tegra_timer.c revision 1.2 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 (at) 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