qemu/include/hw/i386/pc.h
Markus Armbruster 9953f8822c pc: Kill the "use flash device for BIOS unless KVM" misfeature
Use of a flash memory device for the BIOS was added in series "[PATCH
v10 0/8] PC system flash support", commit 4732dca..1b89faf, v1.1.

Flash vs. ROM is a guest-visible difference.  Thus, flash use had to
be suppressed for machine types pc-1.0 and older.  This was
accomplished by adding a dummy device "pc-sysfw" with property
"rom_only":

* Non-zero rom_only means "use ROM".  Default for pc-1.0 and older.
* Zero rom_only means "maybe use flash".  Default for newer machines.

Not only is the dummy device ugly, it was also retroactively added to
the older machine types!  Fortunately, it's not guest-visible (thus no
immediate guest ABI breakage), and has no vmstate (thus no immediate
migration breakage).  Breakage occurs only if the user unwisely
enables flash by setting rom_only to zero.  Patch review FAIL #1.

Why "maybe use flash"?  Flash didn't (and still doesn't) work with
KVM.  Therefore, rom_only=0 really means "use flash, except when KVM
is enabled, use ROM".  This is a Bad Idea, because it makes enabling/
disabling KVM guest-visible.  Patch review FAIL #2.

Aside: it also precludes migrating between KVM on and off, but that's
not possible for other reasons anyway.

Fix as follows:

1. Change the meaning of rom_only=0 to mean "use flash, no ifs, buts,
or maybes" for pc-i440fx-1.5 and pc-q35-1.5.  Don't change anything
for older machines (to remain bug-compatible).

2. Change the default value from 0 to 1 for these machines.
Necessary, because 0 doesn't work with KVM.  Once it does, we can flip
the default back to 0.

3. Don't revert the retroactive addition of device "pc-sysfw" to older
machine types.  Seems not worth the trouble.

4. Add a TODO comment asking for device "pc-sysfw" to be dropped once
flash works with KVM.

Net effect is that you get a BIOS ROM again even when KVM is disabled,
just like for machines predating the introduction of flash.

To get flash instead, use "--global pc-sysfw.rom_only=0".

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1365780303-26398-4-git-send-email-armbru@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-24 13:23:51 -05:00

244 lines
7.3 KiB
C

#ifndef HW_PC_H
#define HW_PC_H
#include "qemu-common.h"
#include "exec/memory.h"
#include "exec/ioport.h"
#include "hw/isa/isa.h"
#include "hw/block/fdc.h"
#include "net/net.h"
#include "exec/memory.h"
#include "hw/i386/ioapic.h"
/* PC-style peripherals (also used by other machines). */
/* parallel.c */
static inline bool parallel_init(ISABus *bus, int index, CharDriverState *chr)
{
ISADevice *dev;
dev = isa_try_create(bus, "isa-parallel");
if (!dev) {
return false;
}
qdev_prop_set_uint32(&dev->qdev, "index", index);
qdev_prop_set_chr(&dev->qdev, "chardev", chr);
if (qdev_init(&dev->qdev) < 0) {
return false;
}
return true;
}
bool parallel_mm_init(MemoryRegion *address_space,
hwaddr base, int it_shift, qemu_irq irq,
CharDriverState *chr);
/* i8259.c */
extern DeviceState *isa_pic;
qemu_irq *i8259_init(ISABus *bus, qemu_irq parent_irq);
qemu_irq *kvm_i8259_init(ISABus *bus);
int pic_read_irq(DeviceState *d);
int pic_get_output(DeviceState *d);
void pic_info(Monitor *mon, const QDict *qdict);
void irq_info(Monitor *mon, const QDict *qdict);
/* Global System Interrupts */
#define GSI_NUM_PINS IOAPIC_NUM_PINS
typedef struct GSIState {
qemu_irq i8259_irq[ISA_NUM_IRQS];
qemu_irq ioapic_irq[IOAPIC_NUM_PINS];
} GSIState;
void gsi_handler(void *opaque, int n, int level);
/* vmport.c */
static inline void vmport_init(ISABus *bus)
{
isa_create_simple(bus, "vmport");
}
void vmport_register(unsigned char command, IOPortReadFunc *func, void *opaque);
void vmmouse_get_data(uint32_t *data);
void vmmouse_set_data(const uint32_t *data);
/* pckbd.c */
void i8042_init(qemu_irq kbd_irq, qemu_irq mouse_irq, uint32_t io_base);
void i8042_mm_init(qemu_irq kbd_irq, qemu_irq mouse_irq,
MemoryRegion *region, ram_addr_t size,
hwaddr mask);
void i8042_isa_mouse_fake_event(void *opaque);
void i8042_setup_a20_line(ISADevice *dev, qemu_irq *a20_out);
/* pc.c */
extern int fd_bootchk;
void pc_register_ferr_irq(qemu_irq irq);
void pc_acpi_smi_interrupt(void *opaque, int irq, int level);
void pc_cpus_init(const char *cpu_model);
void pc_acpi_init(const char *default_dsdt);
void *pc_memory_init(MemoryRegion *system_memory,
const char *kernel_filename,
const char *kernel_cmdline,
const char *initrd_filename,
ram_addr_t below_4g_mem_size,
ram_addr_t above_4g_mem_size,
MemoryRegion *rom_memory,
MemoryRegion **ram_memory);
qemu_irq *pc_allocate_cpu_irq(void);
DeviceState *pc_vga_init(ISABus *isa_bus, PCIBus *pci_bus);
void pc_basic_device_init(ISABus *isa_bus, qemu_irq *gsi,
ISADevice **rtc_state,
ISADevice **floppy,
bool no_vmport);
void pc_init_ne2k_isa(ISABus *bus, NICInfo *nd);
void pc_cmos_init(ram_addr_t ram_size, ram_addr_t above_4g_mem_size,
const char *boot_device,
ISADevice *floppy, BusState *ide0, BusState *ide1,
ISADevice *s);
void pc_nic_init(ISABus *isa_bus, PCIBus *pci_bus);
void pc_pci_device_init(PCIBus *pci_bus);
typedef void (*cpu_set_smm_t)(int smm, void *arg);
void cpu_smm_register(cpu_set_smm_t callback, void *arg);
void ioapic_init_gsi(GSIState *gsi_state, const char *parent_name);
/* acpi_piix.c */
i2c_bus *piix4_pm_init(PCIBus *bus, int devfn, uint32_t smb_io_base,
qemu_irq sci_irq, qemu_irq smi_irq,
int kvm_enabled, void *fw_cfg);
void piix4_smbus_register_device(SMBusDevice *dev, uint8_t addr);
/* hpet.c */
extern int no_hpet;
/* piix_pci.c */
struct PCII440FXState;
typedef struct PCII440FXState PCII440FXState;
PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix_devfn,
ISABus **isa_bus, qemu_irq *pic,
MemoryRegion *address_space_mem,
MemoryRegion *address_space_io,
ram_addr_t ram_size,
hwaddr pci_hole_start,
hwaddr pci_hole_size,
hwaddr pci_hole64_start,
hwaddr pci_hole64_size,
MemoryRegion *pci_memory,
MemoryRegion *ram_memory);
/* piix4.c */
extern PCIDevice *piix4_dev;
int piix4_init(PCIBus *bus, ISABus **isa_bus, int devfn);
/* vga.c */
enum vga_retrace_method {
VGA_RETRACE_DUMB,
VGA_RETRACE_PRECISE
};
extern enum vga_retrace_method vga_retrace_method;
int isa_vga_mm_init(hwaddr vram_base,
hwaddr ctrl_base, int it_shift,
MemoryRegion *address_space);
/* ne2000.c */
static inline bool isa_ne2000_init(ISABus *bus, int base, int irq, NICInfo *nd)
{
ISADevice *dev;
qemu_check_nic_model(nd, "ne2k_isa");
dev = isa_try_create(bus, "ne2k_isa");
if (!dev) {
return false;
}
qdev_prop_set_uint32(&dev->qdev, "iobase", base);
qdev_prop_set_uint32(&dev->qdev, "irq", irq);
qdev_set_nic_properties(&dev->qdev, nd);
qdev_init_nofail(&dev->qdev);
return true;
}
/* pc_sysfw.c */
extern bool pc_sysfw_flash_vs_rom_bug_compatible;
void pc_system_firmware_init(MemoryRegion *rom_memory);
/* e820 types */
#define E820_RAM 1
#define E820_RESERVED 2
#define E820_ACPI 3
#define E820_NVS 4
#define E820_UNUSABLE 5
int e820_add_entry(uint64_t, uint64_t, uint32_t);
#define PC_COMPAT_1_4 \
{\
.driver = "scsi-hd",\
.property = "discard_granularity",\
.value = stringify(0),\
},{\
.driver = "scsi-cd",\
.property = "discard_granularity",\
.value = stringify(0),\
},{\
.driver = "scsi-disk",\
.property = "discard_granularity",\
.value = stringify(0),\
},{\
.driver = "ide-hd",\
.property = "discard_granularity",\
.value = stringify(0),\
},{\
.driver = "ide-cd",\
.property = "discard_granularity",\
.value = stringify(0),\
},{\
.driver = "ide-drive",\
.property = "discard_granularity",\
.value = stringify(0),\
},{\
.driver = "virtio-blk-pci",\
.property = "discard_granularity",\
.value = stringify(0),\
},{\
.driver = "virtio-serial-pci",\
.property = "vectors",\
/* DEV_NVECTORS_UNSPECIFIED as a uint32_t string */\
.value = stringify(0xFFFFFFFF),\
},{\
.driver = "e1000",\
.property = "romfile",\
.value = "pxe-e1000.rom",\
},{\
.driver = "ne2k_pci",\
.property = "romfile",\
.value = "pxe-ne2k_pci.rom",\
},{\
.driver = "pcnet",\
.property = "romfile",\
.value = "pxe-pcnet.rom",\
},{\
.driver = "rtl8139",\
.property = "romfile",\
.value = "pxe-rtl8139.rom",\
},{\
.driver = "virtio-net-pci",\
.property = "romfile",\
.value = "pxe-virtio.rom",\
},{\
.driver = "pc-sysfw",\
.property = "rom_only",\
.value = stringify(0),\
}
#endif