qemu/hw/empty_slot.c
Stefan Weil 1a00282a73 sparc: Fix assertion caused by empty memory slot with 0 byte
If the memory size given on the command line is equal to the
maximum size of memory defined by the hardware, there is no
"empty slot" after physical memory.

The following command

		qemu-system-sparc -m 256

raised an assertion:
exec.c:2614: cpu_register_physical_memory_offset: Assertion `size' failed

This can be fixed either at the caller side (don't call empty_slot_init)
or in empty_slot_init (do nothing) when size == 0. The second solution
was choosen here because it is more robust.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
2011-04-15 18:16:34 +00:00

96 lines
2.3 KiB
C

/*
* QEMU Empty Slot
*
* The empty_slot device emulates known to a bus but not connected devices.
*
* Copyright (c) 2010 Artyom Tarasenko
*
* This code is licensed under the GNU GPL v2 or (at your option) any later
* version.
*/
#include "hw.h"
#include "sysbus.h"
#include "empty_slot.h"
//#define DEBUG_EMPTY_SLOT
#ifdef DEBUG_EMPTY_SLOT
#define DPRINTF(fmt, ...) \
do { printf("empty_slot: " fmt , ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) do {} while (0)
#endif
typedef struct EmptySlot {
SysBusDevice busdev;
uint64_t size;
} EmptySlot;
static uint32_t empty_slot_readl(void *opaque, target_phys_addr_t addr)
{
DPRINTF("read from " TARGET_FMT_plx "\n", addr);
return 0;
}
static void empty_slot_writel(void *opaque, target_phys_addr_t addr,
uint32_t val)
{
DPRINTF("write 0x%x to " TARGET_FMT_plx "\n", val, addr);
}
CPUReadMemoryFunc * const empty_slot_read[3] = {
empty_slot_readl,
empty_slot_readl,
empty_slot_readl,
};
static CPUWriteMemoryFunc * const empty_slot_write[3] = {
empty_slot_writel,
empty_slot_writel,
empty_slot_writel,
};
void empty_slot_init(target_phys_addr_t addr, uint64_t slot_size)
{
if (slot_size > 0) {
/* Only empty slots larger than 0 byte need handling. */
DeviceState *dev;
SysBusDevice *s;
EmptySlot *e;
dev = qdev_create(NULL, "empty_slot");
s = sysbus_from_qdev(dev);
e = FROM_SYSBUS(EmptySlot, s);
e->size = slot_size;
qdev_init_nofail(dev);
sysbus_mmio_map(s, 0, addr);
}
}
static int empty_slot_init1(SysBusDevice *dev)
{
EmptySlot *s = FROM_SYSBUS(EmptySlot, dev);
ram_addr_t empty_slot_offset;
empty_slot_offset = cpu_register_io_memory(empty_slot_read,
empty_slot_write, s,
DEVICE_NATIVE_ENDIAN);
sysbus_init_mmio(dev, s->size, empty_slot_offset | IO_MEM_RAM);
return 0;
}
static SysBusDeviceInfo empty_slot_info = {
.init = empty_slot_init1,
.qdev.name = "empty_slot",
.qdev.size = sizeof(EmptySlot),
};
static void empty_slot_register_devices(void)
{
sysbus_register_withprop(&empty_slot_info);
}
device_init(empty_slot_register_devices);