Differential D39824 Diff 121059 sys/arm64/apple/apple_wdog.c

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sys/arm64/apple/apple_wdog.c

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				/*-
				* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
				*
				* Copyright (c) 2022 Michael J. Karels <karels@freebsd.org>
				* Copyright (c) 2012 Alexander Rybalko <ray@freebsd.org>
				* All rights reserved.
				emasteUnsubmitted Not Done Inline Actions Is this copy-paste from elsewhere? (Can we remove "All rights reserved."?) emaste: Is this copy-paste from elsewhere? (Can we remove "All rights reserved."?)
				karelsUnsubmitted Not Done Inline Actions It's from bcm2835_wdog.c, which has All Rights Reserved. Should we mention the source in a comment? karels: It's from bcm2835_wdog.c, which has All Rights Reserved. Should we mention the source in a…
				kevansAuthorUnsubmitted Done Inline Actions CC @ray kevans: CC @ray
				emasteUnsubmitted Not Done Inline Actions IMO it's worth having something like "based on bcm2835_wdog.c". We can drop the "All rights reserved" (from this copy) if @karels and @ray agree emaste: IMO it's worth having something like "based on bcm2835_wdog.c". We can drop the "All rights…
				karelsUnsubmitted Not Done Inline Actions Fine with me; I wouldn't have included it except that it was in the earlier file. karels: Fine with me; I wouldn't have included it except that it was in the earlier file.
				rayUnsubmitted Not Done Inline Actions Fine for me too. ray: Fine for me too.
				*
				* Redistribution and use in source and binary forms, with or without
				* modification, are permitted provided that the following conditions
				* are met:
				* 1. Redistributions of source code must retain the above copyright
				* notice, this list of conditions and the following disclaimer.
				* 2. Redistributions in binary form must reproduce the above copyright
				* notice, this list of conditions and the following disclaimer in the
				* documentation and/or other materials provided with the distribution.
				*
				* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
				* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
				* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
				* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
				* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
				* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
				* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
				* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
				* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
				* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
				* SUCH DAMAGE.
				*/
				#include <sys/cdefs.h>
				__FBSDID("$FreeBSD$");

				#include <sys/param.h>
				#include <sys/bus.h>
				#include <sys/eventhandler.h>
				#include <sys/kernel.h>
				#include <sys/limits.h>
				#include <sys/lock.h>
				#include <sys/module.h>
				#include <sys/mutex.h>
				#include <sys/reboot.h>
				#include <sys/rman.h>
				#include <sys/systm.h>
				#include <sys/watchdog.h>

				#include <dev/ofw/openfirm.h>
				#include <dev/ofw/ofw_bus.h>
				#include <dev/ofw/ofw_bus_subr.h>

				#include <dev/extres/clk/clk.h>

				#include <machine/bus.h>
				#include <machine/machdep.h>

				#define APPLE_WDOG_WD0_TIMER 0x0000
				#define APPLE_WDOG_WD0_RESET 0x0004
				#define APPLE_WDOG_WD0_INTR 0x0008
				#define APPLE_WDOG_WD0_CNTL 0x000c

				#define APPLE_WDOG_WD1_TIMER 0x0010
				#define APPLE_WDOG_WD1_RESET 0x0014
				#define APPLE_WDOG_WD1_CNTL 0x001c

				#define APPLE_WDOG_WD2_TIMER 0x0020
				#define APPLE_WDOG_WD2_RESET 0x0024
				#define APPLE_WDOG_WD2_CNTL 0x002c

				#define APPLE_WDOG_CNTL_INTENABLE 0x0001
				#define APPLE_WDOG_CNTL_INTSTAT 0x0002
				#define APPLE_WDOG_CNTL_RSTENABLE 0x0004

				#define READ(_sc, _r) bus_space_read_4((_sc)->bst, (_sc)->bsh, (_r))
				#define WRITE(_sc, _r, _v) bus_space_write_4((_sc)->bst, (_sc)->bsh, (_r), (_v))

				struct apple_wdog_softc {
				device_t dev;
				struct resource * res;
				bus_space_tag_t bst;
				bus_space_handle_t bsh;
				clk_t clk;
				uint64_t clk_freq;
				struct mtx mtx;
				};

				static struct ofw_compat_data compat_data[] = {
				{"apple,wdt", 1},
				{NULL, 0}
				};

				static void apple_wdog_watchdog_fn(void private, u_int cmd, int error);
				static void apple_wdog_reboot_system(void *, int);

				static int
				apple_wdog_probe(device_t dev)
				{

				if (!ofw_bus_status_okay(dev))
				return (ENXIO);

				if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
				return (ENXIO);

				device_set_desc(dev, "Apple Watchdog");

				return (BUS_PROBE_DEFAULT);
				}

				static int
				apple_wdog_attach(device_t dev)
				{
				struct apple_wdog_softc *sc;
				int error, rid;

				sc = device_get_softc(dev);
				sc->dev = dev;

				rid = 0;
				sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
				if (sc->res == NULL) {
				device_printf(dev, "could not allocate memory resource\n");
				return (ENXIO);
				}

				sc->bst = rman_get_bustag(sc->res);
				sc->bsh = rman_get_bushandle(sc->res);

				error = clk_get_by_ofw_index(dev, 0, 0, &sc->clk);
				if (error != 0) {
				device_printf(dev, "cannot get clock\n");
				goto fail;
				}
				error = clk_enable(sc->clk);
				if (error != 0) {
				device_printf(dev, "cannot enable clock\n");
				goto fail;
				}
				error = clk_get_freq(sc->clk, &sc->clk_freq);
				if (error != 0) {
				device_printf(dev, "cannot get base frequency\n");
				goto fail_clk;
				}

				mtx_init(&sc->mtx, "Apple Watchdog", "apple_wdog", MTX_DEF);
				EVENTHANDLER_REGISTER(watchdog_list, apple_wdog_watchdog_fn, sc, 0);
				EVENTHANDLER_REGISTER(shutdown_final, apple_wdog_reboot_system, sc,
				SHUTDOWN_PRI_LAST);

				/* Reset the watchdog timers. */
				WRITE(sc, APPLE_WDOG_WD0_CNTL, 0);
				WRITE(sc, APPLE_WDOG_WD1_CNTL, 0);

				return (0);

				fail_clk:
				clk_disable(sc->clk);
				fail:
				bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->res);
				return (error);
				}

				static void
				apple_wdog_watchdog_fn(void private, u_int cmd, int error)
				{
				struct apple_wdog_softc *sc;
				uint64_t sec;
				uint32_t ticks, sec_max;

				sc = private;
				mtx_lock(&sc->mtx);

				cmd &= WD_INTERVAL;

				if (cmd > 0) {
				sec = ((uint64_t)1 << (cmd & WD_INTERVAL)) / 1000000000;
				sec_max = UINT_MAX / sc->clk_freq;
				if (sec == 0 \|\| sec > sec_max) {
				/*
				* Can't arm
				* disable watchdog as watchdog(9) requires
				*/
				device_printf(sc->dev,
				"Can't arm, timeout must be between 1-%d seconds\n",
				sec_max);
				WRITE(sc, APPLE_WDOG_WD1_CNTL, 0);
				mtx_unlock(&sc->mtx);
				*error = EINVAL;
				return;
				}

				ticks = sec * sc->clk_freq;
				WRITE(sc, APPLE_WDOG_WD1_TIMER, 0);
				WRITE(sc, APPLE_WDOG_WD1_RESET, ticks);
				WRITE(sc, APPLE_WDOG_WD1_CNTL, APPLE_WDOG_CNTL_RSTENABLE);

				*error = 0;
				} else
				WRITE(sc, APPLE_WDOG_WD1_CNTL, 0);

				mtx_unlock(&sc->mtx);
				}

				static void
				apple_wdog_reboot_system(void *private, int howto)
				{
				struct apple_wdog_softc *sc = private;

				/* Only handle reset. */
				if ((howto & (RB_HALT \| RB_POWEROFF)) != 0)
				return;

				printf("Resetting system ... ");

				WRITE(sc, APPLE_WDOG_WD1_CNTL, APPLE_WDOG_CNTL_RSTENABLE);
				WRITE(sc, APPLE_WDOG_WD1_RESET, 1);
				WRITE(sc, APPLE_WDOG_WD1_TIMER, 0);

				/* Wait for watchdog timeout; should take milliseconds. */
				DELAY(2000000);

				/* Not reached ... one hopes. */
				printf("failed to reset.\n");
				}

				static device_method_t apple_wdog_methods[] = {
				DEVMETHOD(device_probe, apple_wdog_probe),
				DEVMETHOD(device_attach, apple_wdog_attach),

				DEVMETHOD_END
				};

				static driver_t apple_wdog_driver = {
				"apple_wdog",
				apple_wdog_methods,
				sizeof(struct apple_wdog_softc),
				};

				DRIVER_MODULE(apple_wdog, simplebus, apple_wdog_driver, 0, 0);