unicorn/qemu/include/hw/boards.h
Peter Maydell 2070ef1c37
boards.h: Define new flag ignore_memory_transaction_failures
Define a new MachineClass field ignore_memory_transaction_failures.
If this is flag is true then the CPU will ignore memory transaction
failures which should cause the CPU to take an exception due to an
access to an unassigned physical address; the transaction will
instead return zero (for a read) or be ignored (for a write). This
should be set only by legacy board models which rely on the old
RAZ/WI behaviour for handling devices that QEMU does not yet model.
New board models should instead use "unimplemented-device" for all
memory ranges where the guest will attempt to probe for a device that
QEMU doesn't implement and a stub device is required.

We need this for ARM boards, where we're about to implement support for
generating external aborts on memory transaction failures. Too many
of our legacy board models rely on the RAZ/WI behaviour and we
would break currently working guests when their "probe for device"
code provoked an external abort rather than a RAZ.

Backports commit ed860129acd3fcd0b1e47884e810212aaca4d21b from qemu
2018-03-04 21:27:15 -05:00

132 lines
4.6 KiB
C

/* Declarations for use by board files for creating devices. */
#ifndef HW_BOARDS_H
#define HW_BOARDS_H
#include "qemu/typedefs.h"
#include "sysemu/accel.h"
#include "hw/qdev.h"
#include "qom/object.h"
#include "qom/cpu.h"
#include "uc_priv.h"
typedef int QEMUMachineInitFunc(struct uc_struct *uc, MachineState *ms);
typedef void QEMUMachineResetFunc(void);
struct QEMUMachine {
const char *family; /* NULL iff @name identifies a standalone machtype */
const char *name;
QEMUMachineInitFunc *init;
QEMUMachineResetFunc *reset;
int max_cpus;
int is_default;
int arch;
int minimum_page_bits;
};
/**
* memory_region_allocate_system_memory - Allocate a board's main memory
* @mr: the #MemoryRegion to be initialized
* @owner: the object that tracks the region's reference count
* @name: name of the memory region
* @ram_size: size of the region in bytes
*
* This function allocates the main memory for a board model, and
* initializes @mr appropriately. It also arranges for the memory
* to be migrated (by calling vmstate_register_ram_global()).
*
* Memory allocated via this function will be backed with the memory
* backend the user provided using "-mem-path" or "-numa node,memdev=..."
* if appropriate; this is typically used to cause host huge pages to be
* used. This function should therefore be called by a board exactly once,
* for the primary or largest RAM area it implements.
*
* For boards where the major RAM is split into two parts in the memory
* map, you can deal with this by calling memory_region_allocate_system_memory()
* once to get a MemoryRegion with enough RAM for both parts, and then
* creating alias MemoryRegions via memory_region_init_alias() which
* alias into different parts of the RAM MemoryRegion and can be mapped
* into the memory map in the appropriate places.
*
* Smaller pieces of memory (display RAM, static RAMs, etc) don't need
* to be backed via the -mem-path memory backend and can simply
* be created via memory_region_init_ram().
*/
void memory_region_allocate_system_memory(MemoryRegion *mr, Object *owner,
const char *name,
uint64_t ram_size);
void qemu_register_machine(struct uc_struct *uc, QEMUMachine *m, const char *type_machine,
void (*init)(struct uc_struct *uc, ObjectClass *oc, void *data));
#define TYPE_MACHINE_SUFFIX "-machine"
#define TYPE_MACHINE "machine"
#undef MACHINE /* BSD defines it and QEMU does not use it */
#define MACHINE(uc, obj) \
OBJECT_CHECK(uc, MachineState, (obj), TYPE_MACHINE)
#define MACHINE_GET_CLASS(uc, obj) \
OBJECT_GET_CLASS(uc, MachineClass, (obj), TYPE_MACHINE)
#define MACHINE_CLASS(uc, klass) \
OBJECT_CLASS_CHECK(uc, MachineClass, (klass), TYPE_MACHINE)
MachineClass *find_default_machine(struct uc_struct *uc, int arch);
/**
* MachineClass:
* @qemu_machine: #QEMUMachine
* @minimum_page_bits:
* If non-zero, the board promises never to create a CPU with a page size
* smaller than this, so QEMU can use a more efficient larger page
* size than the target architecture's minimum. (Attempting to create
* such a CPU will fail.) Note that changing this is a migration
* compatibility break for the machine.
* @ignore_memory_transaction_failures:
* If this is flag is true then the CPU will ignore memory transaction
* failures which should cause the CPU to take an exception due to an
* access to an unassigned physical address; the transaction will instead
* return zero (for a read) or be ignored (for a write). This should be
* set only by legacy board models which rely on the old RAZ/WI behaviour
* for handling devices that QEMU does not yet model. New board models
* should instead use "unimplemented-device" for all memory ranges where
* the guest will attempt to probe for a device that QEMU doesn't
* implement and a stub device is required.
*/
struct MachineClass {
/*< private >*/
ObjectClass parent_class;
/*< public >*/
const char *family; /* NULL iff @name identifies a standalone machtype */
const char *name;
int (*init)(struct uc_struct *uc, MachineState *state);
void (*reset)(void);
int max_cpus;
int is_default;
int arch;
int minimum_page_bits;
bool has_hotpluggable_cpus;
bool ignore_memory_transaction_failures;
};
/**
* MachineState:
*/
struct MachineState {
/*< private >*/
Object parent_obj;
/*< public >*/
ram_addr_t ram_size;
ram_addr_t maxram_size;
const char *cpu_model;
struct uc_struct *uc;
AccelState *accelerator;
};
void machine_register_types(struct uc_struct *uc);
#endif