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/module.h"
  18#include "sysemu/runstate.h"
  19
  20static uint64_t imx7_snvs_read(void *opaque, hwaddr offset, unsigned size)
  21{
  22    return 0;
  23}
  24
  25static void imx7_snvs_write(void *opaque, hwaddr offset,
  26                            uint64_t v, unsigned size)
  27{
  28    const uint32_t value = v;
  29    const uint32_t mask  = SNVS_LPCR_TOP | SNVS_LPCR_DP_EN;
  30
  31    if (offset == SNVS_LPCR && ((value & mask) == mask)) {
  32        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
  33    }
  34}
  35
  36static const struct MemoryRegionOps imx7_snvs_ops = {
  37    .read = imx7_snvs_read,
  38    .write = imx7_snvs_write,
  39    .endianness = DEVICE_NATIVE_ENDIAN,
  40    .impl = {
  41        /*
  42         * Our device would not work correctly if the guest was doing
  43         * unaligned access. This might not be a limitation on the real
  44         * device but in practice there is no reason for a guest to access
  45         * this device unaligned.
  46         */
  47        .min_access_size = 4,
  48        .max_access_size = 4,
  49        .unaligned = false,
  50    },
  51};
  52
  53static void imx7_snvs_init(Object *obj)
  54{
  55    SysBusDevice *sd = SYS_BUS_DEVICE(obj);
  56    IMX7SNVSState *s = IMX7_SNVS(obj);
  57
  58    memory_region_init_io(&s->mmio, obj, &imx7_snvs_ops, s,
  59                          TYPE_IMX7_SNVS, 0x1000);
  60
  61    sysbus_init_mmio(sd, &s->mmio);
  62}
  63
  64static void imx7_snvs_class_init(ObjectClass *klass, void *data)
  65{
  66    DeviceClass *dc = DEVICE_CLASS(klass);
  67
  68    dc->desc  = "i.MX7 Secure Non-Volatile Storage Module";
  69}
  70
  71static const TypeInfo imx7_snvs_info = {
  72    .name          = TYPE_IMX7_SNVS,
  73    .parent        = TYPE_SYS_BUS_DEVICE,
  74    .instance_size = sizeof(IMX7SNVSState),
  75    .instance_init = imx7_snvs_init,
  76    .class_init    = imx7_snvs_class_init,
  77};
  78
  79static void imx7_snvs_register_type(void)
  80{
  81    type_register_static(&imx7_snvs_info);
  82}
  83type_init(imx7_snvs_register_type)
  84