diff options
Diffstat (limited to 'sys/arm/at91/at91_rst.c')
| -rw-r--r-- | sys/arm/at91/at91_rst.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/sys/arm/at91/at91_rst.c b/sys/arm/at91/at91_rst.c new file mode 100644 index 0000000..0e50b39 --- /dev/null +++ b/sys/arm/at91/at91_rst.c @@ -0,0 +1,215 @@ +/*- + * Copyright (c) 2010 Greg Ansley. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/bus.h> +#include <sys/kernel.h> +#include <sys/module.h> +#include <sys/rman.h> +#include <sys/systm.h> + +#include <machine/bus.h> + +#include <arm/at91/at91var.h> +#include <arm/at91/at91_rstreg.h> +#include <arm/at91/at91board.h> + +#define RST_TIMEOUT (5) /* Seconds to hold NRST for hard reset */ +#define RST_TICK (20) /* sample NRST at hz/RST_TICK intervals */ + +static int rst_intr(void *arg); + +static struct rst_softc { + struct resource *mem_res; /* Memory resource */ + struct resource *irq_res; /* IRQ resource */ + void *intrhand; /* Interrupt handle */ + struct callout tick_ch; /* Tick callout */ + device_t sc_dev; + u_int shutdown; /* Shutdown in progress */ +} *rst_sc; + +static inline uint32_t +RD4(struct rst_softc *sc, bus_size_t off) +{ + + return (bus_read_4(sc->mem_res, off)); +} + +static inline void +WR4(struct rst_softc *sc, bus_size_t off, uint32_t val) +{ + + bus_write_4(sc->mem_res, off, val); +} + +static int +at91_rst_probe(device_t dev) +{ + + if (at91_is_sam9()) { + device_set_desc(dev, "AT91SAM9 Reset Controller"); + return (0); + } + return (ENXIO); +} + +static int +at91_rst_attach(device_t dev) +{ + struct rst_softc *sc; + const char *cause; + int rid, err; + + rst_sc = sc = device_get_softc(dev); + sc->sc_dev = dev; + + callout_init(&sc->tick_ch, 0); + + rid = 0; + sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, + RF_ACTIVE); + if (sc->mem_res == NULL) { + device_printf(dev, "could not allocate memory resources.\n"); + err = ENOMEM; + goto out; + } + rid = 0; + sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, + RF_ACTIVE | RF_SHAREABLE); + if (sc->irq_res == NULL) { + device_printf(dev, "could not allocate interrupt resources.\n"); + err = ENOMEM; + goto out; + } + + /* Activate the interrupt. */ + err = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_MISC | INTR_MPSAFE, + rst_intr, NULL, sc, &sc->intrhand); + if (err) + device_printf(dev, "could not establish interrupt handler.\n"); + + WR4(rst_sc, RST_MR, RST_MR_ERSTL(0xd) | RST_MR_URSIEN | RST_MR_KEY); + + switch (RD4(sc, RST_SR) & RST_SR_RST_MASK) { + case RST_SR_RST_POW: + cause = "Power On"; + break; + case RST_SR_RST_WAKE: + cause = "Wake Up"; + break; + case RST_SR_RST_WDT: + cause = "Watchdog"; + break; + case RST_SR_RST_SOFT: + cause = "Software Request"; + break; + case RST_SR_RST_USR: + cause = "External (User)"; + break; + default: + cause = "Unknown"; + break; + } + + device_printf(dev, "Reset cause: %s.\n", cause); + /* cpu_reset_addr = cpu_reset; */ + +out: + return (err); +} + +static void +rst_tick(void *argp) +{ + struct rst_softc *sc = argp; + + if (sc->shutdown++ >= RST_TIMEOUT * RST_TICK) { + /* User released the button in morre than RST_TIMEOUT */ + cpu_reset(); + } else if ((RD4(sc, RST_SR) & RST_SR_NRSTL)) { + /* User released the button in less than RST_TIMEOUT */ + sc->shutdown = 0; + device_printf(sc->sc_dev, "shutting down...\n"); + shutdown_nice(0); + } else { + callout_reset(&sc->tick_ch, hz/RST_TICK, rst_tick, sc); + } +} + +static int +rst_intr(void *argp) +{ + struct rst_softc *sc = argp; + + if (RD4(sc, RST_SR) & RST_SR_URSTS) { + if (sc->shutdown == 0) + callout_reset(&sc->tick_ch, hz/RST_TICK, rst_tick, sc); + return (FILTER_HANDLED); + } + return (FILTER_STRAY); +} + +static device_method_t at91_rst_methods[] = { + DEVMETHOD(device_probe, at91_rst_probe), + DEVMETHOD(device_attach, at91_rst_attach), + {0,0}, +}; + +static driver_t at91_rst_driver = { + "at91_rst", + at91_rst_methods, + sizeof(struct rst_softc), +}; + +static devclass_t at91_rst_devclass; + +DRIVER_MODULE(at91_rst, atmelarm, at91_rst_driver, at91_rst_devclass, 0, 0); + +void cpu_reset_sam9g20(void) __attribute__((weak)); +void cpu_reset_sam9g20(void) {} + +void +cpu_reset(void) +{ + + if (rst_sc) { + if (at91_cpu_is(AT91_CPU_SAM9G20)) + cpu_reset_sam9g20(); + + WR4(rst_sc, RST_MR, + RST_MR_ERSTL(0xd) | RST_MR_URSTEN | RST_MR_KEY); + + WR4(rst_sc, RST_CR, + RST_CR_PROCRST | + RST_CR_PERRST | + RST_CR_EXTRST | + RST_CR_KEY); + } + + for(;;) ; +} |
