hw/gpio/gpio_pwr.c

   1 /*
   2  * GPIO qemu power controller
   3  *
   4  * Copyright (c) 2020 Linaro Limited
   5  *
   6  * Author: Maxim Uvarov <maxim.uvarov@linaro.org>
   7  *
   8  * Virtual gpio driver which can be used on top of pl061
   9  * to reboot and shutdown qemu virtual machine. One of use
  10  * case is gpio driver for secure world application (ARM
  11  * Trusted Firmware.).
  12  *
  13  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  14  * See the COPYING file in the top-level directory.
  15  * SPDX-License-Identifier: GPL-2.0-or-later
  16  */
  17
  18 /*
  19  * QEMU interface:
  20  * two named input GPIO lines:
  21  *   'reset' : when asserted, trigger system reset
  22  *   'shutdown' : when asserted, trigger system shutdown
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "hw/sysbus.h"
  27 #include "sysemu/runstate.h"
  28
  29 #define TYPE_GPIOPWR "gpio-pwr"
  30 OBJECT_DECLARE_SIMPLE_TYPE(GPIO_PWR_State, GPIOPWR)
  31
  32 struct GPIO_PWR_State {
  33     SysBusDevice parent_obj;
  34 };
  35
  36 static void gpio_pwr_reset(void *opaque, int n, int level)
  37 {
  38     if (level) {
  39         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
  40     }
  41 }
  42
  43 static void gpio_pwr_shutdown(void *opaque, int n, int level)
  44 {
  45     if (level) {
  46         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
  47     }
  48 }
  49
  50 static void gpio_pwr_init(Object *obj)
  51 {
  52     DeviceState *dev = DEVICE(obj);
  53
  54     qdev_init_gpio_in_named(dev, gpio_pwr_reset, "reset", 1);
  55     qdev_init_gpio_in_named(dev, gpio_pwr_shutdown, "shutdown", 1);
  56 }
  57
  58 static const TypeInfo gpio_pwr_info = {
  59     .name          = TYPE_GPIOPWR,
  60     .parent        = TYPE_SYS_BUS_DEVICE,
  61     .instance_size = sizeof(GPIO_PWR_State),
  62     .instance_init = gpio_pwr_init,
  63 };
  64
  65 static void gpio_pwr_register_types(void)
  66 {
  67     type_register_static(&gpio_pwr_info);
  68 }
  69
  70 type_init(gpio_pwr_register_types)