tegra_timer.c revision 1.4.2.1 1 /* $NetBSD: tegra_timer.c,v 1.4.2.1 2017/04/26 02:53:01 pgoyette 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 1.4.2.1 2017/04/26 02:53:01 pgoyette 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,
115 "default watchdog period is %u seconds\n",
116 sc->sc_smw.smw_period);
117
118 if (sysmon_wdog_register(&sc->sc_smw) != 0) {
119 aprint_error_dev(self,
120 "couldn't register with sysmon\n");
121 }
122 }
123
124 static int
125 tegra_timer_wdt_setmode(struct sysmon_wdog *smw)
126 {
127 struct tegra_timer_softc * const sc = smw->smw_cookie;
128
129 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
130 TIMER_SET_CLEAR(sc, TMR1_PTV_REG, 0, TMR_PTV_EN);
131 } else {
132 if (smw->smw_period == WDOG_PERIOD_DEFAULT) {
133 sc->sc_smw.smw_period = TEGRA_TIMER_WDOG_PERIOD_DEFAULT;
134 } else if (smw->smw_period == 0 || smw->smw_period > 1000) {
135 return EINVAL;
136 } else {
137 sc->sc_smw.smw_period = smw->smw_period;
138 }
139 u_int tval = (sc->sc_smw.smw_period * 1000000) / 2;
140 TIMER_WRITE(sc, TMR1_PTV_REG,
141 TMR_PTV_EN | TMR_PTV_PER | __SHIFTIN(tval, TMR_PTV_VAL));
142 TIMER_WRITE(sc, TMR1_PCR_REG, TMR_PCR_INTR_CLR);
143 }
144
145 return 0;
146 }
147
148 static int
149 tegra_timer_wdt_tickle(struct sysmon_wdog *smw)
150 {
151 struct tegra_timer_softc * const sc = smw->smw_cookie;
152
153 TIMER_WRITE(sc, TMR1_PCR_REG, TMR_PCR_INTR_CLR);
154
155 return 0;
156 }
157
158 void
159 delay(u_int us)
160 {
161 static bool timerus_configured = false;
162 bus_space_tag_t bst = &armv7_generic_bs_tag;
163 bus_space_handle_t bsh;
164
165 bus_space_subregion(bst, tegra_ppsb_bsh, TEGRA_TIMER_OFFSET,
166 TEGRA_TIMER_SIZE, &bsh);
167
168 if (__predict_false(timerus_configured == false)) {
169 /* clk_m frequency 12 MHz */
170 bus_space_write_4(bst, bsh, TMRUS_USEC_CFG_REG, 0xb);
171 timerus_configured = true;
172 }
173
174 u_int nus = 0;
175 u_int us_prev = bus_space_read_4(bst, bsh, TMRUS_CNTR_1US_REG);
176
177 while (nus < us) {
178 const u_int us_cur = bus_space_read_4(bst, bsh,
179 TMRUS_CNTR_1US_REG);
180 if (us_cur < us_prev) {
181 nus += (0xffffffff - us_prev) + us_cur;
182 } else {
183 nus += (us_cur - us_prev);
184 }
185 us_prev = us_cur;
186 }
187 }
188