1 /*
2 * drivers/watchdog/orion_wdt.c
3 *
4 * Watchdog driver for Orion/Kirkwood processors
5 *
6 * Authors: Tomas Hlavacek <tmshlvck@gmail.com>
7 * Sylver Bruneau <sylver.bruneau@googlemail.com>
8 * Marek Behun <marek.behun@nic.cz>
9 *
10 * This file is licensed under the terms of the GNU General Public
11 * License version 2. This program is licensed "as is" without any
12 * warranty of any kind, whether express or implied.
13 */
14
15 #include <common.h>
16 #include <dm.h>
17 #include <wdt.h>
18 #include <asm/io.h>
19 #include <asm/arch/cpu.h>
20 #include <asm/arch/soc.h>
21
22 DECLARE_GLOBAL_DATA_PTR;
23
24 struct orion_wdt_priv {
25 void __iomem *reg;
26 int wdt_counter_offset;
27 void __iomem *rstout;
28 void __iomem *rstout_mask;
29 u32 timeout;
30 };
31
32 #define RSTOUT_ENABLE_BIT BIT(8)
33 #define RSTOUT_MASK_BIT BIT(10)
34 #define WDT_ENABLE_BIT BIT(8)
35
36 #define TIMER_CTRL 0x0000
37 #define TIMER_A370_STATUS 0x04
38
39 #define WDT_AXP_FIXED_ENABLE_BIT BIT(10)
40 #define WDT_A370_EXPIRED BIT(31)
41
orion_wdt_reset(struct udevice * dev)42 static int orion_wdt_reset(struct udevice *dev)
43 {
44 struct orion_wdt_priv *priv = dev_get_priv(dev);
45
46 /* Reload watchdog duration */
47 writel(priv->timeout, priv->reg + priv->wdt_counter_offset);
48
49 return 0;
50 }
51
orion_wdt_start(struct udevice * dev,u64 timeout,ulong flags)52 static int orion_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
53 {
54 struct orion_wdt_priv *priv = dev_get_priv(dev);
55 u32 reg;
56
57 priv->timeout = (u32) timeout;
58
59 /* Enable the fixed watchdog clock input */
60 reg = readl(priv->reg + TIMER_CTRL);
61 reg |= WDT_AXP_FIXED_ENABLE_BIT;
62 writel(reg, priv->reg + TIMER_CTRL);
63
64 /* Set watchdog duration */
65 writel(priv->timeout, priv->reg + priv->wdt_counter_offset);
66
67 /* Clear the watchdog expiration bit */
68 reg = readl(priv->reg + TIMER_A370_STATUS);
69 reg &= ~WDT_A370_EXPIRED;
70 writel(reg, priv->reg + TIMER_A370_STATUS);
71
72 /* Enable watchdog timer */
73 reg = readl(priv->reg + TIMER_CTRL);
74 reg |= WDT_ENABLE_BIT;
75 writel(reg, priv->reg + TIMER_CTRL);
76
77 /* Enable reset on watchdog */
78 reg = readl(priv->rstout);
79 reg |= RSTOUT_ENABLE_BIT;
80 writel(reg, priv->rstout);
81
82 reg = readl(priv->rstout_mask);
83 reg &= ~RSTOUT_MASK_BIT;
84 writel(reg, priv->rstout_mask);
85
86 return 0;
87 }
88
orion_wdt_stop(struct udevice * dev)89 static int orion_wdt_stop(struct udevice *dev)
90 {
91 struct orion_wdt_priv *priv = dev_get_priv(dev);
92 u32 reg;
93
94 /* Disable reset on watchdog */
95 reg = readl(priv->rstout_mask);
96 reg |= RSTOUT_MASK_BIT;
97 writel(reg, priv->rstout_mask);
98
99 reg = readl(priv->rstout);
100 reg &= ~RSTOUT_ENABLE_BIT;
101 writel(reg, priv->rstout);
102
103 /* Disable watchdog timer */
104 reg = readl(priv->reg + TIMER_CTRL);
105 reg &= ~WDT_ENABLE_BIT;
106 writel(reg, priv->reg + TIMER_CTRL);
107
108 return 0;
109 }
110
save_reg_from_ofdata(struct udevice * dev,int index,void __iomem ** reg,int * offset)111 static inline bool save_reg_from_ofdata(struct udevice *dev, int index,
112 void __iomem **reg, int *offset)
113 {
114 fdt_addr_t addr;
115 fdt_size_t off;
116
117 addr = fdtdec_get_addr_size_auto_noparent(
118 gd->fdt_blob, dev_of_offset(dev), "reg", index, &off, true);
119
120 if (addr == FDT_ADDR_T_NONE)
121 return false;
122
123 *reg = (void __iomem *) addr;
124 if (offset)
125 *offset = off;
126
127 return true;
128 }
129
orion_wdt_ofdata_to_platdata(struct udevice * dev)130 static int orion_wdt_ofdata_to_platdata(struct udevice *dev)
131 {
132 struct orion_wdt_priv *priv = dev_get_priv(dev);
133
134 if (!save_reg_from_ofdata(dev, 0, &priv->reg,
135 &priv->wdt_counter_offset))
136 goto err;
137
138 if (!save_reg_from_ofdata(dev, 1, &priv->rstout, NULL))
139 goto err;
140
141 if (!save_reg_from_ofdata(dev, 2, &priv->rstout_mask, NULL))
142 goto err;
143
144 return 0;
145 err:
146 debug("%s: Could not determine Orion wdt IO addresses\n", __func__);
147 return -ENXIO;
148 }
149
orion_wdt_probe(struct udevice * dev)150 static int orion_wdt_probe(struct udevice *dev)
151 {
152 debug("%s: Probing wdt%u\n", __func__, dev->seq);
153 orion_wdt_stop(dev);
154
155 return 0;
156 }
157
158 static const struct wdt_ops orion_wdt_ops = {
159 .start = orion_wdt_start,
160 .reset = orion_wdt_reset,
161 .stop = orion_wdt_stop,
162 };
163
164 static const struct udevice_id orion_wdt_ids[] = {
165 { .compatible = "marvell,armada-380-wdt" },
166 {}
167 };
168
169 U_BOOT_DRIVER(orion_wdt) = {
170 .name = "orion_wdt",
171 .id = UCLASS_WDT,
172 .of_match = orion_wdt_ids,
173 .probe = orion_wdt_probe,
174 .priv_auto_alloc_size = sizeof(struct orion_wdt_priv),
175 .ofdata_to_platdata = orion_wdt_ofdata_to_platdata,
176 .ops = &orion_wdt_ops,
177 };
178