1/*-
2 * Copyright (c) 2010 Greg Ansley. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26#include <sys/cdefs.h>
27__FBSDID("$FreeBSD: stable/10/sys/arm/at91/at91_rst.c 238369 2012-07-11 17:11:07Z imp $");
28
29#include <sys/param.h>
30#include <sys/bus.h>
31#include <sys/kernel.h>
32#include <sys/module.h>
33#include <sys/rman.h>
34#include <sys/systm.h>
35
36#include <machine/bus.h>
37
38#include <arm/at91/at91var.h>
39#include <arm/at91/at91_rstreg.h>
40#include <arm/at91/at91board.h>
41
42#define RST_TIMEOUT (5) /* Seconds to hold NRST for hard reset */
43#define RST_TICK (20) /* sample NRST at hz/RST_TICK intervals */
44
45static int at91_rst_intr(void *arg);
46
47static struct at91_rst_softc {
48 struct resource *mem_res; /* Memory resource */
49 struct resource *irq_res; /* IRQ resource */
50 void *intrhand; /* Interrupt handle */
51 struct callout tick_ch; /* Tick callout */
52 device_t sc_dev;
53 u_int shutdown; /* Shutdown in progress */
54} *at91_rst_sc;
55
56static inline uint32_t
57RD4(struct at91_rst_softc *sc, bus_size_t off)
58{
59
60 return (bus_read_4(sc->mem_res, off));
61}
62
63static inline void
64WR4(struct at91_rst_softc *sc, bus_size_t off, uint32_t val)
65{
66
67 bus_write_4(sc->mem_res, off, val);
68}
69
70void cpu_reset_sam9g20(void) __attribute__((weak));
71void cpu_reset_sam9g20(void) {}
72
73void
74at91_rst_cpu_reset(void)
75{
76
77 if (at91_rst_sc) {
78 cpu_reset_sam9g20(); /* May be null */
79
80 WR4(at91_rst_sc, RST_MR,
81 RST_MR_ERSTL(0xd) | RST_MR_URSTEN | RST_MR_KEY);
82
83 WR4(at91_rst_sc, RST_CR,
84 RST_CR_PROCRST |
85 RST_CR_PERRST |
86 RST_CR_EXTRST |
87 RST_CR_KEY);
88 }
89 while(1)
90 continue;
91}
92
93static int
94at91_rst_probe(device_t dev)
95{
96
97 device_set_desc(dev, "AT91SAM9 Reset Controller");
98 return (0);
99}
100
101static int
102at91_rst_attach(device_t dev)
103{
104 struct at91_rst_softc *sc;
105 const char *cause;
106 int rid, err;
107
108 at91_rst_sc = sc = device_get_softc(dev);
109 sc->sc_dev = dev;
110
111 callout_init(&sc->tick_ch, 0);
112
113 rid = 0;
114 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
115 RF_ACTIVE);
116 if (sc->mem_res == NULL) {
117 device_printf(dev, "could not allocate memory resources.\n");
118 err = ENOMEM;
119 goto out;
120 }
121 rid = 0;
122 sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
123 RF_ACTIVE | RF_SHAREABLE);
124 if (sc->irq_res == NULL) {
125 device_printf(dev, "could not allocate interrupt resources.\n");
126 err = ENOMEM;
127 goto out;
128 }
129
130 /* Activate the interrupt. */
131 err = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
132 at91_rst_intr, NULL, sc, &sc->intrhand);
133 if (err)
134 device_printf(dev, "could not establish interrupt handler.\n");
135
136 WR4(at91_rst_sc, RST_MR, RST_MR_ERSTL(0xd) | RST_MR_URSIEN | RST_MR_KEY);
137
138 switch (RD4(sc, RST_SR) & RST_SR_RST_MASK) {
139 case RST_SR_RST_POW:
140 cause = "Power On";
141 break;
142 case RST_SR_RST_WAKE:
143 cause = "Wake Up";
144 break;
145 case RST_SR_RST_WDT:
146 cause = "Watchdog";
147 break;
148 case RST_SR_RST_SOFT:
149 cause = "Software Request";
150 break;
151 case RST_SR_RST_USR:
152 cause = "External (User)";
153 break;
154 default:
155 cause = "Unknown";
156 break;
157 }
158
159 device_printf(dev, "Reset cause: %s.\n", cause);
160out:
161 return (err);
162}
163
164static void
165at91_rst_tick(void *argp)
166{
167 struct at91_rst_softc *sc = argp;
168
169 if (sc->shutdown++ >= RST_TIMEOUT * RST_TICK) {
170 /* User released the button in morre than RST_TIMEOUT */
171 cpu_reset();
172 } else if ((RD4(sc, RST_SR) & RST_SR_NRSTL)) {
173 /* User released the button in less than RST_TIMEOUT */
174 sc->shutdown = 0;
175 device_printf(sc->sc_dev, "shutting down...\n");
176 shutdown_nice(0);
177 } else {
178 callout_reset(&sc->tick_ch, hz/RST_TICK, at91_rst_tick, sc);
179 }
180}
181
182static int
183at91_rst_intr(void *argp)
184{
185 struct at91_rst_softc *sc = argp;
186
187 if (RD4(sc, RST_SR) & RST_SR_URSTS) {
188 if (sc->shutdown == 0)
189 callout_reset(&sc->tick_ch, hz/RST_TICK, at91_rst_tick, sc);
190 return (FILTER_HANDLED);
191 }
192 return (FILTER_STRAY);
193}
194
195static device_method_t at91_rst_methods[] = {
196 DEVMETHOD(device_probe, at91_rst_probe),
197 DEVMETHOD(device_attach, at91_rst_attach),
198 DEVMETHOD_END
199};
200
201static driver_t at91_rst_driver = {
202 "at91_rst",
203 at91_rst_methods,
204 sizeof(struct at91_rst_softc),
205};
206
207static devclass_t at91_rst_devclass;
208
209DRIVER_MODULE(at91_rst, atmelarm, at91_rst_driver, at91_rst_devclass, NULL,
210 NULL);