOSYS;
28 	return ops->set(dev, bootcount);
29 }
30 
31 /* Now implement the generic default functions */
32 void bootcount_store(ulong val)
33 {
34 	struct udevice *dev = NULL;
35 	ofnode node;
36 	const char *propname = "u-boot,bootcount-device";
37 	int ret = -ENODEV;
38 
39 	/*
40 	 * If there's a preferred bootcount device selected by the user (by
41 	 * setting '/chosen/u-boot,bootcount-device' in the DTS), try to use
42 	 * it if available.
43 	 */
44 	node = ofnode_get_chosen_node(propname);
45 	if (ofnode_valid(node))
46 		ret = uclass_get_device_by_ofnode(UCLASS_BOOTCOUNT, node, &dev);
47 
48 	/* If there was no user-selected device, use the first available one */
49 	if (ret)
50 		ret = uclass_get_device(UCLASS_BOOTCOUNT, 0, &dev);
51 
52 	if (dev)
53 		ret = dm_bootcount_set(dev, val);
54 
55 	if (ret)
56 		pr_debug("%s: failed to store 0x%lx\n", __func__, val);
57 }
58 
59 ulong bootcount_load(void)
60 {
61 	struct udevice *dev = NULL;
62 	ofnode node;
63 	const char *propname = "u-boot,bootcount-device";
64 	int ret = -ENODEV;
65 	u32 val;
66 
67 	/*
68 	 * If there's a preferred bootcount device selected by the user (by
69 	 * setting '/chosen/u-boot,bootcount-device' in the DTS), try to use
70 	 * it if available.
71 	 */
72 	node = ofnode_get_chosen_node(propname);
73 	if (ofnode_valid(node))
74 		ret = uclass_get_device_by_ofnode(UCLASS_BOOTCOUNT, node, &dev);
75 
76 	/* If there was no user-selected device, use the first available one */
77 	if (ret)
78 		ret = uclass_get_device(UCLASS_BOOTCOUNT, 0, &dev);
79 
80 	if (dev)
81 		ret = dm_bootcount_get(dev, &val);
82 
83 	if (ret)
84 		pr_debug("%s: failed to load bootcount\n", __func__);
85 
86 	/* Return the 0, if the call to dm_bootcount_get failed */
87 	return ret ? 0 : val;
88 }
89 
90 UCLASS_DRIVER(bootcount) = {
91 	.name		= "bootcount",
92 	.id		= UCLASS_BOOTCOUNT,
93 };
94