qemu-e2k/hw/misc/imx7_snvs.c

84 lines
2.2 KiB
C

/*
* IMX7 Secure Non-Volatile Storage
*
* Copyright (c) 2018, Impinj, Inc.
*
* Author: Andrey Smirnov <andrew.smirnov@gmail.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
* Bare minimum emulation code needed to support being able to shut
* down linux guest gracefully.
*/
#include "qemu/osdep.h"
#include "hw/misc/imx7_snvs.h"
#include "qemu/module.h"
#include "sysemu/runstate.h"
static uint64_t imx7_snvs_read(void *opaque, hwaddr offset, unsigned size)
{
return 0;
}
static void imx7_snvs_write(void *opaque, hwaddr offset,
uint64_t v, unsigned size)
{
const uint32_t value = v;
const uint32_t mask = SNVS_LPCR_TOP | SNVS_LPCR_DP_EN;
if (offset == SNVS_LPCR && ((value & mask) == mask)) {
qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
}
}
static const struct MemoryRegionOps imx7_snvs_ops = {
.read = imx7_snvs_read,
.write = imx7_snvs_write,
.endianness = DEVICE_NATIVE_ENDIAN,
.impl = {
/*
* Our device would not work correctly if the guest was doing
* unaligned access. This might not be a limitation on the real
* device but in practice there is no reason for a guest to access
* this device unaligned.
*/
.min_access_size = 4,
.max_access_size = 4,
.unaligned = false,
},
};
static void imx7_snvs_init(Object *obj)
{
SysBusDevice *sd = SYS_BUS_DEVICE(obj);
IMX7SNVSState *s = IMX7_SNVS(obj);
memory_region_init_io(&s->mmio, obj, &imx7_snvs_ops, s,
TYPE_IMX7_SNVS, 0x1000);
sysbus_init_mmio(sd, &s->mmio);
}
static void imx7_snvs_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->desc = "i.MX7 Secure Non-Volatile Storage Module";
}
static const TypeInfo imx7_snvs_info = {
.name = TYPE_IMX7_SNVS,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(IMX7SNVSState),
.instance_init = imx7_snvs_init,
.class_init = imx7_snvs_class_init,
};
static void imx7_snvs_register_type(void)
{
type_register_static(&imx7_snvs_info);
}
type_init(imx7_snvs_register_type)