1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
|
Add a watchdog driver for ARM MPcore processors.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -355,6 +355,13 @@ config KS8695_WATCHDOG
Watchdog timer embedded into KS8695 processor. This will reboot your
system when the timeout is reached.
+config MPCORE_WATCHDOG
+ tristate "MPcore watchdog"
+ depends on HAVE_ARM_TWD
+ select WATCHDOG_CORE
+ help
+ Watchdog timer embedded into the MPcore system
+
config HAVE_S3C2410_WATCHDOG
bool
help
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_977_WATCHDOG) += wdt977.o
obj-$(CONFIG_GEMINI_WATCHDOG) += gemini_wdt.o
obj-$(CONFIG_IXP4XX_WATCHDOG) += ixp4xx_wdt.o
obj-$(CONFIG_KS8695_WATCHDOG) += ks8695_wdt.o
+obj-$(CONFIG_MPCORE_WATCHDOG) += mpcore_wdt.o
obj-$(CONFIG_S3C2410_WATCHDOG) += s3c2410_wdt.o
obj-$(CONFIG_SA1100_WATCHDOG) += sa1100_wdt.o
obj-$(CONFIG_SAMA5D4_WATCHDOG) += sama5d4_wdt.o
--- /dev/null
+++ b/drivers/watchdog/mpcore_wdt.c
@@ -0,0 +1,118 @@
+/*
+ * Watchdog driver for ARM MPcore
+ *
+ * Copyright (C) 2017 Felix Fietkau <nbd@nbd.name>
+ */
+
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/watchdog.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <asm/smp_twd.h>
+
+static void __iomem *wdt_base;
+static int wdt_timeout = 60;
+
+static int mpcore_wdt_keepalive(struct watchdog_device *wdd)
+{
+ static int perturb;
+ u32 count;
+
+ count = (twd_timer_get_rate() / 256) * wdt_timeout;
+
+ /* Reload register needs a different value on each refresh */
+ count += perturb;
+ perturb = !perturb;
+
+ iowrite32(count, wdt_base + TWD_WDOG_LOAD);
+
+ return 0;
+}
+
+static int mpcore_wdt_start(struct watchdog_device *wdd)
+{
+ mpcore_wdt_keepalive(wdd);
+
+ /* prescale = 256, mode = 1, enable = 1 */
+ iowrite32(0x0000FF09, wdt_base + TWD_WDOG_CONTROL);
+
+ return 0;
+}
+
+static int mpcore_wdt_stop(struct watchdog_device *wdd)
+{
+ iowrite32(0x12345678, wdt_base + TWD_WDOG_DISABLE);
+ iowrite32(0x87654321, wdt_base + TWD_WDOG_DISABLE);
+ iowrite32(0x0, wdt_base + TWD_WDOG_CONTROL);
+
+ return 0;
+}
+
+static int mpcore_wdt_set_timeout(struct watchdog_device *wdd,
+ unsigned int timeout)
+{
+ mpcore_wdt_stop(wdd);
+ wdt_timeout = timeout;
+ mpcore_wdt_start(wdd);
+
+ return 0;
+}
+
+static const struct watchdog_info mpcore_wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "MPcore Watchdog",
+};
+
+static const struct watchdog_ops mpcore_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = mpcore_wdt_start,
+ .stop = mpcore_wdt_stop,
+ .ping = mpcore_wdt_keepalive,
+ .set_timeout = mpcore_wdt_set_timeout,
+};
+
+static struct watchdog_device mpcore_wdt = {
+ .info = &mpcore_wdt_info,
+ .ops = &mpcore_wdt_ops,
+ .min_timeout = 1,
+ .max_timeout = 65535,
+};
+
+static int mpcore_wdt_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ unsigned long rate = twd_timer_get_rate();
+
+ pr_info("MPCore WD init. clockrate: %u prescaler: %u countrate: %u timeout: %us\n", rate, 256, rate / 256, wdt_timeout);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ wdt_base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(wdt_base))
+ return PTR_ERR(wdt_base);
+
+ watchdog_register_device(&mpcore_wdt);
+ return 0;
+}
+
+static int mpcore_wdt_remove(struct platform_device *dev)
+{
+ watchdog_unregister_device(&mpcore_wdt);
+ return 0;
+}
+
+static struct platform_driver mpcore_wdt_driver = {
+ .probe = mpcore_wdt_probe,
+ .remove = mpcore_wdt_remove,
+ .driver = {
+ .name = "mpcore_wdt",
+ },
+};
+
+module_platform_driver(mpcore_wdt_driver);
+MODULE_AUTHOR("Felix Fietkau <nbd@nbd.name>");
+MODULE_LICENSE("GPL");
--- a/arch/arm/include/asm/smp_twd.h
+++ b/arch/arm/include/asm/smp_twd.h
@@ -34,5 +34,6 @@ struct twd_local_timer name __initdata =
};
int twd_local_timer_register(struct twd_local_timer *);
+unsigned long twd_timer_get_rate(void);
#endif
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -15,6 +15,7 @@
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
+#include <linux/export.h>
#include <linux/smp.h>
#include <linux/jiffies.h>
#include <linux/clockchips.h>
@@ -380,6 +381,14 @@ int __init twd_local_timer_register(stru
return twd_local_timer_common_register(NULL);
}
+/* Needed by mpcore_wdt */
+unsigned long twd_timer_get_rate(void)
+{
+ return twd_timer_rate;
+}
+EXPORT_SYMBOL_GPL(twd_timer_get_rate);
+
+
#ifdef CONFIG_OF
static int __init twd_local_timer_of_register(struct device_node *np)
{
|