LXR qemu/hw/misc/sbsa

   1/*
   2 * ARM SBSA Reference Platform Embedded Controller
   3 *
   4 * A device to allow PSCI running in the secure side of sbsa-ref machine
   5 * to communicate platform power states to qemu.
   6 *
   7 * Copyright (c) 2020 Nuvia Inc
   8 * Written by Graeme Gregory <graeme@nuviainc.com>
   9 *
  10 * SPDX-License-Identifier: GPL-2.0-or-later
  11 */
  12
  13#include "qemu/osdep.h"
  14#include "qemu-common.h"
  15#include "qemu/log.h"
  16#include "hw/sysbus.h"
  17#include "sysemu/runstate.h"
  18
  19typedef struct {
  20    SysBusDevice parent_obj;
  21    MemoryRegion iomem;
  22} SECUREECState;
  23
  24#define TYPE_SBSA_EC      "sbsa-ec"
  25#define SECURE_EC(obj) OBJECT_CHECK(SECUREECState, (obj), TYPE_SBSA_EC)
  26
  27enum sbsa_ec_powerstates {
  28    SBSA_EC_CMD_POWEROFF = 0x01,
  29    SBSA_EC_CMD_REBOOT = 0x02,
  30};
  31
  32static uint64_t sbsa_ec_read(void *opaque, hwaddr offset, unsigned size)
  33{
  34    /* No use for this currently */
  35    qemu_log_mask(LOG_GUEST_ERROR, "sbsa-ec: no readable registers");
  36    return 0;
  37}
  38
  39static void sbsa_ec_write(void *opaque, hwaddr offset,
  40                     uint64_t value, unsigned size)
  41{
  42    if (offset == 0) { /* PSCI machine power command register */
  43        switch (value) {
  44        case SBSA_EC_CMD_POWEROFF:
  45            qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
  46            break;
  47        case SBSA_EC_CMD_REBOOT:
  48            qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
  49            break;
  50        default:
  51            qemu_log_mask(LOG_GUEST_ERROR,
  52                          "sbsa-ec: unknown power command");
  53        }
  54    } else {
  55        qemu_log_mask(LOG_GUEST_ERROR, "sbsa-ec: unknown EC register");
  56    }
  57}
  58
  59static const MemoryRegionOps sbsa_ec_ops = {
  60    .read = sbsa_ec_read,
  61    .write = sbsa_ec_write,
  62    .endianness = DEVICE_NATIVE_ENDIAN,
  63    .valid.min_access_size = 4,
  64    .valid.max_access_size = 4,
  65};
  66
  67static void sbsa_ec_init(Object *obj)
  68{
  69    SECUREECState *s = SECURE_EC(obj);
  70    SysBusDevice *dev = SYS_BUS_DEVICE(obj);
  71
  72    memory_region_init_io(&s->iomem, obj, &sbsa_ec_ops, s, "sbsa-ec",
  73                          0x1000);
  74    sysbus_init_mmio(dev, &s->iomem);
  75}
  76
  77static void sbsa_ec_class_init(ObjectClass *klass, void *data)
  78{
  79    DeviceClass *dc = DEVICE_CLASS(klass);
  80
  81    /* No vmstate or reset required: device has no internal state */
  82    dc->user_creatable = false;
  83}
  84
  85static const TypeInfo sbsa_ec_info = {
  86    .name          = TYPE_SBSA_EC,
  87    .parent        = TYPE_SYS_BUS_DEVICE,
  88    .instance_size = sizeof(SECUREECState),
  89    .instance_init = sbsa_ec_init,
  90    .class_init    = sbsa_ec_class_init,
  91};
  92
  93static void sbsa_ec_register_type(void)
  94{
  95    type_register_static(&sbsa_ec_info);
  96}
  97
  98type_init(sbsa_ec_register_type);
  99