qemu-e2k/hw/misc/bcm2835_rng.c
Bernhard Beschow 5e78c98b7c Mark remaining global TypeInfo instances as const
More than 1k of TypeInfo instances are already marked as const. Mark the
remaining ones, too.

This commit was created with:
  git grep -z -l 'static TypeInfo' -- '*.c' | \
  xargs -0 sed -i 's/static TypeInfo/static const TypeInfo/'

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Message-id: 20220117145805.173070-2-shentey@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-02-21 13:30:20 +00:00

148 lines
3.9 KiB
C

/*
* BCM2835 Random Number Generator emulation
*
* Copyright (C) 2017 Marcin Chojnacki <marcinch7@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.
*/
#include "qemu/osdep.h"
#include "qemu/log.h"
#include "qemu/guest-random.h"
#include "qemu/module.h"
#include "hw/misc/bcm2835_rng.h"
#include "migration/vmstate.h"
static uint32_t get_random_bytes(void)
{
uint32_t res;
/*
* On failure we don't want to return the guest a non-random
* value in case they're really using it for cryptographic
* purposes, so the best we can do is die here.
* This shouldn't happen unless something's broken.
* In theory we could implement this device's full FIFO
* and interrupt semantics and then just stop filling the
* FIFO. That's a lot of work, though, so we assume any
* errors are systematic problems and trust that if we didn't
* fail as the guest inited then we won't fail later on
* mid-run.
*/
qemu_guest_getrandom_nofail(&res, sizeof(res));
return res;
}
static uint64_t bcm2835_rng_read(void *opaque, hwaddr offset,
unsigned size)
{
BCM2835RngState *s = (BCM2835RngState *)opaque;
uint32_t res = 0;
assert(size == 4);
switch (offset) {
case 0x0: /* rng_ctrl */
res = s->rng_ctrl;
break;
case 0x4: /* rng_status */
res = s->rng_status | (1 << 24);
break;
case 0x8: /* rng_data */
res = get_random_bytes();
break;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"bcm2835_rng_read: Bad offset %x\n",
(int)offset);
res = 0;
break;
}
return res;
}
static void bcm2835_rng_write(void *opaque, hwaddr offset,
uint64_t value, unsigned size)
{
BCM2835RngState *s = (BCM2835RngState *)opaque;
assert(size == 4);
switch (offset) {
case 0x0: /* rng_ctrl */
s->rng_ctrl = value;
break;
case 0x4: /* rng_status */
/* we shouldn't let the guest write to bits [31..20] */
s->rng_status &= ~0xFFFFF; /* clear 20 lower bits */
s->rng_status |= value & 0xFFFFF; /* set them to new value */
break;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"bcm2835_rng_write: Bad offset %x\n",
(int)offset);
break;
}
}
static const MemoryRegionOps bcm2835_rng_ops = {
.read = bcm2835_rng_read,
.write = bcm2835_rng_write,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static const VMStateDescription vmstate_bcm2835_rng = {
.name = TYPE_BCM2835_RNG,
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32(rng_ctrl, BCM2835RngState),
VMSTATE_UINT32(rng_status, BCM2835RngState),
VMSTATE_END_OF_LIST()
}
};
static void bcm2835_rng_init(Object *obj)
{
BCM2835RngState *s = BCM2835_RNG(obj);
memory_region_init_io(&s->iomem, obj, &bcm2835_rng_ops, s,
TYPE_BCM2835_RNG, 0x10);
sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
}
static void bcm2835_rng_reset(DeviceState *dev)
{
BCM2835RngState *s = BCM2835_RNG(dev);
s->rng_ctrl = 0;
s->rng_status = 0;
}
static void bcm2835_rng_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->reset = bcm2835_rng_reset;
dc->vmsd = &vmstate_bcm2835_rng;
}
static const TypeInfo bcm2835_rng_info = {
.name = TYPE_BCM2835_RNG,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(BCM2835RngState),
.class_init = bcm2835_rng_class_init,
.instance_init = bcm2835_rng_init,
};
static void bcm2835_rng_register_types(void)
{
type_register_static(&bcm2835_rng_info);
}
type_init(bcm2835_rng_register_types)