xref: /netbsd-src/sys/arch/arm/nvidia/tegra_timer.c (revision 7330f729ccf0bd976a06f95fad452fe774fc7fd1)
1 /* $NetBSD: tegra_timer.c,v 1.11 2019/10/13 06:11:31 skrll 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 1.11 2019/10/13 06:11:31 skrll 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[] = {
78 		"nvidia,tegra210-timer",
79 		"nvidia,tegra124-timer",
80 		"nvidia,tegra20-timer",
81 		NULL
82 	};
83 	struct fdt_attach_args * const faa = aux;
84 
85 	return of_match_compatible(faa->faa_phandle, compatible);
86 }
87 
88 static void
89 tegra_timer_attach(device_t parent, device_t self, void *aux)
90 {
91 	struct tegra_timer_softc * const sc = device_private(self);
92 	struct fdt_attach_args * const faa = aux;
93 	bus_addr_t addr;
94 	bus_size_t size;
95 	int error;
96 
97 	if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) {
98 		aprint_error(": couldn't get registers\n");
99 		return;
100 	}
101 
102 	sc->sc_dev = self;
103 	sc->sc_bst = faa->faa_bst;
104 	error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
105 	if (error) {
106 		aprint_error(": couldn't map %#" PRIxBUSADDR ": %d", addr, error);
107 		return;
108 	}
109 
110 	aprint_naive("\n");
111 	aprint_normal(": Timers\n");
112 
113 	sc->sc_smw.smw_name = device_xname(self);
114 	sc->sc_smw.smw_cookie = sc;
115 	sc->sc_smw.smw_setmode = tegra_timer_wdt_setmode;
116 	sc->sc_smw.smw_tickle = tegra_timer_wdt_tickle;
117 	sc->sc_smw.smw_period = TEGRA_TIMER_WDOG_PERIOD_DEFAULT;
118 
119 	aprint_normal_dev(self,
120 	    "default watchdog period is %u seconds\n",
121 	    sc->sc_smw.smw_period);
122 
123 	if (sysmon_wdog_register(&sc->sc_smw) != 0) {
124 		aprint_error_dev(self,
125 		    "couldn't register with sysmon\n");
126 	}
127 }
128 
129 static int
130 tegra_timer_wdt_setmode(struct sysmon_wdog *smw)
131 {
132 	struct tegra_timer_softc * const sc = smw->smw_cookie;
133 
134 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
135 		TIMER_SET_CLEAR(sc, TMR1_PTV_REG, 0, TMR_PTV_EN);
136 	} else {
137 		if (smw->smw_period == WDOG_PERIOD_DEFAULT) {
138 			sc->sc_smw.smw_period = TEGRA_TIMER_WDOG_PERIOD_DEFAULT;
139 		} else if (smw->smw_period == 0 || smw->smw_period > 1000) {
140 			return EINVAL;
141 		} else {
142 			sc->sc_smw.smw_period = smw->smw_period;
143 		}
144 		u_int tval = (sc->sc_smw.smw_period * 1000000) / 2;
145 		TIMER_WRITE(sc, TMR1_PTV_REG,
146 		    TMR_PTV_EN | TMR_PTV_PER | __SHIFTIN(tval, TMR_PTV_VAL));
147 		TIMER_WRITE(sc, TMR1_PCR_REG, TMR_PCR_INTR_CLR);
148 	}
149 
150 	return 0;
151 }
152 
153 static int
154 tegra_timer_wdt_tickle(struct sysmon_wdog *smw)
155 {
156 	struct tegra_timer_softc * const sc = smw->smw_cookie;
157 
158 	TIMER_WRITE(sc, TMR1_PCR_REG, TMR_PCR_INTR_CLR);
159 
160 	return 0;
161 }
162 
163 void
164 tegra_timer_delay(u_int us)
165 {
166 	static bool timerus_configured = false;
167 	extern struct bus_space arm_generic_bs_tag;
168 	bus_space_tag_t bst = &arm_generic_bs_tag;
169 	bus_space_handle_t bsh;
170 
171 	bus_space_subregion(bst, tegra_ppsb_bsh, TEGRA_TIMER_OFFSET,
172 	    TEGRA_TIMER_SIZE, &bsh);
173 
174 	if (__predict_false(timerus_configured == false)) {
175 		/* clk_m frequency 12 MHz */
176 		bus_space_write_4(bst, bsh, TMRUS_USEC_CFG_REG, 0xb);
177 		timerus_configured = true;
178 	}
179 
180 	u_int nus = 0;
181 	u_int us_prev = bus_space_read_4(bst, bsh, TMRUS_CNTR_1US_REG);
182 
183 	while (nus < us) {
184 		const u_int us_cur = bus_space_read_4(bst, bsh,
185 		    TMRUS_CNTR_1US_REG);
186 		if (us_cur < us_prev) {
187 			nus += (0xffffffff - us_prev) + us_cur;
188 		} else {
189 			nus += (us_cur - us_prev);
190 		}
191 		us_prev = us_cur;
192 	}
193 }
194