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[cor.git] / drivers / watchdog / orion_wdt.c
blob1cccf8eb1c5d4ed4cdad590027cc181b89dfb146
1 /*
2 * drivers/watchdog/orion_wdt.c
4 * Watchdog driver for Orion/Kirkwood processors
6 * Author: Sylver Bruneau <sylver.bruneau@googlemail.com>
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.
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
28 /* RSTOUT mask register physical address for Orion5x, Kirkwood and Dove */
29 #define ORION_RSTOUT_MASK_OFFSET 0x20108
31 /* Internal registers can be configured at any 1 MiB aligned address */
32 #define INTERNAL_REGS_MASK ~(SZ_1M - 1)
35 * Watchdog timer block registers.
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)
42 #define TIMER_A370_STATUS 0x0004
43 #define WDT_A370_EXPIRED BIT(31)
44 #define TIMER1_STATUS_BIT BIT(8)
46 #define TIMER1_VAL_OFF 0x001c
48 #define WDT_MAX_CYCLE_COUNT 0xffffffff
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)
54 static bool nowayout = WATCHDOG_NOWAYOUT;
55 static int heartbeat = -1; /* module parameter (seconds) */
57 struct orion_watchdog;
59 struct 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 *);
71 struct 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;
81 static int orion_wdt_clock_init(struct platform_device *pdev,
82 struct orion_watchdog *dev)
84 int ret;
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;
95 dev->clk_rate = clk_get_rate(dev->clk);
96 return 0;
99 static int armada370_wdt_clock_init(struct platform_device *pdev,
100 struct orion_watchdog *dev)
102 int ret;
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;
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));
118 dev->clk_rate = clk_get_rate(dev->clk) / WDT_A370_RATIO;
119 return 0;
122 static int armada375_wdt_clock_init(struct platform_device *pdev,
123 struct orion_watchdog *dev)
125 int ret;
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;
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);
140 return 0;
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);
148 ret = clk_prepare_enable(dev->clk);
149 if (ret) {
150 clk_put(dev->clk);
151 return ret;
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;
159 return 0;
162 static int armadaxp_wdt_clock_init(struct platform_device *pdev,
163 struct orion_watchdog *dev)
165 int ret;
166 u32 val;
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;
177 /* Fix the wdt and timer1 clock freqency to 25MHz */
178 val = WDT_AXP_FIXED_ENABLE_BIT | TIMER1_FIXED_ENABLE_BIT;
179 atomic_io_modify(dev->reg + TIMER_CTRL, val, val);
181 dev->clk_rate = clk_get_rate(dev->clk);
182 return 0;
185 static int orion_wdt_ping(struct watchdog_device *wdt_dev)
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);
195 return 0;
198 static int armada375_start(struct watchdog_device *wdt_dev)
200 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
201 u32 reg;
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);
210 /* Clear the watchdog expiration bit */
211 atomic_io_modify(dev->reg + TIMER_A370_STATUS, WDT_A370_EXPIRED, 0);
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);
219 /* Enable reset on watchdog */
220 reg = readl(dev->rstout);
221 reg |= dev->data->rstout_enable_bit;
222 writel(reg, dev->rstout);
224 atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit, 0);
225 return 0;
228 static int armada370_start(struct watchdog_device *wdt_dev)
230 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
231 u32 reg;
233 /* Set watchdog duration */
234 writel(dev->clk_rate * wdt_dev->timeout,
235 dev->reg + dev->data->wdt_counter_offset);
237 /* Clear the watchdog expiration bit */
238 atomic_io_modify(dev->reg + TIMER_A370_STATUS, WDT_A370_EXPIRED, 0);
240 /* Enable watchdog timer */
241 atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
242 dev->data->wdt_enable_bit);
244 /* Enable reset on watchdog */
245 reg = readl(dev->rstout);
246 reg |= dev->data->rstout_enable_bit;
247 writel(reg, dev->rstout);
248 return 0;
251 static int orion_start(struct watchdog_device *wdt_dev)
253 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
255 /* Set watchdog duration */
256 writel(dev->clk_rate * wdt_dev->timeout,
257 dev->reg + dev->data->wdt_counter_offset);
259 /* Enable watchdog timer */
260 atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
261 dev->data->wdt_enable_bit);
263 /* Enable reset on watchdog */
264 atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit,
265 dev->data->rstout_enable_bit);
267 return 0;
270 static int orion_wdt_start(struct watchdog_device *wdt_dev)
272 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
274 /* There are some per-SoC quirks to handle */
275 return dev->data->start(wdt_dev);
278 static int orion_stop(struct watchdog_device *wdt_dev)
280 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
282 /* Disable reset on watchdog */
283 atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit, 0);
285 /* Disable watchdog timer */
286 atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
288 return 0;
291 static int armada375_stop(struct watchdog_device *wdt_dev)
293 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
294 u32 reg, mask;
296 /* Disable reset on watchdog */
297 atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit,
298 dev->data->rstout_mask_bit);
299 reg = readl(dev->rstout);
300 reg &= ~dev->data->rstout_enable_bit;
301 writel(reg, dev->rstout);
303 /* Disable watchdog timer */
304 mask = dev->data->wdt_enable_bit;
305 if (wdt_dev->info->options & WDIOF_PRETIMEOUT)
306 mask |= TIMER1_ENABLE_BIT;
307 atomic_io_modify(dev->reg + TIMER_CTRL, mask, 0);
309 return 0;
312 static int armada370_stop(struct watchdog_device *wdt_dev)
314 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
315 u32 reg;
317 /* Disable reset on watchdog */
318 reg = readl(dev->rstout);
319 reg &= ~dev->data->rstout_enable_bit;
320 writel(reg, dev->rstout);
322 /* Disable watchdog timer */
323 atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
325 return 0;
328 static int orion_wdt_stop(struct watchdog_device *wdt_dev)
330 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
332 return dev->data->stop(wdt_dev);
335 static int orion_enabled(struct orion_watchdog *dev)
337 bool enabled, running;
339 enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
340 running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
342 return enabled && running;
345 static int armada375_enabled(struct orion_watchdog *dev)
347 bool masked, enabled, running;
349 masked = readl(dev->rstout_mask) & dev->data->rstout_mask_bit;
350 enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
351 running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
353 return !masked && enabled && running;
356 static int orion_wdt_enabled(struct watchdog_device *wdt_dev)
358 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
360 return dev->data->enabled(dev);
363 static unsigned int orion_wdt_get_timeleft(struct watchdog_device *wdt_dev)
365 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
366 return readl(dev->reg + dev->data->wdt_counter_offset) / dev->clk_rate;
369 static struct watchdog_info orion_wdt_info = {
370 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
371 .identity = "Orion Watchdog",
374 static const struct watchdog_ops orion_wdt_ops = {
375 .owner = THIS_MODULE,
376 .start = orion_wdt_start,
377 .stop = orion_wdt_stop,
378 .ping = orion_wdt_ping,
379 .get_timeleft = orion_wdt_get_timeleft,
382 static irqreturn_t orion_wdt_irq(int irq, void *devid)
384 panic("Watchdog Timeout");
385 return IRQ_HANDLED;
388 static irqreturn_t orion_wdt_pre_irq(int irq, void *devid)
390 struct orion_watchdog *dev = devid;
392 atomic_io_modify(dev->reg + TIMER_A370_STATUS,
393 TIMER1_STATUS_BIT, 0);
394 watchdog_notify_pretimeout(&dev->wdt);
395 return IRQ_HANDLED;
399 * The original devicetree binding for this driver specified only
400 * one memory resource, so in order to keep DT backwards compatibility
401 * we try to fallback to a hardcoded register address, if the resource
402 * is missing from the devicetree.
404 static void __iomem *orion_wdt_ioremap_rstout(struct platform_device *pdev,
405 phys_addr_t internal_regs)
407 struct resource *res;
408 phys_addr_t rstout;
410 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
411 if (res)
412 return devm_ioremap(&pdev->dev, res->start,
413 resource_size(res));
415 rstout = internal_regs + ORION_RSTOUT_MASK_OFFSET;
417 WARN(1, FW_BUG "falling back to hardcoded RSTOUT reg %pa\n", &rstout);
418 return devm_ioremap(&pdev->dev, rstout, 0x4);
421 static const struct orion_watchdog_data orion_data = {
422 .rstout_enable_bit = BIT(1),
423 .wdt_enable_bit = BIT(4),
424 .wdt_counter_offset = 0x24,
425 .clock_init = orion_wdt_clock_init,
426 .enabled = orion_enabled,
427 .start = orion_start,
428 .stop = orion_stop,
431 static const struct orion_watchdog_data armada370_data = {
432 .rstout_enable_bit = BIT(8),
433 .wdt_enable_bit = BIT(8),
434 .wdt_counter_offset = 0x34,
435 .clock_init = armada370_wdt_clock_init,
436 .enabled = orion_enabled,
437 .start = armada370_start,
438 .stop = armada370_stop,
441 static const struct orion_watchdog_data armadaxp_data = {
442 .rstout_enable_bit = BIT(8),
443 .wdt_enable_bit = BIT(8),
444 .wdt_counter_offset = 0x34,
445 .clock_init = armadaxp_wdt_clock_init,
446 .enabled = orion_enabled,
447 .start = armada370_start,
448 .stop = armada370_stop,
451 static const struct orion_watchdog_data armada375_data = {
452 .rstout_enable_bit = BIT(8),
453 .rstout_mask_bit = BIT(10),
454 .wdt_enable_bit = BIT(8),
455 .wdt_counter_offset = 0x34,
456 .clock_init = armada375_wdt_clock_init,
457 .enabled = armada375_enabled,
458 .start = armada375_start,
459 .stop = armada375_stop,
462 static const struct orion_watchdog_data armada380_data = {
463 .rstout_enable_bit = BIT(8),
464 .rstout_mask_bit = BIT(10),
465 .wdt_enable_bit = BIT(8),
466 .wdt_counter_offset = 0x34,
467 .clock_init = armadaxp_wdt_clock_init,
468 .enabled = armada375_enabled,
469 .start = armada375_start,
470 .stop = armada375_stop,
473 static const struct of_device_id orion_wdt_of_match_table[] = {
475 .compatible = "marvell,orion-wdt",
476 .data = &orion_data,
479 .compatible = "marvell,armada-370-wdt",
480 .data = &armada370_data,
483 .compatible = "marvell,armada-xp-wdt",
484 .data = &armadaxp_data,
487 .compatible = "marvell,armada-375-wdt",
488 .data = &armada375_data,
491 .compatible = "marvell,armada-380-wdt",
492 .data = &armada380_data,
496 MODULE_DEVICE_TABLE(of, orion_wdt_of_match_table);
498 static int orion_wdt_get_regs(struct platform_device *pdev,
499 struct orion_watchdog *dev)
501 struct device_node *node = pdev->dev.of_node;
502 struct resource *res;
504 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
505 if (!res)
506 return -ENODEV;
507 dev->reg = devm_ioremap(&pdev->dev, res->start,
508 resource_size(res));
509 if (!dev->reg)
510 return -ENOMEM;
512 /* Each supported compatible has some RSTOUT register quirk */
513 if (of_device_is_compatible(node, "marvell,orion-wdt")) {
515 dev->rstout = orion_wdt_ioremap_rstout(pdev, res->start &
516 INTERNAL_REGS_MASK);
517 if (!dev->rstout)
518 return -ENODEV;
520 } else if (of_device_is_compatible(node, "marvell,armada-370-wdt") ||
521 of_device_is_compatible(node, "marvell,armada-xp-wdt")) {
523 /* Dedicated RSTOUT register, can be requested. */
524 dev->rstout = devm_platform_ioremap_resource(pdev, 1);
525 if (IS_ERR(dev->rstout))
526 return PTR_ERR(dev->rstout);
528 } else if (of_device_is_compatible(node, "marvell,armada-375-wdt") ||
529 of_device_is_compatible(node, "marvell,armada-380-wdt")) {
531 /* Dedicated RSTOUT register, can be requested. */
532 dev->rstout = devm_platform_ioremap_resource(pdev, 1);
533 if (IS_ERR(dev->rstout))
534 return PTR_ERR(dev->rstout);
536 res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
537 if (!res)
538 return -ENODEV;
539 dev->rstout_mask = devm_ioremap(&pdev->dev, res->start,
540 resource_size(res));
541 if (!dev->rstout_mask)
542 return -ENOMEM;
544 } else {
545 return -ENODEV;
548 return 0;
551 static int orion_wdt_probe(struct platform_device *pdev)
553 struct orion_watchdog *dev;
554 const struct of_device_id *match;
555 unsigned int wdt_max_duration; /* (seconds) */
556 int ret, irq;
558 dev = devm_kzalloc(&pdev->dev, sizeof(struct orion_watchdog),
559 GFP_KERNEL);
560 if (!dev)
561 return -ENOMEM;
563 match = of_match_device(orion_wdt_of_match_table, &pdev->dev);
564 if (!match)
565 /* Default legacy match */
566 match = &orion_wdt_of_match_table[0];
568 dev->wdt.info = &orion_wdt_info;
569 dev->wdt.ops = &orion_wdt_ops;
570 dev->wdt.min_timeout = 1;
571 dev->data = match->data;
573 ret = orion_wdt_get_regs(pdev, dev);
574 if (ret)
575 return ret;
577 ret = dev->data->clock_init(pdev, dev);
578 if (ret) {
579 dev_err(&pdev->dev, "cannot initialize clock\n");
580 return ret;
583 wdt_max_duration = WDT_MAX_CYCLE_COUNT / dev->clk_rate;
585 dev->wdt.timeout = wdt_max_duration;
586 dev->wdt.max_timeout = wdt_max_duration;
587 dev->wdt.parent = &pdev->dev;
588 watchdog_init_timeout(&dev->wdt, heartbeat, &pdev->dev);
590 platform_set_drvdata(pdev, &dev->wdt);
591 watchdog_set_drvdata(&dev->wdt, dev);
594 * Let's make sure the watchdog is fully stopped, unless it's
595 * explicitly enabled. This may be the case if the module was
596 * removed and re-inserted, or if the bootloader explicitly
597 * set a running watchdog before booting the kernel.
599 if (!orion_wdt_enabled(&dev->wdt))
600 orion_wdt_stop(&dev->wdt);
601 else
602 set_bit(WDOG_HW_RUNNING, &dev->wdt.status);
604 /* Request the IRQ only after the watchdog is disabled */
605 irq = platform_get_irq(pdev, 0);
606 if (irq > 0) {
608 * Not all supported platforms specify an interrupt for the
609 * watchdog, so let's make it optional.
611 ret = devm_request_irq(&pdev->dev, irq, orion_wdt_irq, 0,
612 pdev->name, dev);
613 if (ret < 0) {
614 dev_err(&pdev->dev, "failed to request IRQ\n");
615 goto disable_clk;
619 /* Optional 2nd interrupt for pretimeout */
620 irq = platform_get_irq(pdev, 1);
621 if (irq > 0) {
622 orion_wdt_info.options |= WDIOF_PRETIMEOUT;
623 ret = devm_request_irq(&pdev->dev, irq, orion_wdt_pre_irq,
624 0, pdev->name, dev);
625 if (ret < 0) {
626 dev_err(&pdev->dev, "failed to request IRQ\n");
627 goto disable_clk;
632 watchdog_set_nowayout(&dev->wdt, nowayout);
633 ret = watchdog_register_device(&dev->wdt);
634 if (ret)
635 goto disable_clk;
637 pr_info("Initial timeout %d sec%s\n",
638 dev->wdt.timeout, nowayout ? ", nowayout" : "");
639 return 0;
641 disable_clk:
642 clk_disable_unprepare(dev->clk);
643 clk_put(dev->clk);
644 return ret;
647 static int orion_wdt_remove(struct platform_device *pdev)
649 struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
650 struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
652 watchdog_unregister_device(wdt_dev);
653 clk_disable_unprepare(dev->clk);
654 clk_put(dev->clk);
655 return 0;
658 static void orion_wdt_shutdown(struct platform_device *pdev)
660 struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
661 orion_wdt_stop(wdt_dev);
664 static struct platform_driver orion_wdt_driver = {
665 .probe = orion_wdt_probe,
666 .remove = orion_wdt_remove,
667 .shutdown = orion_wdt_shutdown,
668 .driver = {
669 .name = "orion_wdt",
670 .of_match_table = orion_wdt_of_match_table,
674 module_platform_driver(orion_wdt_driver);
676 MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
677 MODULE_DESCRIPTION("Orion Processor Watchdog");
679 module_param(heartbeat, int, 0);
680 MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
682 module_param(nowayout, bool, 0);
683 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
684 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
686 MODULE_LICENSE("GPL v2");
687 MODULE_ALIAS("platform:orion_wdt");