1 // SPDX-License-Identifier: GPL-2.0-or-later
3  *	i6300esb:	Watchdog timer driver for Intel 6300ESB chipset
8  *	based on i810-tco.c which is in turn based on softdog.c
12  *	6300ESB chip : document number 300641-004
21  *	Change driver to use the watchdog subsystem
35 #include <linux/watchdog.h>
49 #define ESB_TIMER1_REG(w) ((w)->base + 0x00)/* Timer1 value after each reset */
50 #define ESB_TIMER2_REG(w) ((w)->base + 0x04)/* Timer2 value after each reset */
51 #define ESB_GINTSR_REG(w) ((w)->base + 0x08)/* General Interrupt Status Reg  */
52 #define ESB_RELOAD_REG(w) ((w)->base + 0x0c)/* Reload register               */
55 #define ESB_WDT_FUNC    (0x01 << 2)   /* Watchdog functionality            */
56 #define ESB_WDT_ENABLE  (0x01 << 1)   /* Enable WDT                        */
60 #define ESB_WDT_REBOOT  (0x01 << 5)   /* Enable reboot on timeout          */
65 #define ESB_WDT_TIMEOUT (0x01 << 9)    /* Watchdog timed out                */
82 	"Watchdog heartbeat in seconds. (" ESB_HEARTBEAT_RANGE
88 		"Watchdog cannot be stopped once started (default="
119 	int _wdd_nowayout = test_bit(WDOG_NO_WAY_OUT, &wdd->status);  in esb_timer_start()
124 	/* Enable or Enable + Lock? */  in esb_timer_start()
126 	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, val);  in esb_timer_start()
139 	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x0);  in esb_timer_stop()
140 	pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val);  in esb_timer_stop()
142 	/* Returns 0 if the timer was disabled, non-zero otherwise */  in esb_timer_stop()
183 	wdd->timeout = time;  in esb_timer_set_heartbeat()
188  * Watchdog Subsystem Interfaces
219 	if (pci_enable_device(edev->pdev)) {  in esb_getdevice()
220 		dev_err(&edev->pdev->dev, "failed to enable device\n");  in esb_getdevice()
224 	if (pci_request_region(edev->pdev, 0, ESB_MODULE_NAME)) {  in esb_getdevice()
225 		dev_err(&edev->pdev->dev, "failed to request region\n");  in esb_getdevice()
229 	edev->base = pci_ioremap_bar(edev->pdev, 0);  in esb_getdevice()
230 	if (edev->base == NULL) {  in esb_getdevice()
232 		dev_err(&edev->pdev->dev, "failed to get BASEADDR\n");  in esb_getdevice()
237 	dev_set_drvdata(&edev->pdev->dev, edev);  in esb_getdevice()
241 	pci_release_region(edev->pdev, 0);  in esb_getdevice()
243 	pci_disable_device(edev->pdev);  in esb_getdevice()
255 	 * Bit    5 : 0 = Enable WDT_OUTPUT  in esb_initdevice()
259 	 * The watchdog has two timers, it can be setup so that the  in esb_initdevice()
265 	pci_write_config_word(edev->pdev, ESB_CONFIG_REG, 0x0003);  in esb_initdevice()
268 	pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val1);  in esb_initdevice()
270 		dev_warn(&edev->pdev->dev, "nowayout already set\n");  in esb_initdevice()
272 	/* Set the timer to watchdog mode and disable it for now */  in esb_initdevice()
273 	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x00);  in esb_initdevice()
275 	/* Check if the watchdog was previously triggered */  in esb_initdevice()
279 		edev->wdd.bootstatus = WDIOF_CARDRESET;  in esb_initdevice()
286 	esb_timer_set_heartbeat(&edev->wdd, edev->wdd.timeout);  in esb_initdevice()
295 	edev = devm_kzalloc(&pdev->dev, sizeof(*edev), GFP_KERNEL);  in esb_probe()
297 		return -ENOMEM;  in esb_probe()
299 	/* Check whether or not the hardware watchdog is there */  in esb_probe()
300 	edev->pdev = pdev;  in esb_probe()
302 		return -ENODEV;  in esb_probe()
304 	/* Initialize the watchdog and make sure it does not run */  in esb_probe()
305 	edev->wdd.info = &esb_info;  in esb_probe()
306 	edev->wdd.ops = &esb_ops;  in esb_probe()
307 	edev->wdd.min_timeout = ESB_HEARTBEAT_MIN;  in esb_probe()
308 	edev->wdd.max_timeout = ESB_HEARTBEAT_MAX;  in esb_probe()
309 	edev->wdd.timeout = ESB_HEARTBEAT_DEFAULT;  in esb_probe()
310 	watchdog_init_timeout(&edev->wdd, heartbeat, NULL);  in esb_probe()
311 	watchdog_set_nowayout(&edev->wdd, nowayout);  in esb_probe()
312 	watchdog_stop_on_reboot(&edev->wdd);  in esb_probe()
313 	watchdog_stop_on_unregister(&edev->wdd);  in esb_probe()
316 	/* Register the watchdog so that userspace has access to it */  in esb_probe()
317 	ret = watchdog_register_device(&edev->wdd);  in esb_probe()
320 	dev_info(&pdev->dev,  in esb_probe()
322 		edev->wdd.timeout, nowayout);  in esb_probe()
326 	iounmap(edev->base);  in esb_probe()
327 	pci_release_region(edev->pdev, 0);  in esb_probe()
328 	pci_disable_device(edev->pdev);  in esb_probe()
334 	struct esb_dev *edev = dev_get_drvdata(&pdev->dev);  in esb_remove()
336 	watchdog_unregister_device(&edev->wdd);  in esb_remove()
337 	iounmap(edev->base);  in esb_remove()
338 	pci_release_region(edev->pdev, 0);  in esb_remove()
339 	pci_disable_device(edev->pdev);  in esb_remove()
352 MODULE_DESCRIPTION("Watchdog driver for Intel 6300ESB chipsets");