LXR qemu/hw/misc/imx7

   1/*
   2 * IMX7 Secure Non-Volatile Storage
   3 *
   4 * Copyright (c) 2018, Impinj, Inc.
   5 *
   6 * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
   7 *
   8 * This work is licensed under the terms of the GNU GPL, version 2 or later.
   9 * See the COPYING file in the top-level directory.
  10 *
  11 * Bare minimum emulation code needed to support being able to shut
  12 * down linux guest gracefully.
  13 */
  14
  15#include "qemu/osdep.h"
  16#include "hw/misc/imx7_snvs.h"
  17#include "qemu/log.h"
  18#include "qemu/module.h"
  19#include "sysemu/runstate.h"
  20
  21static uint64_t imx7_snvs_read(void *opaque, hwaddr offset, unsigned size)
  22{
  23    return 0;
  24}
  25
  26static void imx7_snvs_write(void *opaque, hwaddr offset,
  27                            uint64_t v, unsigned size)
  28{
  29    const uint32_t value = v;
  30    const uint32_t mask  = SNVS_LPCR_TOP | SNVS_LPCR_DP_EN;
  31
  32    if (offset == SNVS_LPCR && ((value & mask) == mask)) {
  33        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
  34    }
  35}
  36
  37static const struct MemoryRegionOps imx7_snvs_ops = {
  38    .read = imx7_snvs_read,
  39    .write = imx7_snvs_write,
  40    .endianness = DEVICE_NATIVE_ENDIAN,
  41    .impl = {
  42        /*
  43         * Our device would not work correctly if the guest was doing
  44         * unaligned access. This might not be a limitation on the real
  45         * device but in practice there is no reason for a guest to access
  46         * this device unaligned.
  47         */
  48        .min_access_size = 4,
  49        .max_access_size = 4,
  50        .unaligned = false,
  51    },
  52};
  53
  54static void imx7_snvs_init(Object *obj)
  55{
  56    SysBusDevice *sd = SYS_BUS_DEVICE(obj);
  57    IMX7SNVSState *s = IMX7_SNVS(obj);
  58
  59    memory_region_init_io(&s->mmio, obj, &imx7_snvs_ops, s,
  60                          TYPE_IMX7_SNVS, 0x1000);
  61
  62    sysbus_init_mmio(sd, &s->mmio);
  63}
  64
  65static void imx7_snvs_class_init(ObjectClass *klass, void *data)
  66{
  67    DeviceClass *dc = DEVICE_CLASS(klass);
  68
  69    dc->desc  = "i.MX7 Secure Non-Volatile Storage Module";
  70}
  71
  72static const TypeInfo imx7_snvs_info = {
  73    .name          = TYPE_IMX7_SNVS,
  74    .parent        = TYPE_SYS_BUS_DEVICE,
  75    .instance_size = sizeof(IMX7SNVSState),
  76    .instance_init = imx7_snvs_init,
  77    .class_init    = imx7_snvs_class_init,
  78};
  79
  80static void imx7_snvs_register_type(void)
  81{
  82    type_register_static(&imx7_snvs_info);
  83}
  84type_init(imx7_snvs_register_type)
  85