xref: /netbsd-src/sys/arch/arm/nvidia/tegra_timer.c (revision 200d779b75dbeafa7bc01fd0f60bc61185f6967b)
1 /* $NetBSD: tegra_timer.c,v 1.1 2015/05/30 13:25:55 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2015 Jared D. McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: tegra_timer.c,v 1.1 2015/05/30 13:25:55 jmcneill Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/intr.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/wdog.h>
39 
40 #include <dev/sysmon/sysmonvar.h>
41 
42 #include <arm/nvidia/tegra_reg.h>
43 #include <arm/nvidia/tegra_timerreg.h>
44 #include <arm/nvidia/tegra_var.h>
45 
46 #define TEGRA_TIMER_WDOG_PERIOD_DEFAULT	10
47 
48 static int	tegra_timer_match(device_t, cfdata_t, void *);
49 static void	tegra_timer_attach(device_t, device_t, void *);
50 
51 struct tegra_timer_softc {
52 	device_t		sc_dev;
53 	bus_space_tag_t		sc_bst;
54 	bus_space_handle_t	sc_bsh;
55 
56 	struct sysmon_wdog	sc_smw;
57 };
58 
59 static int	tegra_timer_wdt_setmode(struct sysmon_wdog *);
60 static int	tegra_timer_wdt_tickle(struct sysmon_wdog *);
61 
62 CFATTACH_DECL_NEW(tegra_timer, sizeof(struct tegra_timer_softc),
63 	tegra_timer_match, tegra_timer_attach, NULL, NULL);
64 
65 #define TIMER_READ(sc, reg)			\
66     bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
67 #define TIMER_WRITE(sc, reg, val)		\
68     bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
69 #define TIMER_SET_CLEAR(sc, reg, set, clr)	\
70     tegra_reg_set_clear((sc)->sc_bst, (sc)->sc_bsh, (reg), (set), (clr))
71 
72 static int
73 tegra_timer_match(device_t parent, cfdata_t cf, void *aux)
74 {
75 	return 1;
76 }
77 
78 static void
79 tegra_timer_attach(device_t parent, device_t self, void *aux)
80 {
81 	struct tegra_timer_softc * const sc = device_private(self);
82 	struct tegraio_attach_args * const tio = aux;
83 	const struct tegra_locators * const loc = &tio->tio_loc;
84 
85 	sc->sc_dev = self;
86 	sc->sc_bst = tio->tio_bst;
87 	bus_space_subregion(tio->tio_bst, tio->tio_bsh,
88 	    loc->loc_offset, loc->loc_size, &sc->sc_bsh);
89 
90 	aprint_naive("\n");
91 	aprint_normal(": Timers\n");
92 
93 	sc->sc_smw.smw_name = device_xname(self);
94 	sc->sc_smw.smw_cookie = sc;
95 	sc->sc_smw.smw_setmode = tegra_timer_wdt_setmode;
96 	sc->sc_smw.smw_tickle = tegra_timer_wdt_tickle;
97 	sc->sc_smw.smw_period = TEGRA_TIMER_WDOG_PERIOD_DEFAULT;
98 
99 	aprint_normal_dev(self, "default watchdog period is %u seconds\n",
100 	    sc->sc_smw.smw_period);
101 
102 	if (sysmon_wdog_register(&sc->sc_smw) != 0)
103 		aprint_error_dev(self, "couldn't register with sysmon\n");
104 }
105 
106 static int
107 tegra_timer_wdt_setmode(struct sysmon_wdog *smw)
108 {
109 	struct tegra_timer_softc * const sc = smw->smw_cookie;
110 
111 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
112 		TIMER_SET_CLEAR(sc, TMR1_PTV_REG, 0, TMR_PTV_EN);
113 		tegra_car_wdt_enable(1, false);
114 	} else {
115 		if (smw->smw_period == WDOG_PERIOD_DEFAULT) {
116 			sc->sc_smw.smw_period = TEGRA_TIMER_WDOG_PERIOD_DEFAULT;
117 		} else if (smw->smw_period == 0 || smw->smw_period > 1000) {
118 			return EINVAL;
119 		} else {
120 			sc->sc_smw.smw_period = smw->smw_period;
121 		}
122 		u_int tval = (sc->sc_smw.smw_period * 1000000) / 2;
123 		TIMER_WRITE(sc, TMR1_PTV_REG,
124 		    TMR_PTV_EN | TMR_PTV_PER | __SHIFTIN(tval, TMR_PTV_VAL));
125 		TIMER_WRITE(sc, TMR1_PCR_REG, TMR_PCR_INTR_CLR);
126 		tegra_car_wdt_enable(1, true);
127 	}
128 
129 	return 0;
130 }
131 
132 static int
133 tegra_timer_wdt_tickle(struct sysmon_wdog *smw)
134 {
135 	struct tegra_timer_softc * const sc = smw->smw_cookie;
136 
137 	TIMER_WRITE(sc, TMR1_PCR_REG, TMR_PCR_INTR_CLR);
138 
139 	return 0;
140 }
141