2 * Copyright (c) 2010 Greg Ansley. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
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.
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
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
29 #include <sys/param.h>
31 #include <sys/kernel.h>
32 #include <sys/module.h>
34 #include <sys/systm.h>
36 #include <machine/bus.h>
38 #include <arm/at91/at91var.h>
39 #include <arm/at91/at91_rstreg.h>
40 #include <arm/at91/at91board.h>
42 #define RST_TIMEOUT (5) /* Seconds to hold NRST for hard reset */
43 #define RST_TICK (20) /* sample NRST at hz/RST_TICK intervals */
45 static int at91_rst_intr(void *arg);
47 static 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 */
53 u_int shutdown; /* Shutdown in progress */
56 static inline uint32_t
57 RD4(struct at91_rst_softc *sc, bus_size_t off)
60 return (bus_read_4(sc->mem_res, off));
64 WR4(struct at91_rst_softc *sc, bus_size_t off, uint32_t val)
67 bus_write_4(sc->mem_res, off, val);
70 void cpu_reset_sam9g20(void) __attribute__((weak));
71 void cpu_reset_sam9g20(void) {}
74 at91_rst_cpu_reset(void)
78 cpu_reset_sam9g20(); /* May be null */
80 WR4(at91_rst_sc, RST_MR,
81 RST_MR_ERSTL(0xd) | RST_MR_URSTEN | RST_MR_KEY);
83 WR4(at91_rst_sc, RST_CR,
94 at91_rst_probe(device_t dev)
97 device_set_desc(dev, "AT91SAM9 Reset Controller");
102 at91_rst_attach(device_t dev)
104 struct at91_rst_softc *sc;
108 at91_rst_sc = sc = device_get_softc(dev);
111 callout_init(&sc->tick_ch, 0);
114 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
116 if (sc->mem_res == NULL) {
117 device_printf(dev, "could not allocate memory resources.\n");
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");
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);
134 device_printf(dev, "could not establish interrupt handler.\n");
136 WR4(at91_rst_sc, RST_MR, RST_MR_ERSTL(0xd) | RST_MR_URSIEN | RST_MR_KEY);
138 switch (RD4(sc, RST_SR) & RST_SR_RST_MASK) {
142 case RST_SR_RST_WAKE:
148 case RST_SR_RST_SOFT:
149 cause = "Software Request";
152 cause = "External (User)";
159 device_printf(dev, "Reset cause: %s.\n", cause);
165 at91_rst_tick(void *argp)
167 struct at91_rst_softc *sc = argp;
169 if (sc->shutdown++ >= RST_TIMEOUT * RST_TICK) {
170 /* User released the button in morre than RST_TIMEOUT */
172 } else if ((RD4(sc, RST_SR) & RST_SR_NRSTL)) {
173 /* User released the button in less than RST_TIMEOUT */
175 device_printf(sc->sc_dev, "shutting down...\n");
178 callout_reset(&sc->tick_ch, hz/RST_TICK, at91_rst_tick, sc);
183 at91_rst_intr(void *argp)
185 struct at91_rst_softc *sc = argp;
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);
192 return (FILTER_STRAY);
195 static device_method_t at91_rst_methods[] = {
196 DEVMETHOD(device_probe, at91_rst_probe),
197 DEVMETHOD(device_attach, at91_rst_attach),
201 static driver_t at91_rst_driver = {
204 sizeof(struct at91_rst_softc),
207 static devclass_t at91_rst_devclass;
209 DRIVER_MODULE(at91_rst, atmelarm, at91_rst_driver, at91_rst_devclass, NULL,