qemu/hw/block/pc_sysfw.c
Paolo Bonzini 9e1c2ec8fd Revert "pc: Kill the "use flash device for BIOS unless KVM" misfeature"
This reverts commit 9953f8822c.
While Markus's analysis is entirely correct, there are 1.6 patches
that fix the bug for real and without requiring machine type hacks.
Let's think of the children who will have to read this code, and
avoid a complicated mess of semantics that differ between <1.5,
1.5, and >1.5.

Conflicts:
	hw/i386/pc_piix.c
	hw/i386/pc_q35.c
	include/hw/i386/pc.h

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Anthony Liguori <aliguori@us.ibm.com>
Message-id: 1368189483-7915-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-05-13 09:52:43 -05:00

290 lines
8.4 KiB
C

/*
* QEMU PC System Firmware
*
* Copyright (c) 2003-2004 Fabrice Bellard
* Copyright (c) 2011-2012 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "sysemu/blockdev.h"
#include "qemu/error-report.h"
#include "hw/sysbus.h"
#include "hw/hw.h"
#include "hw/i386/pc.h"
#include "hw/boards.h"
#include "hw/loader.h"
#include "sysemu/sysemu.h"
#include "hw/block/flash.h"
#include "sysemu/kvm.h"
#define BIOS_FILENAME "bios.bin"
typedef struct PcSysFwDevice {
SysBusDevice busdev;
uint8_t rom_only;
} PcSysFwDevice;
static void pc_isa_bios_init(MemoryRegion *rom_memory,
MemoryRegion *flash_mem,
int ram_size)
{
int isa_bios_size;
MemoryRegion *isa_bios;
uint64_t flash_size;
void *flash_ptr, *isa_bios_ptr;
flash_size = memory_region_size(flash_mem);
/* map the last 128KB of the BIOS in ISA space */
isa_bios_size = flash_size;
if (isa_bios_size > (128 * 1024)) {
isa_bios_size = 128 * 1024;
}
isa_bios = g_malloc(sizeof(*isa_bios));
memory_region_init_ram(isa_bios, "isa-bios", isa_bios_size);
vmstate_register_ram_global(isa_bios);
memory_region_add_subregion_overlap(rom_memory,
0x100000 - isa_bios_size,
isa_bios,
1);
/* copy ISA rom image from top of flash memory */
flash_ptr = memory_region_get_ram_ptr(flash_mem);
isa_bios_ptr = memory_region_get_ram_ptr(isa_bios);
memcpy(isa_bios_ptr,
((uint8_t*)flash_ptr) + (flash_size - isa_bios_size),
isa_bios_size);
memory_region_set_readonly(isa_bios, true);
}
static void pc_fw_add_pflash_drv(void)
{
QemuOpts *opts;
QEMUMachine *machine;
char *filename;
if (bios_name == NULL) {
bios_name = BIOS_FILENAME;
}
filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
if (!filename) {
error_report("Can't open BIOS image %s", bios_name);
exit(1);
}
opts = drive_add(IF_PFLASH, -1, filename, "readonly=on");
g_free(filename);
if (opts == NULL) {
return;
}
machine = find_default_machine();
if (machine == NULL) {
return;
}
if (!drive_init(opts, machine->block_default_type)) {
qemu_opts_del(opts);
}
}
static void pc_system_flash_init(MemoryRegion *rom_memory,
DriveInfo *pflash_drv)
{
BlockDriverState *bdrv;
int64_t size;
hwaddr phys_addr;
int sector_bits, sector_size;
pflash_t *system_flash;
MemoryRegion *flash_mem;
bdrv = pflash_drv->bdrv;
size = bdrv_getlength(pflash_drv->bdrv);
sector_bits = 12;
sector_size = 1 << sector_bits;
if ((size % sector_size) != 0) {
fprintf(stderr,
"qemu: PC system firmware (pflash) must be a multiple of 0x%x\n",
sector_size);
exit(1);
}
phys_addr = 0x100000000ULL - size;
system_flash = pflash_cfi01_register(phys_addr, NULL, "system.flash", size,
bdrv, sector_size, size >> sector_bits,
1, 0x0000, 0x0000, 0x0000, 0x0000, 0);
flash_mem = pflash_cfi01_get_memory(system_flash);
pc_isa_bios_init(rom_memory, flash_mem, size);
}
static void old_pc_system_rom_init(MemoryRegion *rom_memory)
{
char *filename;
MemoryRegion *bios, *isa_bios;
int bios_size, isa_bios_size;
int ret;
/* BIOS load */
if (bios_name == NULL) {
bios_name = BIOS_FILENAME;
}
filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
if (filename) {
bios_size = get_image_size(filename);
} else {
bios_size = -1;
}
if (bios_size <= 0 ||
(bios_size % 65536) != 0) {
goto bios_error;
}
bios = g_malloc(sizeof(*bios));
memory_region_init_ram(bios, "pc.bios", bios_size);
vmstate_register_ram_global(bios);
memory_region_set_readonly(bios, true);
ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
if (ret != 0) {
bios_error:
fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
exit(1);
}
if (filename) {
g_free(filename);
}
/* map the last 128KB of the BIOS in ISA space */
isa_bios_size = bios_size;
if (isa_bios_size > (128 * 1024)) {
isa_bios_size = 128 * 1024;
}
isa_bios = g_malloc(sizeof(*isa_bios));
memory_region_init_alias(isa_bios, "isa-bios", bios,
bios_size - isa_bios_size, isa_bios_size);
memory_region_add_subregion_overlap(rom_memory,
0x100000 - isa_bios_size,
isa_bios,
1);
memory_region_set_readonly(isa_bios, true);
/* map all the bios at the top of memory */
memory_region_add_subregion(rom_memory,
(uint32_t)(-bios_size),
bios);
}
/*
* Bug-compatible flash vs. ROM selection enabled?
* A few older machines enable this.
*/
bool pc_sysfw_flash_vs_rom_bug_compatible;
void pc_system_firmware_init(MemoryRegion *rom_memory)
{
DriveInfo *pflash_drv;
PcSysFwDevice *sysfw_dev;
/*
* TODO This device exists only so that users can switch between
* use of flash and ROM for the BIOS. The ability to switch was
* created because flash doesn't work with KVM. Once it does, we
* should drop this device.
*/
sysfw_dev = (PcSysFwDevice*) qdev_create(NULL, "pc-sysfw");
qdev_init_nofail(DEVICE(sysfw_dev));
if (sysfw_dev->rom_only) {
old_pc_system_rom_init(rom_memory);
return;
}
pflash_drv = drive_get(IF_PFLASH, 0, 0);
/* Currently KVM cannot execute from device memory.
Use old rom based firmware initialization for KVM. */
/*
* This is a Bad Idea, because it makes enabling/disabling KVM
* guest-visible. Let's fix it for real in QEMU 1.6.
*/
if (kvm_enabled()) {
if (pflash_drv != NULL) {
fprintf(stderr, "qemu: pflash cannot be used with kvm enabled\n");
exit(1);
} else {
sysfw_dev->rom_only = 1;
old_pc_system_rom_init(rom_memory);
return;
}
}
/* If a pflash drive is not found, then create one using
the bios filename. */
if (pflash_drv == NULL) {
pc_fw_add_pflash_drv();
pflash_drv = drive_get(IF_PFLASH, 0, 0);
}
if (pflash_drv != NULL) {
pc_system_flash_init(rom_memory, pflash_drv);
} else {
fprintf(stderr, "qemu: PC system firmware (pflash) not available\n");
exit(1);
}
}
static Property pcsysfw_properties[] = {
DEFINE_PROP_UINT8("rom_only", PcSysFwDevice, rom_only, 0),
DEFINE_PROP_END_OF_LIST(),
};
static int pcsysfw_init(DeviceState *dev)
{
return 0;
}
static void pcsysfw_class_init (ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS (klass);
dc->desc = "PC System Firmware";
dc->init = pcsysfw_init;
dc->props = pcsysfw_properties;
}
static const TypeInfo pcsysfw_info = {
.name = "pc-sysfw",
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof (PcSysFwDevice),
.class_init = pcsysfw_class_init,
};
static void pcsysfw_register (void)
{
type_register_static (&pcsysfw_info);
}
type_init (pcsysfw_register);