FreeBSD/Linux Kernel Cross Reference
sys/arm/xilinx/zy7_gpio.c

     /*-
      * Copyright (c) 2013 Thomas Skibo
      * 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 THE 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 THE 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.
     *
     * $FreeBSD$
     */
    
    /*
     * A GPIO driver for Xilinx Zynq-7000.
     *
     * The GPIO peripheral on Zynq allows controlling 114 general purpose I/Os.
     *
     * Pins 53-0 are sent to the MIO.  Any MIO pins not used by a PS peripheral are
     * available as a GPIO pin.  Pins 64-127 are sent to the PL (FPGA) section of
     * Zynq as EMIO signals.
     *
     * The hardware provides a way to use IOs as interrupt sources but the
     * gpio framework doesn't seem to have hooks for this.
     *
     * Reference: Zynq-7000 All Programmable SoC Technical Reference Manual.
     * (v1.4) November 16, 2012.  Xilinx doc UG585.  GPIO is covered in
     * chater 14.  Register definitions are in appendix B.19.
     */
    
    #include <sys/cdefs.h>
    __FBSDID("$FreeBSD$");
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/conf.h>
    #include <sys/bus.h>
    #include <sys/kernel.h>
    #include <sys/module.h>
    #include <sys/lock.h>
    #include <sys/mutex.h>
    #include <sys/resource.h>
    #include <sys/rman.h>
    #include <sys/gpio.h>
    
    #include <machine/bus.h>
    #include <machine/resource.h>
    #include <machine/stdarg.h>
    
    #include <dev/fdt/fdt_common.h>
    #include <dev/gpio/gpiobusvar.h>
    #include <dev/ofw/ofw_bus.h>
    #include <dev/ofw/ofw_bus_subr.h>
    
    #include "gpio_if.h"
    
    #define NUMBANKS        4
    #define MAXPIN          (32*NUMBANKS)
    
    #define MIO_PIN         0       /* pins 0-53 go to MIO */
    #define NUM_MIO_PINS    54
    #define EMIO_PIN        64      /* pins 64-127 go to PL */
    #define NUM_EMIO_PINS   64
    
    #define VALID_PIN(u)    (((u) >= MIO_PIN && (u) < MIO_PIN + NUM_MIO_PINS) || \
                             ((u) >= EMIO_PIN && (u) < EMIO_PIN + NUM_EMIO_PINS))
    
    #define ZGPIO_LOCK(sc)                  mtx_lock(&(sc)->sc_mtx)
    #define ZGPIO_UNLOCK(sc)                mtx_unlock(&(sc)->sc_mtx)
    #define ZGPIO_LOCK_INIT(sc) \
            mtx_init(&(sc)->sc_mtx, device_get_nameunit((sc)->dev), \
                "gpio", MTX_DEF)
    #define ZGPIO_LOCK_DESTROY(_sc) mtx_destroy(&_sc->sc_mtx);
    
    struct zy7_gpio_softc {
            device_t        dev;
            device_t        busdev;
            struct mtx      sc_mtx;
            struct resource *mem_res;       /* Memory resource */
    };
    
    #define WR4(sc, off, val)       bus_write_4((sc)->mem_res, (off), (val))
    #define RD4(sc, off)            bus_read_4((sc)->mem_res, (off))
    
   
   /* Xilinx Zynq-7000 GPIO register definitions:
    */
   #define ZY7_GPIO_MASK_DATA_LSW(b)       (0x0000+8*(b))  /* maskable wr lo */
   #define ZY7_GPIO_MASK_DATA_MSW(b)       (0x0004+8*(b))  /* maskable wr hi */
   #define ZY7_GPIO_DATA(b)                (0x0040+4*(b))  /* in/out data */
   #define ZY7_GPIO_DATA_RO(b)             (0x0060+4*(b))  /* input data */
   
   #define ZY7_GPIO_DIRM(b)                (0x0204+0x40*(b)) /* direction mode */
   #define ZY7_GPIO_OEN(b)                 (0x0208+0x40*(b)) /* output enable */
   #define ZY7_GPIO_INT_MASK(b)            (0x020c+0x40*(b)) /* int mask */
   #define ZY7_GPIO_INT_EN(b)              (0x0210+0x40*(b)) /* int enable */
   #define ZY7_GPIO_INT_DIS(b)             (0x0214+0x40*(b)) /* int disable */
   #define ZY7_GPIO_INT_STAT(b)            (0x0218+0x40*(b)) /* int status */
   #define ZY7_GPIO_INT_TYPE(b)            (0x021c+0x40*(b)) /* int type */
   #define ZY7_GPIO_INT_POLARITY(b)        (0x0220+0x40*(b)) /* int polarity */
   #define ZY7_GPIO_INT_ANY(b)             (0x0224+0x40*(b)) /* any edge */
   
   static device_t
   zy7_gpio_get_bus(device_t dev)
   {
           struct zy7_gpio_softc *sc;
   
           sc = device_get_softc(dev);
   
           return (sc->busdev);
   }
   
   static int
   zy7_gpio_pin_max(device_t dev, int *maxpin)
   {
   
           *maxpin = MAXPIN;
           return (0);
   }
   
   /* Get a specific pin's capabilities. */
   static int
   zy7_gpio_pin_getcaps(device_t dev, uint32_t pin, uint32_t *caps)
   {
   
           if (!VALID_PIN(pin))
                   return (EINVAL);
   
           *caps = (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
   
           return (0);
   }
   
   /* Get a specific pin's name. */
   static int
   zy7_gpio_pin_getname(device_t dev, uint32_t pin, char *name)
   {
   
           if (!VALID_PIN(pin))
                   return (EINVAL);
   
           if (pin < NUM_MIO_PINS) {
                   snprintf(name, GPIOMAXNAME, "MIO_%d", pin);
                   name[GPIOMAXNAME - 1] = '\0';
           } else {
                   snprintf(name, GPIOMAXNAME, "EMIO_%d", pin - EMIO_PIN);
                   name[GPIOMAXNAME - 1] = '\0';
           }
   
           return (0);
   }
   
   /* Get a specific pin's current in/out/tri state. */
   static int
   zy7_gpio_pin_getflags(device_t dev, uint32_t pin, uint32_t *flags)
   {
           struct zy7_gpio_softc *sc = device_get_softc(dev);
   
           if (!VALID_PIN(pin))
                   return (EINVAL);
   
           ZGPIO_LOCK(sc);
   
           if ((RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) & (1 << (pin & 31))) != 0) {
                   /* output */
                   if ((RD4(sc, ZY7_GPIO_OEN(pin >> 5)) & (1 << (pin & 31))) == 0)
                           *flags = (GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
                   else
                           *flags = GPIO_PIN_OUTPUT;
           } else
                   /* input */
                   *flags = GPIO_PIN_INPUT;
   
           ZGPIO_UNLOCK(sc);
   
           return (0);
   }
   
   /* Set a specific pin's in/out/tri state. */
   static int
   zy7_gpio_pin_setflags(device_t dev, uint32_t pin, uint32_t flags)
   {
           struct zy7_gpio_softc *sc = device_get_softc(dev);
   
           if (!VALID_PIN(pin))
                   return (EINVAL);
   
           ZGPIO_LOCK(sc);
   
           if ((flags & GPIO_PIN_OUTPUT) != 0) {
                   /* Output.  Set or reset OEN too. */
                   WR4(sc, ZY7_GPIO_DIRM(pin >> 5),
                       RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) | (1 << (pin & 31)));
   
                   if ((flags & GPIO_PIN_TRISTATE) != 0)
                           WR4(sc, ZY7_GPIO_OEN(pin >> 5),
                               RD4(sc, ZY7_GPIO_OEN(pin >> 5)) &
                               ~(1 << (pin & 31)));
                   else
                           WR4(sc, ZY7_GPIO_OEN(pin >> 5),
                               RD4(sc, ZY7_GPIO_OEN(pin >> 5)) |
                               (1 << (pin & 31)));
           } else {
                   /* Input.  Turn off OEN. */
                   WR4(sc, ZY7_GPIO_DIRM(pin >> 5),
                       RD4(sc, ZY7_GPIO_DIRM(pin >> 5)) & ~(1 << (pin & 31)));
                   WR4(sc, ZY7_GPIO_OEN(pin >> 5),
                       RD4(sc, ZY7_GPIO_OEN(pin >> 5)) & ~(1 << (pin & 31)));
           }
                   
           ZGPIO_UNLOCK(sc);
   
           return (0);
   }
   
   /* Set a specific output pin's value. */
   static int
   zy7_gpio_pin_set(device_t dev, uint32_t pin, unsigned int value)
   {
           struct zy7_gpio_softc *sc = device_get_softc(dev);
   
           if (!VALID_PIN(pin) || value > 1)
                   return (EINVAL);
   
           /* Fancy register tricks allow atomic set or reset. */
           if ((pin & 16) != 0)
                   WR4(sc, ZY7_GPIO_MASK_DATA_MSW(pin >> 5),
                       (0xffff0000 ^ (0x10000 << (pin & 15))) |
                       (value << (pin & 15)));
           else
                   WR4(sc, ZY7_GPIO_MASK_DATA_LSW(pin >> 5),
                       (0xffff0000 ^ (0x10000 << (pin & 15))) |
                       (value << (pin & 15)));
   
           return (0);
   }
   
   /* Get a specific pin's input value. */
   static int
   zy7_gpio_pin_get(device_t dev, uint32_t pin, unsigned int *value)
   {
           struct zy7_gpio_softc *sc = device_get_softc(dev);
   
           if (!VALID_PIN(pin))
                   return (EINVAL);
   
           *value = (RD4(sc, ZY7_GPIO_DATA_RO(pin >> 5)) >> (pin & 31)) & 1;
   
           return (0);
   }
   
   /* Toggle a pin's output value. */
   static int
   zy7_gpio_pin_toggle(device_t dev, uint32_t pin)
   {
           struct zy7_gpio_softc *sc = device_get_softc(dev);
   
           if (!VALID_PIN(pin))
                   return (EINVAL);
   
           ZGPIO_LOCK(sc);
   
           WR4(sc, ZY7_GPIO_DATA(pin >> 5),
               RD4(sc, ZY7_GPIO_DATA(pin >> 5)) ^ (1 << (pin & 31)));
   
           ZGPIO_UNLOCK(sc);
   
           return (0);
   }
   
   static int
   zy7_gpio_probe(device_t dev)
   {
   
           if (!ofw_bus_status_okay(dev))
                   return (ENXIO);
   
           if (!ofw_bus_is_compatible(dev, "xlnx,zy7_gpio"))
                   return (ENXIO);
   
           device_set_desc(dev, "Zynq-7000 GPIO driver");
           return (0);
   }
   
   static int zy7_gpio_detach(device_t dev);
   
   static int
   zy7_gpio_attach(device_t dev)
   {
           struct zy7_gpio_softc *sc = device_get_softc(dev);
           int rid;
   
           sc->dev = dev;
   
           ZGPIO_LOCK_INIT(sc);
   
           /* Allocate memory. */
           rid = 0;
           sc->mem_res = bus_alloc_resource_any(dev,
                        SYS_RES_MEMORY, &rid, RF_ACTIVE);
           if (sc->mem_res == NULL) {
                   device_printf(dev, "Can't allocate memory for device");
                   zy7_gpio_detach(dev);
                   return (ENOMEM);
           }
   
           sc->busdev = gpiobus_attach_bus(dev);
           if (sc->busdev == NULL) {
                   zy7_gpio_detach(dev);
                   return (ENOMEM);
           }
   
           return (0);
   }
   
   static int
   zy7_gpio_detach(device_t dev)
   {
           struct zy7_gpio_softc *sc = device_get_softc(dev);
   
           gpiobus_detach_bus(dev);
   
           if (sc->mem_res != NULL) {
                   /* Release memory resource. */
                   bus_release_resource(dev, SYS_RES_MEMORY,
                                        rman_get_rid(sc->mem_res), sc->mem_res);
           }
   
           ZGPIO_LOCK_DESTROY(sc);
   
           return (0);
   }
   
   static device_method_t zy7_gpio_methods[] = {
           /* device_if */
           DEVMETHOD(device_probe,         zy7_gpio_probe),
           DEVMETHOD(device_attach,        zy7_gpio_attach),
           DEVMETHOD(device_detach,        zy7_gpio_detach),
   
           /* GPIO protocol */
           DEVMETHOD(gpio_get_bus,         zy7_gpio_get_bus),
           DEVMETHOD(gpio_pin_max,         zy7_gpio_pin_max),
           DEVMETHOD(gpio_pin_getname,     zy7_gpio_pin_getname),
           DEVMETHOD(gpio_pin_getflags,    zy7_gpio_pin_getflags),
           DEVMETHOD(gpio_pin_getcaps,     zy7_gpio_pin_getcaps),
           DEVMETHOD(gpio_pin_setflags,    zy7_gpio_pin_setflags),
           DEVMETHOD(gpio_pin_get,         zy7_gpio_pin_get),
           DEVMETHOD(gpio_pin_set,         zy7_gpio_pin_set),
           DEVMETHOD(gpio_pin_toggle,      zy7_gpio_pin_toggle),
   
           DEVMETHOD_END
   };
   
   static driver_t zy7_gpio_driver = {
           "gpio",
           zy7_gpio_methods,
           sizeof(struct zy7_gpio_softc),
   };
   static devclass_t zy7_gpio_devclass;
   
   DRIVER_MODULE(zy7_gpio, simplebus, zy7_gpio_driver, zy7_gpio_devclass, \
                 NULL, NULL);

Cache object: c5c478423a79388c7ad09f7d32dd32ac