xref: /netbsd-src/sys/arch/arm/nvidia/tegra_timer.c (revision 63aea4bd5b445e491ff0389fe27ec78b3099dba3)
1 /* $NetBSD: tegra_timer.c,v 1.2 2015/12/13 17:39:19 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 1.2 2015/12/13 17:39:19 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 #include <dev/fdt/fdtvar.h>
47 
48 #define TEGRA_TIMER_WDOG_PERIOD_DEFAULT	10
49 
50 static int	tegra_timer_match(device_t, cfdata_t, void *);
51 static void	tegra_timer_attach(device_t, device_t, void *);
52 
53 struct tegra_timer_softc {
54 	device_t		sc_dev;
55 	bus_space_tag_t		sc_bst;
56 	bus_space_handle_t	sc_bsh;
57 
58 	struct sysmon_wdog	sc_smw;
59 };
60 
61 static int	tegra_timer_wdt_setmode(struct sysmon_wdog *);
62 static int	tegra_timer_wdt_tickle(struct sysmon_wdog *);
63 
64 CFATTACH_DECL_NEW(tegra_timer, sizeof(struct tegra_timer_softc),
65 	tegra_timer_match, tegra_timer_attach, NULL, NULL);
66 
67 #define TIMER_READ(sc, reg)			\
68     bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
69 #define TIMER_WRITE(sc, reg, val)		\
70     bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
71 #define TIMER_SET_CLEAR(sc, reg, set, clr)	\
72     tegra_reg_set_clear((sc)->sc_bst, (sc)->sc_bsh, (reg), (set), (clr))
73 
74 static int
75 tegra_timer_match(device_t parent, cfdata_t cf, void *aux)
76 {
77 	const char * const compatible[] = { "nvidia,tegra124-timer", NULL };
78 	struct fdt_attach_args * const faa = aux;
79 
80 	return of_match_compatible(faa->faa_phandle, compatible);
81 }
82 
83 static void
84 tegra_timer_attach(device_t parent, device_t self, void *aux)
85 {
86 	struct tegra_timer_softc * const sc = device_private(self);
87 	struct fdt_attach_args * const faa = aux;
88 	bus_addr_t addr;
89 	bus_size_t size;
90 	int error;
91 
92 	if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) {
93 		aprint_error(": couldn't get registers\n");
94 		return;
95 	}
96 
97 	sc->sc_dev = self;
98 	sc->sc_bst = faa->faa_bst;
99 	error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
100 	if (error) {
101 		aprint_error(": couldn't map %#llx: %d", (uint64_t)addr, error);
102 		return;
103 	}
104 
105 	aprint_naive("\n");
106 	aprint_normal(": Timers\n");
107 
108 	sc->sc_smw.smw_name = device_xname(self);
109 	sc->sc_smw.smw_cookie = sc;
110 	sc->sc_smw.smw_setmode = tegra_timer_wdt_setmode;
111 	sc->sc_smw.smw_tickle = tegra_timer_wdt_tickle;
112 	sc->sc_smw.smw_period = TEGRA_TIMER_WDOG_PERIOD_DEFAULT;
113 
114 	aprint_normal_dev(self, "default watchdog period is %u seconds\n",
115 	    sc->sc_smw.smw_period);
116 
117 	if (sysmon_wdog_register(&sc->sc_smw) != 0)
118 		aprint_error_dev(self, "couldn't register with sysmon\n");
119 }
120 
121 static int
122 tegra_timer_wdt_setmode(struct sysmon_wdog *smw)
123 {
124 	struct tegra_timer_softc * const sc = smw->smw_cookie;
125 
126 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
127 		TIMER_SET_CLEAR(sc, TMR1_PTV_REG, 0, TMR_PTV_EN);
128 		tegra_car_wdt_enable(1, false);
129 	} else {
130 		if (smw->smw_period == WDOG_PERIOD_DEFAULT) {
131 			sc->sc_smw.smw_period = TEGRA_TIMER_WDOG_PERIOD_DEFAULT;
132 		} else if (smw->smw_period == 0 || smw->smw_period > 1000) {
133 			return EINVAL;
134 		} else {
135 			sc->sc_smw.smw_period = smw->smw_period;
136 		}
137 		u_int tval = (sc->sc_smw.smw_period * 1000000) / 2;
138 		TIMER_WRITE(sc, TMR1_PTV_REG,
139 		    TMR_PTV_EN | TMR_PTV_PER | __SHIFTIN(tval, TMR_PTV_VAL));
140 		TIMER_WRITE(sc, TMR1_PCR_REG, TMR_PCR_INTR_CLR);
141 		tegra_car_wdt_enable(1, true);
142 	}
143 
144 	return 0;
145 }
146 
147 static int
148 tegra_timer_wdt_tickle(struct sysmon_wdog *smw)
149 {
150 	struct tegra_timer_softc * const sc = smw->smw_cookie;
151 
152 	TIMER_WRITE(sc, TMR1_PCR_REG, TMR_PCR_INTR_CLR);
153 
154 	return 0;
155 }
156