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1/*
2 * drivers/watchdog/orion_wdt.c
3 *
4 * Watchdog driver for Orion/Kirkwood processors
5 *
6 * Author: Sylver Bruneau <sylver.bruneau@googlemail.com>
7 *
8 * This file is licensed under the terms of the GNU General Public
9 * License version 2. This program is licensed "as is" without any
10 * warranty of any kind, whether express or implied.
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/module.h>
16#include <linux/moduleparam.h>
17#include <linux/types.h>
18#include <linux/kernel.h>
19#include <linux/fs.h>
20#include <linux/miscdevice.h>
21#include <linux/platform_device.h>
22#include <linux/watchdog.h>
23#include <linux/init.h>
24#include <linux/uaccess.h>
25#include <linux/io.h>
26#include <linux/spinlock.h>
27#include <linux/clk.h>
28#include <mach/bridge-regs.h>
29
30/*
31 * Watchdog timer block registers.
32 */
33#define TIMER_CTRL 0x0000
34#define WDT_EN 0x0010
35#define WDT_VAL 0x0024
36
37#define WDT_MAX_CYCLE_COUNT 0xffffffff
38#define WDT_IN_USE 0
39#define WDT_OK_TO_CLOSE 1
40
41static bool nowayout = WATCHDOG_NOWAYOUT;
42static int heartbeat = -1; /* module parameter (seconds) */
43static unsigned int wdt_max_duration; /* (seconds) */
44static struct clk *clk;
45static unsigned int wdt_tclk;
46static void __iomem *wdt_reg;
47static unsigned long wdt_status;
48static DEFINE_SPINLOCK(wdt_lock);
49
50static void orion_wdt_ping(void)
51{
52 spin_lock(&wdt_lock);
53
54 /* Reload watchdog duration */
55 writel(wdt_tclk * heartbeat, wdt_reg + WDT_VAL);
56
57 spin_unlock(&wdt_lock);
58}
59
60static void orion_wdt_enable(void)
61{
62 u32 reg;
63
64 spin_lock(&wdt_lock);
65
66 /* Set watchdog duration */
67 writel(wdt_tclk * heartbeat, wdt_reg + WDT_VAL);
68
69 /* Clear watchdog timer interrupt */
70 reg = readl(BRIDGE_CAUSE);
71 reg &= ~WDT_INT_REQ;
72 writel(reg, BRIDGE_CAUSE);
73
74 /* Enable watchdog timer */
75 reg = readl(wdt_reg + TIMER_CTRL);
76 reg |= WDT_EN;
77 writel(reg, wdt_reg + TIMER_CTRL);
78
79 /* Enable reset on watchdog */
80 reg = readl(RSTOUTn_MASK);
81 reg |= WDT_RESET_OUT_EN;
82 writel(reg, RSTOUTn_MASK);
83
84 spin_unlock(&wdt_lock);
85}
86
87static void orion_wdt_disable(void)
88{
89 u32 reg;
90
91 spin_lock(&wdt_lock);
92
93 /* Disable reset on watchdog */
94 reg = readl(RSTOUTn_MASK);
95 reg &= ~WDT_RESET_OUT_EN;
96 writel(reg, RSTOUTn_MASK);
97
98 /* Disable watchdog timer */
99 reg = readl(wdt_reg + TIMER_CTRL);
100 reg &= ~WDT_EN;
101 writel(reg, wdt_reg + TIMER_CTRL);
102
103 spin_unlock(&wdt_lock);
104}
105
106static int orion_wdt_get_timeleft(int *time_left)
107{
108 spin_lock(&wdt_lock);
109 *time_left = readl(wdt_reg + WDT_VAL) / wdt_tclk;
110 spin_unlock(&wdt_lock);
111 return 0;
112}
113
114static int orion_wdt_open(struct inode *inode, struct file *file)
115{
116 if (test_and_set_bit(WDT_IN_USE, &wdt_status))
117 return -EBUSY;
118 clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
119 orion_wdt_enable();
120 return nonseekable_open(inode, file);
121}
122
123static ssize_t orion_wdt_write(struct file *file, const char *data,
124 size_t len, loff_t *ppos)
125{
126 if (len) {
127 if (!nowayout) {
128 size_t i;
129
130 clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
131 for (i = 0; i != len; i++) {
132 char c;
133
134 if (get_user(c, data + i))
135 return -EFAULT;
136 if (c == 'V')
137 set_bit(WDT_OK_TO_CLOSE, &wdt_status);
138 }
139 }
140 orion_wdt_ping();
141 }
142 return len;
143}
144
145static int orion_wdt_settimeout(int new_time)
146{
147 if ((new_time <= 0) || (new_time > wdt_max_duration))
148 return -EINVAL;
149
150 /* Set new watchdog time to be used when
151 * orion_wdt_enable() or orion_wdt_ping() is called. */
152 heartbeat = new_time;
153 return 0;
154}
155
156static const struct watchdog_info ident = {
157 .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT |
158 WDIOF_KEEPALIVEPING,
159 .identity = "Orion Watchdog",
160};
161
162static long orion_wdt_ioctl(struct file *file, unsigned int cmd,
163 unsigned long arg)
164{
165 int ret = -ENOTTY;
166 int time;
167
168 switch (cmd) {
169 case WDIOC_GETSUPPORT:
170 ret = copy_to_user((struct watchdog_info *)arg, &ident,
171 sizeof(ident)) ? -EFAULT : 0;
172 break;
173
174 case WDIOC_GETSTATUS:
175 case WDIOC_GETBOOTSTATUS:
176 ret = put_user(0, (int *)arg);
177 break;
178
179 case WDIOC_KEEPALIVE:
180 orion_wdt_ping();
181 ret = 0;
182 break;
183
184 case WDIOC_SETTIMEOUT:
185 ret = get_user(time, (int *)arg);
186 if (ret)
187 break;
188
189 if (orion_wdt_settimeout(time)) {
190 ret = -EINVAL;
191 break;
192 }
193 orion_wdt_ping();
194 /* Fall through */
195
196 case WDIOC_GETTIMEOUT:
197 ret = put_user(heartbeat, (int *)arg);
198 break;
199
200 case WDIOC_GETTIMELEFT:
201 if (orion_wdt_get_timeleft(&time)) {
202 ret = -EINVAL;
203 break;
204 }
205 ret = put_user(time, (int *)arg);
206 break;
207 }
208 return ret;
209}
210
211static int orion_wdt_release(struct inode *inode, struct file *file)
212{
213 if (test_bit(WDT_OK_TO_CLOSE, &wdt_status))
214 orion_wdt_disable();
215 else
216 pr_crit("Device closed unexpectedly - timer will not stop\n");
217 clear_bit(WDT_IN_USE, &wdt_status);
218 clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
219
220 return 0;
221}
222
223
224static const struct file_operations orion_wdt_fops = {
225 .owner = THIS_MODULE,
226 .llseek = no_llseek,
227 .write = orion_wdt_write,
228 .unlocked_ioctl = orion_wdt_ioctl,
229 .open = orion_wdt_open,
230 .release = orion_wdt_release,
231};
232
233static struct miscdevice orion_wdt_miscdev = {
234 .minor = WATCHDOG_MINOR,
235 .name = "watchdog",
236 .fops = &orion_wdt_fops,
237};
238
239static int __devinit orion_wdt_probe(struct platform_device *pdev)
240{
241 struct resource *res;
242 int ret;
243
244 clk = clk_get(&pdev->dev, NULL);
245 if (IS_ERR(clk)) {
246 printk(KERN_ERR "Orion Watchdog missing clock\n");
247 return -ENODEV;
248 }
249 clk_prepare_enable(clk);
250 wdt_tclk = clk_get_rate(clk);
251
252 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
253
254 wdt_reg = ioremap(res->start, resource_size(res));
255
256 if (orion_wdt_miscdev.parent)
257 return -EBUSY;
258 orion_wdt_miscdev.parent = &pdev->dev;
259
260 wdt_max_duration = WDT_MAX_CYCLE_COUNT / wdt_tclk;
261 if (orion_wdt_settimeout(heartbeat))
262 heartbeat = wdt_max_duration;
263
264 ret = misc_register(&orion_wdt_miscdev);
265 if (ret)
266 return ret;
267
268 pr_info("Initial timeout %d sec%s\n",
269 heartbeat, nowayout ? ", nowayout" : "");
270 return 0;
271}
272
273static int __devexit orion_wdt_remove(struct platform_device *pdev)
274{
275 int ret;
276
277 if (test_bit(WDT_IN_USE, &wdt_status)) {
278 orion_wdt_disable();
279 clear_bit(WDT_IN_USE, &wdt_status);
280 }
281
282 ret = misc_deregister(&orion_wdt_miscdev);
283 if (!ret)
284 orion_wdt_miscdev.parent = NULL;
285
286 clk_disable_unprepare(clk);
287 clk_put(clk);
288
289 return ret;
290}
291
292static void orion_wdt_shutdown(struct platform_device *pdev)
293{
294 if (test_bit(WDT_IN_USE, &wdt_status))
295 orion_wdt_disable();
296}
297
298static struct platform_driver orion_wdt_driver = {
299 .probe = orion_wdt_probe,
300 .remove = __devexit_p(orion_wdt_remove),
301 .shutdown = orion_wdt_shutdown,
302 .driver = {
303 .owner = THIS_MODULE,
304 .name = "orion_wdt",
305 },
306};
307
308module_platform_driver(orion_wdt_driver);
309
310MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
311MODULE_DESCRIPTION("Orion Processor Watchdog");
312
313module_param(heartbeat, int, 0);
314MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
315
316module_param(nowayout, bool, 0);
317MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
318 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
319
320MODULE_LICENSE("GPL");
321MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
1/*
2 * drivers/watchdog/orion_wdt.c
3 *
4 * Watchdog driver for Orion/Kirkwood processors
5 *
6 * Author: Sylver Bruneau <sylver.bruneau@googlemail.com>
7 *
8 * This file is licensed under the terms of the GNU General Public
9 * License version 2. This program is licensed "as is" without any
10 * warranty of any kind, whether express or implied.
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/module.h>
16#include <linux/moduleparam.h>
17#include <linux/types.h>
18#include <linux/kernel.h>
19#include <linux/platform_device.h>
20#include <linux/watchdog.h>
21#include <linux/interrupt.h>
22#include <linux/io.h>
23#include <linux/clk.h>
24#include <linux/err.h>
25#include <linux/of.h>
26#include <linux/of_device.h>
27
28/* RSTOUT mask register physical address for Orion5x, Kirkwood and Dove */
29#define ORION_RSTOUT_MASK_OFFSET 0x20108
30
31/* Internal registers can be configured at any 1 MiB aligned address */
32#define INTERNAL_REGS_MASK ~(SZ_1M - 1)
33
34/*
35 * Watchdog timer block registers.
36 */
37#define TIMER_CTRL 0x0000
38#define TIMER1_FIXED_ENABLE_BIT BIT(12)
39#define WDT_AXP_FIXED_ENABLE_BIT BIT(10)
40#define TIMER1_ENABLE_BIT BIT(2)
41
42#define TIMER_A370_STATUS 0x0004
43#define WDT_A370_EXPIRED BIT(31)
44#define TIMER1_STATUS_BIT BIT(8)
45
46#define TIMER1_VAL_OFF 0x001c
47
48#define WDT_MAX_CYCLE_COUNT 0xffffffff
49
50#define WDT_A370_RATIO_MASK(v) ((v) << 16)
51#define WDT_A370_RATIO_SHIFT 5
52#define WDT_A370_RATIO (1 << WDT_A370_RATIO_SHIFT)
53
54static bool nowayout = WATCHDOG_NOWAYOUT;
55static int heartbeat; /* module parameter (seconds) */
56
57struct orion_watchdog;
58
59struct orion_watchdog_data {
60 int wdt_counter_offset;
61 int wdt_enable_bit;
62 int rstout_enable_bit;
63 int rstout_mask_bit;
64 int (*clock_init)(struct platform_device *,
65 struct orion_watchdog *);
66 int (*enabled)(struct orion_watchdog *);
67 int (*start)(struct watchdog_device *);
68 int (*stop)(struct watchdog_device *);
69};
70
71struct orion_watchdog {
72 struct watchdog_device wdt;
73 void __iomem *reg;
74 void __iomem *rstout;
75 void __iomem *rstout_mask;
76 unsigned long clk_rate;
77 struct clk *clk;
78 const struct orion_watchdog_data *data;
79};
80
81static int orion_wdt_clock_init(struct platform_device *pdev,
82 struct orion_watchdog *dev)
83{
84 int ret;
85
86 dev->clk = clk_get(&pdev->dev, NULL);
87 if (IS_ERR(dev->clk))
88 return PTR_ERR(dev->clk);
89 ret = clk_prepare_enable(dev->clk);
90 if (ret) {
91 clk_put(dev->clk);
92 return ret;
93 }
94
95 dev->clk_rate = clk_get_rate(dev->clk);
96 return 0;
97}
98
99static int armada370_wdt_clock_init(struct platform_device *pdev,
100 struct orion_watchdog *dev)
101{
102 int ret;
103
104 dev->clk = clk_get(&pdev->dev, NULL);
105 if (IS_ERR(dev->clk))
106 return PTR_ERR(dev->clk);
107 ret = clk_prepare_enable(dev->clk);
108 if (ret) {
109 clk_put(dev->clk);
110 return ret;
111 }
112
113 /* Setup watchdog input clock */
114 atomic_io_modify(dev->reg + TIMER_CTRL,
115 WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT),
116 WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT));
117
118 dev->clk_rate = clk_get_rate(dev->clk) / WDT_A370_RATIO;
119 return 0;
120}
121
122static int armada375_wdt_clock_init(struct platform_device *pdev,
123 struct orion_watchdog *dev)
124{
125 int ret;
126
127 dev->clk = of_clk_get_by_name(pdev->dev.of_node, "fixed");
128 if (!IS_ERR(dev->clk)) {
129 ret = clk_prepare_enable(dev->clk);
130 if (ret) {
131 clk_put(dev->clk);
132 return ret;
133 }
134
135 atomic_io_modify(dev->reg + TIMER_CTRL,
136 WDT_AXP_FIXED_ENABLE_BIT,
137 WDT_AXP_FIXED_ENABLE_BIT);
138 dev->clk_rate = clk_get_rate(dev->clk);
139
140 return 0;
141 }
142
143 /* Mandatory fallback for proper devicetree backward compatibility */
144 dev->clk = clk_get(&pdev->dev, NULL);
145 if (IS_ERR(dev->clk))
146 return PTR_ERR(dev->clk);
147
148 ret = clk_prepare_enable(dev->clk);
149 if (ret) {
150 clk_put(dev->clk);
151 return ret;
152 }
153
154 atomic_io_modify(dev->reg + TIMER_CTRL,
155 WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT),
156 WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT));
157 dev->clk_rate = clk_get_rate(dev->clk) / WDT_A370_RATIO;
158
159 return 0;
160}
161
162static int armadaxp_wdt_clock_init(struct platform_device *pdev,
163 struct orion_watchdog *dev)
164{
165 int ret;
166 u32 val;
167
168 dev->clk = of_clk_get_by_name(pdev->dev.of_node, "fixed");
169 if (IS_ERR(dev->clk))
170 return PTR_ERR(dev->clk);
171 ret = clk_prepare_enable(dev->clk);
172 if (ret) {
173 clk_put(dev->clk);
174 return ret;
175 }
176
177 /* Fix the wdt and timer1 clock frequency to 25MHz */
178 val = WDT_AXP_FIXED_ENABLE_BIT | TIMER1_FIXED_ENABLE_BIT;
179 atomic_io_modify(dev->reg + TIMER_CTRL, val, val);
180
181 dev->clk_rate = clk_get_rate(dev->clk);
182 return 0;
183}
184
185static int orion_wdt_ping(struct watchdog_device *wdt_dev)
186{
187 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
188 /* Reload watchdog duration */
189 writel(dev->clk_rate * wdt_dev->timeout,
190 dev->reg + dev->data->wdt_counter_offset);
191 if (dev->wdt.info->options & WDIOF_PRETIMEOUT)
192 writel(dev->clk_rate * (wdt_dev->timeout - wdt_dev->pretimeout),
193 dev->reg + TIMER1_VAL_OFF);
194
195 return 0;
196}
197
198static int armada375_start(struct watchdog_device *wdt_dev)
199{
200 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
201 u32 reg;
202
203 /* Set watchdog duration */
204 writel(dev->clk_rate * wdt_dev->timeout,
205 dev->reg + dev->data->wdt_counter_offset);
206 if (dev->wdt.info->options & WDIOF_PRETIMEOUT)
207 writel(dev->clk_rate * (wdt_dev->timeout - wdt_dev->pretimeout),
208 dev->reg + TIMER1_VAL_OFF);
209
210 /* Clear the watchdog expiration bit */
211 atomic_io_modify(dev->reg + TIMER_A370_STATUS, WDT_A370_EXPIRED, 0);
212
213 /* Enable watchdog timer */
214 reg = dev->data->wdt_enable_bit;
215 if (dev->wdt.info->options & WDIOF_PRETIMEOUT)
216 reg |= TIMER1_ENABLE_BIT;
217 atomic_io_modify(dev->reg + TIMER_CTRL, reg, reg);
218
219 /* Enable reset on watchdog */
220 reg = readl(dev->rstout);
221 reg |= dev->data->rstout_enable_bit;
222 writel(reg, dev->rstout);
223
224 atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit, 0);
225 return 0;
226}
227
228static int armada370_start(struct watchdog_device *wdt_dev)
229{
230 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
231 u32 reg;
232
233 /* Set watchdog duration */
234 writel(dev->clk_rate * wdt_dev->timeout,
235 dev->reg + dev->data->wdt_counter_offset);
236
237 /* Clear the watchdog expiration bit */
238 atomic_io_modify(dev->reg + TIMER_A370_STATUS, WDT_A370_EXPIRED, 0);
239
240 /* Enable watchdog timer */
241 reg = dev->data->wdt_enable_bit;
242 if (dev->wdt.info->options & WDIOF_PRETIMEOUT)
243 reg |= TIMER1_ENABLE_BIT;
244 atomic_io_modify(dev->reg + TIMER_CTRL, reg, reg);
245
246 /* Enable reset on watchdog */
247 reg = readl(dev->rstout);
248 reg |= dev->data->rstout_enable_bit;
249 writel(reg, dev->rstout);
250 return 0;
251}
252
253static int orion_start(struct watchdog_device *wdt_dev)
254{
255 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
256
257 /* Set watchdog duration */
258 writel(dev->clk_rate * wdt_dev->timeout,
259 dev->reg + dev->data->wdt_counter_offset);
260
261 /* Enable watchdog timer */
262 atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
263 dev->data->wdt_enable_bit);
264
265 /* Enable reset on watchdog */
266 atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit,
267 dev->data->rstout_enable_bit);
268
269 return 0;
270}
271
272static int orion_wdt_start(struct watchdog_device *wdt_dev)
273{
274 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
275
276 /* There are some per-SoC quirks to handle */
277 return dev->data->start(wdt_dev);
278}
279
280static int orion_stop(struct watchdog_device *wdt_dev)
281{
282 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
283
284 /* Disable reset on watchdog */
285 atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit, 0);
286
287 /* Disable watchdog timer */
288 atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
289
290 return 0;
291}
292
293static int armada375_stop(struct watchdog_device *wdt_dev)
294{
295 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
296 u32 reg, mask;
297
298 /* Disable reset on watchdog */
299 atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit,
300 dev->data->rstout_mask_bit);
301 reg = readl(dev->rstout);
302 reg &= ~dev->data->rstout_enable_bit;
303 writel(reg, dev->rstout);
304
305 /* Disable watchdog timer */
306 mask = dev->data->wdt_enable_bit;
307 if (wdt_dev->info->options & WDIOF_PRETIMEOUT)
308 mask |= TIMER1_ENABLE_BIT;
309 atomic_io_modify(dev->reg + TIMER_CTRL, mask, 0);
310
311 return 0;
312}
313
314static int armada370_stop(struct watchdog_device *wdt_dev)
315{
316 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
317 u32 reg, mask;
318
319 /* Disable reset on watchdog */
320 reg = readl(dev->rstout);
321 reg &= ~dev->data->rstout_enable_bit;
322 writel(reg, dev->rstout);
323
324 /* Disable watchdog timer */
325 mask = dev->data->wdt_enable_bit;
326 if (wdt_dev->info->options & WDIOF_PRETIMEOUT)
327 mask |= TIMER1_ENABLE_BIT;
328 atomic_io_modify(dev->reg + TIMER_CTRL, mask, 0);
329
330 return 0;
331}
332
333static int orion_wdt_stop(struct watchdog_device *wdt_dev)
334{
335 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
336
337 return dev->data->stop(wdt_dev);
338}
339
340static int orion_enabled(struct orion_watchdog *dev)
341{
342 bool enabled, running;
343
344 enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
345 running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
346
347 return enabled && running;
348}
349
350static int armada375_enabled(struct orion_watchdog *dev)
351{
352 bool masked, enabled, running;
353
354 masked = readl(dev->rstout_mask) & dev->data->rstout_mask_bit;
355 enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
356 running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
357
358 return !masked && enabled && running;
359}
360
361static int orion_wdt_enabled(struct watchdog_device *wdt_dev)
362{
363 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
364
365 return dev->data->enabled(dev);
366}
367
368static unsigned int orion_wdt_get_timeleft(struct watchdog_device *wdt_dev)
369{
370 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
371 return readl(dev->reg + dev->data->wdt_counter_offset) / dev->clk_rate;
372}
373
374static struct watchdog_info orion_wdt_info = {
375 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
376 .identity = "Orion Watchdog",
377};
378
379static const struct watchdog_ops orion_wdt_ops = {
380 .owner = THIS_MODULE,
381 .start = orion_wdt_start,
382 .stop = orion_wdt_stop,
383 .ping = orion_wdt_ping,
384 .get_timeleft = orion_wdt_get_timeleft,
385};
386
387static irqreturn_t orion_wdt_irq(int irq, void *devid)
388{
389 panic("Watchdog Timeout");
390 return IRQ_HANDLED;
391}
392
393static irqreturn_t orion_wdt_pre_irq(int irq, void *devid)
394{
395 struct orion_watchdog *dev = devid;
396
397 atomic_io_modify(dev->reg + TIMER_A370_STATUS,
398 TIMER1_STATUS_BIT, 0);
399 watchdog_notify_pretimeout(&dev->wdt);
400 return IRQ_HANDLED;
401}
402
403/*
404 * The original devicetree binding for this driver specified only
405 * one memory resource, so in order to keep DT backwards compatibility
406 * we try to fallback to a hardcoded register address, if the resource
407 * is missing from the devicetree.
408 */
409static void __iomem *orion_wdt_ioremap_rstout(struct platform_device *pdev,
410 phys_addr_t internal_regs)
411{
412 struct resource *res;
413 phys_addr_t rstout;
414
415 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
416 if (res)
417 return devm_ioremap(&pdev->dev, res->start,
418 resource_size(res));
419
420 rstout = internal_regs + ORION_RSTOUT_MASK_OFFSET;
421
422 WARN(1, FW_BUG "falling back to hardcoded RSTOUT reg %pa\n", &rstout);
423 return devm_ioremap(&pdev->dev, rstout, 0x4);
424}
425
426static const struct orion_watchdog_data orion_data = {
427 .rstout_enable_bit = BIT(1),
428 .wdt_enable_bit = BIT(4),
429 .wdt_counter_offset = 0x24,
430 .clock_init = orion_wdt_clock_init,
431 .enabled = orion_enabled,
432 .start = orion_start,
433 .stop = orion_stop,
434};
435
436static const struct orion_watchdog_data armada370_data = {
437 .rstout_enable_bit = BIT(8),
438 .wdt_enable_bit = BIT(8),
439 .wdt_counter_offset = 0x34,
440 .clock_init = armada370_wdt_clock_init,
441 .enabled = orion_enabled,
442 .start = armada370_start,
443 .stop = armada370_stop,
444};
445
446static const struct orion_watchdog_data armadaxp_data = {
447 .rstout_enable_bit = BIT(8),
448 .wdt_enable_bit = BIT(8),
449 .wdt_counter_offset = 0x34,
450 .clock_init = armadaxp_wdt_clock_init,
451 .enabled = orion_enabled,
452 .start = armada370_start,
453 .stop = armada370_stop,
454};
455
456static const struct orion_watchdog_data armada375_data = {
457 .rstout_enable_bit = BIT(8),
458 .rstout_mask_bit = BIT(10),
459 .wdt_enable_bit = BIT(8),
460 .wdt_counter_offset = 0x34,
461 .clock_init = armada375_wdt_clock_init,
462 .enabled = armada375_enabled,
463 .start = armada375_start,
464 .stop = armada375_stop,
465};
466
467static const struct orion_watchdog_data armada380_data = {
468 .rstout_enable_bit = BIT(8),
469 .rstout_mask_bit = BIT(10),
470 .wdt_enable_bit = BIT(8),
471 .wdt_counter_offset = 0x34,
472 .clock_init = armadaxp_wdt_clock_init,
473 .enabled = armada375_enabled,
474 .start = armada375_start,
475 .stop = armada375_stop,
476};
477
478static const struct of_device_id orion_wdt_of_match_table[] = {
479 {
480 .compatible = "marvell,orion-wdt",
481 .data = &orion_data,
482 },
483 {
484 .compatible = "marvell,armada-370-wdt",
485 .data = &armada370_data,
486 },
487 {
488 .compatible = "marvell,armada-xp-wdt",
489 .data = &armadaxp_data,
490 },
491 {
492 .compatible = "marvell,armada-375-wdt",
493 .data = &armada375_data,
494 },
495 {
496 .compatible = "marvell,armada-380-wdt",
497 .data = &armada380_data,
498 },
499 {},
500};
501MODULE_DEVICE_TABLE(of, orion_wdt_of_match_table);
502
503static int orion_wdt_get_regs(struct platform_device *pdev,
504 struct orion_watchdog *dev)
505{
506 struct device_node *node = pdev->dev.of_node;
507 struct resource *res;
508
509 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
510 if (!res)
511 return -ENODEV;
512 dev->reg = devm_ioremap(&pdev->dev, res->start,
513 resource_size(res));
514 if (!dev->reg)
515 return -ENOMEM;
516
517 /* Each supported compatible has some RSTOUT register quirk */
518 if (of_device_is_compatible(node, "marvell,orion-wdt")) {
519
520 dev->rstout = orion_wdt_ioremap_rstout(pdev, res->start &
521 INTERNAL_REGS_MASK);
522 if (!dev->rstout)
523 return -ENODEV;
524
525 } else if (of_device_is_compatible(node, "marvell,armada-370-wdt") ||
526 of_device_is_compatible(node, "marvell,armada-xp-wdt")) {
527
528 /* Dedicated RSTOUT register, can be requested. */
529 dev->rstout = devm_platform_ioremap_resource(pdev, 1);
530 if (IS_ERR(dev->rstout))
531 return PTR_ERR(dev->rstout);
532
533 } else if (of_device_is_compatible(node, "marvell,armada-375-wdt") ||
534 of_device_is_compatible(node, "marvell,armada-380-wdt")) {
535
536 /* Dedicated RSTOUT register, can be requested. */
537 dev->rstout = devm_platform_ioremap_resource(pdev, 1);
538 if (IS_ERR(dev->rstout))
539 return PTR_ERR(dev->rstout);
540
541 res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
542 if (!res)
543 return -ENODEV;
544 dev->rstout_mask = devm_ioremap(&pdev->dev, res->start,
545 resource_size(res));
546 if (!dev->rstout_mask)
547 return -ENOMEM;
548
549 } else {
550 return -ENODEV;
551 }
552
553 return 0;
554}
555
556static int orion_wdt_probe(struct platform_device *pdev)
557{
558 struct orion_watchdog *dev;
559 const struct of_device_id *match;
560 unsigned int wdt_max_duration; /* (seconds) */
561 int ret, irq;
562
563 dev = devm_kzalloc(&pdev->dev, sizeof(struct orion_watchdog),
564 GFP_KERNEL);
565 if (!dev)
566 return -ENOMEM;
567
568 match = of_match_device(orion_wdt_of_match_table, &pdev->dev);
569 if (!match)
570 /* Default legacy match */
571 match = &orion_wdt_of_match_table[0];
572
573 dev->wdt.info = &orion_wdt_info;
574 dev->wdt.ops = &orion_wdt_ops;
575 dev->wdt.min_timeout = 1;
576 dev->data = match->data;
577
578 ret = orion_wdt_get_regs(pdev, dev);
579 if (ret)
580 return ret;
581
582 ret = dev->data->clock_init(pdev, dev);
583 if (ret) {
584 dev_err(&pdev->dev, "cannot initialize clock\n");
585 return ret;
586 }
587
588 wdt_max_duration = WDT_MAX_CYCLE_COUNT / dev->clk_rate;
589
590 dev->wdt.timeout = wdt_max_duration;
591 dev->wdt.max_timeout = wdt_max_duration;
592 dev->wdt.parent = &pdev->dev;
593 watchdog_init_timeout(&dev->wdt, heartbeat, &pdev->dev);
594
595 platform_set_drvdata(pdev, &dev->wdt);
596 watchdog_set_drvdata(&dev->wdt, dev);
597
598 /*
599 * Let's make sure the watchdog is fully stopped, unless it's
600 * explicitly enabled. This may be the case if the module was
601 * removed and re-inserted, or if the bootloader explicitly
602 * set a running watchdog before booting the kernel.
603 */
604 if (!orion_wdt_enabled(&dev->wdt))
605 orion_wdt_stop(&dev->wdt);
606 else
607 set_bit(WDOG_HW_RUNNING, &dev->wdt.status);
608
609 /* Request the IRQ only after the watchdog is disabled */
610 irq = platform_get_irq_optional(pdev, 0);
611 if (irq > 0) {
612 /*
613 * Not all supported platforms specify an interrupt for the
614 * watchdog, so let's make it optional.
615 */
616 ret = devm_request_irq(&pdev->dev, irq, orion_wdt_irq, 0,
617 pdev->name, dev);
618 if (ret < 0) {
619 dev_err(&pdev->dev, "failed to request IRQ\n");
620 goto disable_clk;
621 }
622 }
623
624 /* Optional 2nd interrupt for pretimeout */
625 irq = platform_get_irq_optional(pdev, 1);
626 if (irq > 0) {
627 orion_wdt_info.options |= WDIOF_PRETIMEOUT;
628 ret = devm_request_irq(&pdev->dev, irq, orion_wdt_pre_irq,
629 0, pdev->name, dev);
630 if (ret < 0) {
631 dev_err(&pdev->dev, "failed to request IRQ\n");
632 goto disable_clk;
633 }
634 }
635
636
637 watchdog_set_nowayout(&dev->wdt, nowayout);
638 ret = watchdog_register_device(&dev->wdt);
639 if (ret)
640 goto disable_clk;
641
642 pr_info("Initial timeout %d sec%s\n",
643 dev->wdt.timeout, nowayout ? ", nowayout" : "");
644 return 0;
645
646disable_clk:
647 clk_disable_unprepare(dev->clk);
648 clk_put(dev->clk);
649 return ret;
650}
651
652static int orion_wdt_remove(struct platform_device *pdev)
653{
654 struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
655 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
656
657 watchdog_unregister_device(wdt_dev);
658 clk_disable_unprepare(dev->clk);
659 clk_put(dev->clk);
660 return 0;
661}
662
663static void orion_wdt_shutdown(struct platform_device *pdev)
664{
665 struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
666 orion_wdt_stop(wdt_dev);
667}
668
669static struct platform_driver orion_wdt_driver = {
670 .probe = orion_wdt_probe,
671 .remove = orion_wdt_remove,
672 .shutdown = orion_wdt_shutdown,
673 .driver = {
674 .name = "orion_wdt",
675 .of_match_table = orion_wdt_of_match_table,
676 },
677};
678
679module_platform_driver(orion_wdt_driver);
680
681MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
682MODULE_DESCRIPTION("Orion Processor Watchdog");
683
684module_param(heartbeat, int, 0);
685MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
686
687module_param(nowayout, bool, 0);
688MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
689 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
690
691MODULE_LICENSE("GPL v2");
692MODULE_ALIAS("platform:orion_wdt");