1 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
2 /*
3 * Copyright (C) 2018 Amarula Solutions.
4 * Author: Jagan Teki <jagan@amarulasolutions.com>
5 */
6
7 #include <common.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <reset-uclass.h>
11 #include <asm/io.h>
12 #include <dm/lists.h>
13 #include <linux/log2.h>
14 #include <asm/arch/ccu.h>
15
16 struct sunxi_reset_priv {
17 void *base;
18 ulong count;
19 const struct ccu_desc *desc;
20 };
21
priv_to_reset(struct sunxi_reset_priv * priv,unsigned long id)22 static const struct ccu_reset *priv_to_reset(struct sunxi_reset_priv *priv,
23 unsigned long id)
24 {
25 return &priv->desc->resets[id];
26 }
27
sunxi_reset_request(struct reset_ctl * reset_ctl)28 static int sunxi_reset_request(struct reset_ctl *reset_ctl)
29 {
30 struct sunxi_reset_priv *priv = dev_get_priv(reset_ctl->dev);
31
32 debug("%s: (RST#%ld)\n", __func__, reset_ctl->id);
33
34 if (reset_ctl->id >= priv->count)
35 return -EINVAL;
36
37 return 0;
38 }
39
sunxi_reset_free(struct reset_ctl * reset_ctl)40 static int sunxi_reset_free(struct reset_ctl *reset_ctl)
41 {
42 debug("%s: (RST#%ld)\n", __func__, reset_ctl->id);
43
44 return 0;
45 }
46
sunxi_set_reset(struct reset_ctl * reset_ctl,bool on)47 static int sunxi_set_reset(struct reset_ctl *reset_ctl, bool on)
48 {
49 struct sunxi_reset_priv *priv = dev_get_priv(reset_ctl->dev);
50 const struct ccu_reset *reset = priv_to_reset(priv, reset_ctl->id);
51 u32 reg;
52
53 if (!(reset->flags & CCU_RST_F_IS_VALID)) {
54 printf("%s: (RST#%ld) unhandled\n", __func__, reset_ctl->id);
55 return 0;
56 }
57
58 debug("%s: (RST#%ld) off#0x%x, BIT(%d)\n", __func__,
59 reset_ctl->id, reset->off, ilog2(reset->bit));
60
61 reg = readl(priv->base + reset->off);
62 if (on)
63 reg |= reset->bit;
64 else
65 reg &= ~reset->bit;
66
67 writel(reg, priv->base + reset->off);
68
69 return 0;
70 }
71
sunxi_reset_assert(struct reset_ctl * reset_ctl)72 static int sunxi_reset_assert(struct reset_ctl *reset_ctl)
73 {
74 return sunxi_set_reset(reset_ctl, false);
75 }
76
sunxi_reset_deassert(struct reset_ctl * reset_ctl)77 static int sunxi_reset_deassert(struct reset_ctl *reset_ctl)
78 {
79 return sunxi_set_reset(reset_ctl, true);
80 }
81
82 struct reset_ops sunxi_reset_ops = {
83 .request = sunxi_reset_request,
84 .free = sunxi_reset_free,
85 .rst_assert = sunxi_reset_assert,
86 .rst_deassert = sunxi_reset_deassert,
87 };
88
sunxi_reset_probe(struct udevice * dev)89 static int sunxi_reset_probe(struct udevice *dev)
90 {
91 struct sunxi_reset_priv *priv = dev_get_priv(dev);
92
93 priv->base = dev_read_addr_ptr(dev);
94
95 return 0;
96 }
97
sunxi_reset_bind(struct udevice * dev,ulong count)98 int sunxi_reset_bind(struct udevice *dev, ulong count)
99 {
100 struct udevice *rst_dev;
101 struct sunxi_reset_priv *priv;
102 int ret;
103
104 ret = device_bind_driver_to_node(dev, "sunxi_reset", "reset",
105 dev_ofnode(dev), &rst_dev);
106 if (ret) {
107 debug("failed to bind sunxi_reset driver (ret=%d)\n", ret);
108 return ret;
109 }
110 priv = malloc(sizeof(struct sunxi_reset_priv));
111 priv->count = count;
112 priv->desc = (const struct ccu_desc *)dev_get_driver_data(dev);
113 rst_dev->priv = priv;
114
115 return 0;
116 }
117
118 U_BOOT_DRIVER(sunxi_reset) = {
119 .name = "sunxi_reset",
120 .id = UCLASS_RESET,
121 .ops = &sunxi_reset_ops,
122 .probe = sunxi_reset_probe,
123 .priv_auto_alloc_size = sizeof(struct sunxi_reset_priv),
124 };
125