1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
30  * This is a driver for watchdog timer present in AMD SB600/SB7xx/SB8xx
34  * - AMD SB600 Register Reference Guide, Public Version,  Rev. 3.03 (SB600 RRG)
35 …*   http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/46155_sb600_rrg_pub_3.…
36  * - AMD SB700/710/750 Register Reference Guide (RRG)
38  * - AMD SB700/710/750 Register Programming Requirements (RPR)
40  * - AMD SB800-Series Southbridges Register Reference Guide (RRG)
42  * Please see the following for Watchdog Resource Table specification:
43  * - Watchdog Timer Hardware Requirements for Windows Server 2003 (WDRT)
44  *   http://www.microsoft.com/whdc/system/sysinternals/watchdog.mspx
45  * AMD SB600/SB7xx/SB8xx watchdog hardware seems to conform to the above
64 #include <sys/watchdog.h>
71  * Registers in the Watchdog IO space.
149 	return (bus_read_4(sc->res_ctrl, 0));  in wdctrl_read()
155 	bus_write_4(sc->res_ctrl, 0, val);  in wdctrl_write()
161 	return (bus_read_4(sc->res_count, 0));  in wdcount_read()
167 	bus_write_4(sc->res_count, 0, val);  in wdcount_write()
178 	sc->active = 1;  in amdsbwd_tmr_enable()
179 	amdsbwd_verbose_printf(sc->dev, "timer enabled\n");  in amdsbwd_tmr_enable()
190 	sc->active = 0;  in amdsbwd_tmr_disable()
191 	amdsbwd_verbose_printf(sc->dev, "timer disabled\n");  in amdsbwd_tmr_disable()
210 	sc->timeout = timeout;  in amdsbwd_tmr_set()
211 	amdsbwd_verbose_printf(sc->dev, "timeout set to %u ticks\n", timeout);  in amdsbwd_tmr_set()
224 			timeout = (uint64_t)1 << (cmd - WD_TO_1MS);  in amdsbwd_event()
225 			timeout = timeout / sc->ms_per_tick;  in amdsbwd_event()
230 		/* For a too long timeout stop the timer. */  in amdsbwd_event()
231 		if (timeout > sc->max_ticks)  in amdsbwd_event()
238 		if (timeout != sc->timeout)  in amdsbwd_event()
240 		if (!sc->active)  in amdsbwd_event()
245 		if (sc->active)  in amdsbwd_event()
294 		device_printf(dev, "Previous Reset was caused by Watchdog\n");  in amdsbwd_probe_sb7xx()
299 		*addr |= pmio_read(pmres, AMDSB_PM_WDT_BASE_MSB - i);  in amdsbwd_probe_sb7xx()
303 	/* Set watchdog timer tick to 1s. */  in amdsbwd_probe_sb7xx()
309 	/* Enable watchdog device (in stopped state). */  in amdsbwd_probe_sb7xx()
315 	 * XXX TODO: Ensure that watchdog decode is enabled  in amdsbwd_probe_sb7xx()
318 	device_set_desc(dev, "AMD SB600/SB7xx Watchdog Timer");  in amdsbwd_probe_sb7xx()
335 	for (i = 3; i >= 0; i--) {  in amdsbwd_probe_sb8xx()
342 		device_printf(dev, "Previous Reset was caused by Watchdog\n");  in amdsbwd_probe_sb8xx()
347 		*addr |= pmio_read(pmres, AMDSB8_PM_WDT_EN + 3 - i);  in amdsbwd_probe_sb8xx()
351 	/* Set watchdog timer tick to 1s. */  in amdsbwd_probe_sb8xx()
362 	 * Enable watchdog device (in stopped state)  in amdsbwd_probe_sb8xx()
373 	device_set_desc(dev, "AMD SB8xx/SB9xx/Axx Watchdog Timer");  in amdsbwd_probe_sb8xx()
382 	 * Enable decoding of watchdog MMIO address.  in amdsbwd_probe_fch41()
394 		/* Fixed offset for the watchdog within ACPI MMIO range. */  in amdsbwd_probe_fch41()
398 		/* Special fixed MMIO range for the watchdog. */  in amdsbwd_probe_fch41()
403 	 * Set watchdog timer tick to 1s and  in amdsbwd_probe_fch41()
404 	 * enable the watchdog device (in stopped state).  in amdsbwd_probe_fch41()
417 	device_set_descf(dev, "%s FCH Rev 41h+ Watchdog Timer",  in amdsbwd_probe_fch41()
487 	sc->max_ticks = UINT16_MAX;  in amdsbwd_attach_sb()
488 	sc->rid_ctrl = 0;  in amdsbwd_attach_sb()
489 	sc->rid_count = 1;  in amdsbwd_attach_sb()
491 	sc->ms_per_tick = 1000;  in amdsbwd_attach_sb()
493 	sc->res_ctrl = bus_alloc_resource_any(dev, SYS_RES_MEMORY,  in amdsbwd_attach_sb()
494 	    &sc->rid_ctrl, RF_ACTIVE);  in amdsbwd_attach_sb()
495 	if (sc->res_ctrl == NULL) {  in amdsbwd_attach_sb()
499 	sc->res_count = bus_alloc_resource_any(dev, SYS_RES_MEMORY,  in amdsbwd_attach_sb()
500 	    &sc->rid_count, RF_ACTIVE);  in amdsbwd_attach_sb()
501 	if (sc->res_count == NULL) {  in amdsbwd_attach_sb()
515 	sc->dev = dev;  in amdsbwd_attach()
526 	/* Setup initial state of Watchdog Control. */  in amdsbwd_attach()
530 		device_printf(dev, "watchdog hardware is disabled\n");  in amdsbwd_attach()
534 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, amdsbwd_event, sc,  in amdsbwd_attach()
550 	if (sc->ev_tag != NULL)  in amdsbwd_detach()
551 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);  in amdsbwd_detach()
553 	if (sc->active)  in amdsbwd_detach()
556 	if (sc->res_ctrl != NULL)  in amdsbwd_detach()
557 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_ctrl,  in amdsbwd_detach()
558 		    sc->res_ctrl);  in amdsbwd_detach()
560 	if (sc->res_count != NULL)  in amdsbwd_detach()
561 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_count,  in amdsbwd_detach()
562 		    sc->res_count);  in amdsbwd_detach()
587 	if (sc->active) {  in amdsbwd_resume()
588 		amdsbwd_tmr_set(sc, sc->timeout);  in amdsbwd_resume()