qemu-patch-raspberry4/hw/misc/vmport.c
Markus Armbruster efec3dd631 qdev: Replace no_user by cannot_instantiate_with_device_add_yet
In an ideal world, machines can be built by wiring devices together
with configuration, not code.  Unfortunately, that's not the world we
live in right now.  We still have quite a few devices that need to be
wired up by code.  If you try to device_add such a device, it'll fail
in sometimes mysterious ways.  If you're lucky, you get an
unmysterious immediate crash.

To protect users from such badness, DeviceClass member no_user used to
make device models unavailable with -device / device_add, but that
regressed in commit 18b6dad.  The device model is still omitted from
help, but is available anyway.

Attempts to fix the regression have been rejected with the argument
that the purpose of no_user isn't clear, and it's prone to misuse.

This commit clarifies no_user's purpose.  Anthony suggested to rename
it cannot_instantiate_with_device_add_yet_due_to_internal_bugs, which
I shorten somewhat to keep checkpatch happy.  While there, make it
bool.

Every use of cannot_instantiate_with_device_add_yet gets a FIXME
comment asking for rationale.  The next few commits will clean them
all up, either by providing a rationale, or by getting rid of the use.

With that done, the regression fix is hopefully acceptable.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-12-23 00:27:22 +01:00

181 lines
5 KiB
C

/*
* QEMU VMPort emulation
*
* Copyright (C) 2007 Hervé Poussineau
*
* 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 "hw/hw.h"
#include "hw/isa/isa.h"
#include "hw/i386/pc.h"
#include "sysemu/kvm.h"
#include "hw/qdev.h"
//#define VMPORT_DEBUG
#define VMPORT_CMD_GETVERSION 0x0a
#define VMPORT_CMD_GETRAMSIZE 0x14
#define VMPORT_ENTRIES 0x2c
#define VMPORT_MAGIC 0x564D5868
#define TYPE_VMPORT "vmport"
#define VMPORT(obj) OBJECT_CHECK(VMPortState, (obj), TYPE_VMPORT)
typedef struct VMPortState
{
ISADevice parent_obj;
MemoryRegion io;
VMPortReadFunc *func[VMPORT_ENTRIES];
void *opaque[VMPORT_ENTRIES];
} VMPortState;
static VMPortState *port_state;
void vmport_register(unsigned char command, VMPortReadFunc *func, void *opaque)
{
if (command >= VMPORT_ENTRIES)
return;
port_state->func[command] = func;
port_state->opaque[command] = opaque;
}
static uint64_t vmport_ioport_read(void *opaque, hwaddr addr,
unsigned size)
{
VMPortState *s = opaque;
CPUState *cs = current_cpu;
X86CPU *cpu = X86_CPU(cs);
CPUX86State *env = &cpu->env;
unsigned char command;
uint32_t eax;
cpu_synchronize_state(cs);
eax = env->regs[R_EAX];
if (eax != VMPORT_MAGIC)
return eax;
command = env->regs[R_ECX];
if (command >= VMPORT_ENTRIES)
return eax;
if (!s->func[command])
{
#ifdef VMPORT_DEBUG
fprintf(stderr, "vmport: unknown command %x\n", command);
#endif
return eax;
}
return s->func[command](s->opaque[command], addr);
}
static void vmport_ioport_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
X86CPU *cpu = X86_CPU(current_cpu);
cpu->env.regs[R_EAX] = vmport_ioport_read(opaque, addr, 4);
}
static uint32_t vmport_cmd_get_version(void *opaque, uint32_t addr)
{
X86CPU *cpu = X86_CPU(current_cpu);
cpu->env.regs[R_EBX] = VMPORT_MAGIC;
return 6;
}
static uint32_t vmport_cmd_ram_size(void *opaque, uint32_t addr)
{
X86CPU *cpu = X86_CPU(current_cpu);
cpu->env.regs[R_EBX] = 0x1177;
return ram_size;
}
/* vmmouse helpers */
void vmmouse_get_data(uint32_t *data)
{
X86CPU *cpu = X86_CPU(current_cpu);
CPUX86State *env = &cpu->env;
data[0] = env->regs[R_EAX]; data[1] = env->regs[R_EBX];
data[2] = env->regs[R_ECX]; data[3] = env->regs[R_EDX];
data[4] = env->regs[R_ESI]; data[5] = env->regs[R_EDI];
}
void vmmouse_set_data(const uint32_t *data)
{
X86CPU *cpu = X86_CPU(current_cpu);
CPUX86State *env = &cpu->env;
env->regs[R_EAX] = data[0]; env->regs[R_EBX] = data[1];
env->regs[R_ECX] = data[2]; env->regs[R_EDX] = data[3];
env->regs[R_ESI] = data[4]; env->regs[R_EDI] = data[5];
}
static const MemoryRegionOps vmport_ops = {
.read = vmport_ioport_read,
.write = vmport_ioport_write,
.impl = {
.min_access_size = 4,
.max_access_size = 4,
},
.endianness = DEVICE_LITTLE_ENDIAN,
};
static void vmport_realizefn(DeviceState *dev, Error **errp)
{
ISADevice *isadev = ISA_DEVICE(dev);
VMPortState *s = VMPORT(dev);
memory_region_init_io(&s->io, OBJECT(s), &vmport_ops, s, "vmport", 1);
isa_register_ioport(isadev, &s->io, 0x5658);
port_state = s;
/* Register some generic port commands */
vmport_register(VMPORT_CMD_GETVERSION, vmport_cmd_get_version, NULL);
vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, NULL);
}
static void vmport_class_initfn(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = vmport_realizefn;
dc->cannot_instantiate_with_device_add_yet = true; /* FIXME explain why */
}
static const TypeInfo vmport_info = {
.name = TYPE_VMPORT,
.parent = TYPE_ISA_DEVICE,
.instance_size = sizeof(VMPortState),
.class_init = vmport_class_initfn,
};
static void vmport_register_types(void)
{
type_register_static(&vmport_info);
}
type_init(vmport_register_types)