1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2019, Linaro Limited
4  */
5 
6 #include <log.h>
7 #include <malloc.h>
8 #include <asm/io.h>
9 #include <common.h>
10 #include <dm.h>
11 #include <dt-bindings/reset/ti-syscon.h>
12 #include <reset-uclass.h>
13 #include <linux/bitops.h>
14 
15 struct hisi_reset_priv {
16 	void __iomem *base;
17 };
18 
hisi_reset_deassert(struct reset_ctl * rst)19 static int hisi_reset_deassert(struct reset_ctl *rst)
20 {
21 	struct hisi_reset_priv *priv = dev_get_priv(rst->dev);
22 	u32 val;
23 
24 	val = readl(priv->base + rst->data);
25 	if (rst->polarity & DEASSERT_SET)
26 		val |= BIT(rst->id);
27 	else
28 		val &= ~BIT(rst->id);
29 	writel(val, priv->base + rst->data);
30 
31 	return 0;
32 }
33 
hisi_reset_assert(struct reset_ctl * rst)34 static int hisi_reset_assert(struct reset_ctl *rst)
35 {
36 	struct hisi_reset_priv *priv = dev_get_priv(rst->dev);
37 	u32 val;
38 
39 	val = readl(priv->base + rst->data);
40 	if (rst->polarity & ASSERT_SET)
41 		val |= BIT(rst->id);
42 	else
43 		val &= ~BIT(rst->id);
44 	writel(val, priv->base + rst->data);
45 
46 	return 0;
47 }
48 
hisi_reset_free(struct reset_ctl * rst)49 static int hisi_reset_free(struct reset_ctl *rst)
50 {
51 	return 0;
52 }
53 
hisi_reset_request(struct reset_ctl * rst)54 static int hisi_reset_request(struct reset_ctl *rst)
55 {
56 	return 0;
57 }
58 
hisi_reset_of_xlate(struct reset_ctl * rst,struct ofnode_phandle_args * args)59 static int hisi_reset_of_xlate(struct reset_ctl *rst,
60 			       struct ofnode_phandle_args *args)
61 {
62 	if (args->args_count != 3) {
63 		debug("Invalid args_count: %d\n", args->args_count);
64 		return -EINVAL;
65 	}
66 
67 	/* Use .data field as register offset and .id field as bit shift */
68 	rst->data = args->args[0];
69 	rst->id = args->args[1];
70 	rst->polarity = args->args[2];
71 
72 	return 0;
73 }
74 
75 static const struct reset_ops hisi_reset_reset_ops = {
76 	.of_xlate = hisi_reset_of_xlate,
77 	.request = hisi_reset_request,
78 	.rfree = hisi_reset_free,
79 	.rst_assert = hisi_reset_assert,
80 	.rst_deassert = hisi_reset_deassert,
81 };
82 
83 static const struct udevice_id hisi_reset_ids[] = {
84 	{ .compatible = "hisilicon,hi3798cv200-reset" },
85 	{ }
86 };
87 
hisi_reset_probe(struct udevice * dev)88 static int hisi_reset_probe(struct udevice *dev)
89 {
90 	struct hisi_reset_priv *priv = dev_get_priv(dev);
91 
92 	priv->base = dev_remap_addr(dev);
93 	if (!priv->base)
94 		return -ENOMEM;
95 
96 	return 0;
97 }
98 
99 U_BOOT_DRIVER(hisi_reset) = {
100 	.name = "hisilicon_reset",
101 	.id = UCLASS_RESET,
102 	.of_match = hisi_reset_ids,
103 	.ops = &hisi_reset_reset_ops,
104 	.probe = hisi_reset_probe,
105 	.priv_auto	= sizeof(struct hisi_reset_priv),
106 };
107