qemu-e2k/hw/apic_common.c
Jan Kiszka e5ad936b0f kvmvapic: Introduce TPR access optimization for Windows guests
This enables acceleration for MMIO-based TPR registers accesses of
32-bit Windows guest systems. It is mostly useful with KVM enabled,
either on older Intel CPUs (without flexpriority feature, can also be
manually disabled for testing) or any current AMD processor.

The approach introduced here is derived from the original version of
qemu-kvm. It was refactored, documented, and extended by support for
user space APIC emulation, both with and without KVM acceleration. The
VMState format was kept compatible, so was the ABI to the option ROM
that implements the guest-side para-virtualized driver service. This
enables seamless migration from qemu-kvm to upstream or, one day,
between KVM and TCG mode.

The basic concept goes like this:
 - VAPIC PV interface consisting of I/O port 0x7e and (for KVM in-kernel
   irqchip) a vmcall hypercall is registered
 - VAPIC option ROM is loaded into guest
 - option ROM activates TPR MMIO access reporting via port 0x7e
 - TPR accesses are trapped and patched in the guest to call into option
   ROM instead, VAPIC support is enabled
 - option ROM TPR helpers track state in memory and invoke hypercall to
   poll for pending IRQs if required

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-02-18 12:15:59 +02:00

392 lines
10 KiB
C

/*
* APIC support - common bits of emulated and KVM kernel model
*
* Copyright (c) 2004-2005 Fabrice Bellard
* Copyright (c) 2011 Jan Kiszka, Siemens AG
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>
*/
#include "apic.h"
#include "apic_internal.h"
#include "trace.h"
#include "kvm.h"
static int apic_irq_delivered;
bool apic_report_tpr_access;
void cpu_set_apic_base(DeviceState *d, uint64_t val)
{
trace_cpu_set_apic_base(val);
if (d) {
APICCommonState *s = APIC_COMMON(d);
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
info->set_base(s, val);
}
}
uint64_t cpu_get_apic_base(DeviceState *d)
{
if (d) {
APICCommonState *s = APIC_COMMON(d);
trace_cpu_get_apic_base((uint64_t)s->apicbase);
return s->apicbase;
} else {
trace_cpu_get_apic_base(0);
return 0;
}
}
void cpu_set_apic_tpr(DeviceState *d, uint8_t val)
{
APICCommonState *s;
APICCommonClass *info;
if (!d) {
return;
}
s = APIC_COMMON(d);
info = APIC_COMMON_GET_CLASS(s);
info->set_tpr(s, val);
}
uint8_t cpu_get_apic_tpr(DeviceState *d)
{
APICCommonState *s;
APICCommonClass *info;
if (!d) {
return 0;
}
s = APIC_COMMON(d);
info = APIC_COMMON_GET_CLASS(s);
return info->get_tpr(s);
}
void apic_enable_tpr_access_reporting(DeviceState *d, bool enable)
{
APICCommonState *s = DO_UPCAST(APICCommonState, busdev.qdev, d);
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
apic_report_tpr_access = enable;
if (info->enable_tpr_reporting) {
info->enable_tpr_reporting(s, enable);
}
}
void apic_enable_vapic(DeviceState *d, target_phys_addr_t paddr)
{
APICCommonState *s = DO_UPCAST(APICCommonState, busdev.qdev, d);
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
s->vapic_paddr = paddr;
info->vapic_base_update(s);
}
void apic_handle_tpr_access_report(DeviceState *d, target_ulong ip,
TPRAccess access)
{
APICCommonState *s = DO_UPCAST(APICCommonState, busdev.qdev, d);
vapic_report_tpr_access(s->vapic, s->cpu_env, ip, access);
}
void apic_report_irq_delivered(int delivered)
{
apic_irq_delivered += delivered;
trace_apic_report_irq_delivered(apic_irq_delivered);
}
void apic_reset_irq_delivered(void)
{
trace_apic_reset_irq_delivered(apic_irq_delivered);
apic_irq_delivered = 0;
}
int apic_get_irq_delivered(void)
{
trace_apic_get_irq_delivered(apic_irq_delivered);
return apic_irq_delivered;
}
void apic_deliver_nmi(DeviceState *d)
{
APICCommonState *s = APIC_COMMON(d);
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
info->external_nmi(s);
}
bool apic_next_timer(APICCommonState *s, int64_t current_time)
{
int64_t d;
/* We need to store the timer state separately to support APIC
* implementations that maintain a non-QEMU timer, e.g. inside the
* host kernel. This open-coded state allows us to migrate between
* both models. */
s->timer_expiry = -1;
if (s->lvt[APIC_LVT_TIMER] & APIC_LVT_MASKED) {
return false;
}
d = (current_time - s->initial_count_load_time) >> s->count_shift;
if (s->lvt[APIC_LVT_TIMER] & APIC_LVT_TIMER_PERIODIC) {
if (!s->initial_count) {
return false;
}
d = ((d / ((uint64_t)s->initial_count + 1)) + 1) *
((uint64_t)s->initial_count + 1);
} else {
if (d >= s->initial_count) {
return false;
}
d = (uint64_t)s->initial_count + 1;
}
s->next_time = s->initial_count_load_time + (d << s->count_shift);
s->timer_expiry = s->next_time;
return true;
}
void apic_init_reset(DeviceState *d)
{
APICCommonState *s = DO_UPCAST(APICCommonState, busdev.qdev, d);
int i;
if (!s) {
return;
}
s->tpr = 0;
s->spurious_vec = 0xff;
s->log_dest = 0;
s->dest_mode = 0xf;
memset(s->isr, 0, sizeof(s->isr));
memset(s->tmr, 0, sizeof(s->tmr));
memset(s->irr, 0, sizeof(s->irr));
for (i = 0; i < APIC_LVT_NB; i++) {
s->lvt[i] = APIC_LVT_MASKED;
}
s->esr = 0;
memset(s->icr, 0, sizeof(s->icr));
s->divide_conf = 0;
s->count_shift = 0;
s->initial_count = 0;
s->initial_count_load_time = 0;
s->next_time = 0;
s->wait_for_sipi = 1;
if (s->timer) {
qemu_del_timer(s->timer);
}
s->timer_expiry = -1;
}
static void apic_reset_common(DeviceState *d)
{
APICCommonState *s = DO_UPCAST(APICCommonState, busdev.qdev, d);
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
bool bsp;
bsp = cpu_is_bsp(s->cpu_env);
s->apicbase = 0xfee00000 |
(bsp ? MSR_IA32_APICBASE_BSP : 0) | MSR_IA32_APICBASE_ENABLE;
s->vapic_paddr = 0;
info->vapic_base_update(s);
apic_init_reset(d);
if (bsp) {
/*
* LINT0 delivery mode on CPU #0 is set to ExtInt at initialization
* time typically by BIOS, so PIC interrupt can be delivered to the
* processor when local APIC is enabled.
*/
s->lvt[APIC_LVT_LINT0] = 0x700;
}
}
/* This function is only used for old state version 1 and 2 */
static int apic_load_old(QEMUFile *f, void *opaque, int version_id)
{
APICCommonState *s = opaque;
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
int i;
if (version_id > 2) {
return -EINVAL;
}
/* XXX: what if the base changes? (registered memory regions) */
qemu_get_be32s(f, &s->apicbase);
qemu_get_8s(f, &s->id);
qemu_get_8s(f, &s->arb_id);
qemu_get_8s(f, &s->tpr);
qemu_get_be32s(f, &s->spurious_vec);
qemu_get_8s(f, &s->log_dest);
qemu_get_8s(f, &s->dest_mode);
for (i = 0; i < 8; i++) {
qemu_get_be32s(f, &s->isr[i]);
qemu_get_be32s(f, &s->tmr[i]);
qemu_get_be32s(f, &s->irr[i]);
}
for (i = 0; i < APIC_LVT_NB; i++) {
qemu_get_be32s(f, &s->lvt[i]);
}
qemu_get_be32s(f, &s->esr);
qemu_get_be32s(f, &s->icr[0]);
qemu_get_be32s(f, &s->icr[1]);
qemu_get_be32s(f, &s->divide_conf);
s->count_shift = qemu_get_be32(f);
qemu_get_be32s(f, &s->initial_count);
s->initial_count_load_time = qemu_get_be64(f);
s->next_time = qemu_get_be64(f);
if (version_id >= 2) {
s->timer_expiry = qemu_get_be64(f);
}
if (info->post_load) {
info->post_load(s);
}
return 0;
}
static int apic_init_common(SysBusDevice *dev)
{
APICCommonState *s = APIC_COMMON(dev);
APICCommonClass *info;
static DeviceState *vapic;
static int apic_no;
if (apic_no >= MAX_APICS) {
return -1;
}
s->idx = apic_no++;
info = APIC_COMMON_GET_CLASS(s);
info->init(s);
sysbus_init_mmio(dev, &s->io_memory);
if (!vapic && s->vapic_control & VAPIC_ENABLE_MASK) {
vapic = sysbus_create_simple("kvmvapic", -1, NULL);
}
s->vapic = vapic;
if (apic_report_tpr_access && info->enable_tpr_reporting) {
info->enable_tpr_reporting(s, true);
}
return 0;
}
static void apic_dispatch_pre_save(void *opaque)
{
APICCommonState *s = APIC_COMMON(opaque);
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
if (info->pre_save) {
info->pre_save(s);
}
}
static int apic_dispatch_post_load(void *opaque, int version_id)
{
APICCommonState *s = APIC_COMMON(opaque);
APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
if (info->post_load) {
info->post_load(s);
}
return 0;
}
static const VMStateDescription vmstate_apic_common = {
.name = "apic",
.version_id = 3,
.minimum_version_id = 3,
.minimum_version_id_old = 1,
.load_state_old = apic_load_old,
.pre_save = apic_dispatch_pre_save,
.post_load = apic_dispatch_post_load,
.fields = (VMStateField[]) {
VMSTATE_UINT32(apicbase, APICCommonState),
VMSTATE_UINT8(id, APICCommonState),
VMSTATE_UINT8(arb_id, APICCommonState),
VMSTATE_UINT8(tpr, APICCommonState),
VMSTATE_UINT32(spurious_vec, APICCommonState),
VMSTATE_UINT8(log_dest, APICCommonState),
VMSTATE_UINT8(dest_mode, APICCommonState),
VMSTATE_UINT32_ARRAY(isr, APICCommonState, 8),
VMSTATE_UINT32_ARRAY(tmr, APICCommonState, 8),
VMSTATE_UINT32_ARRAY(irr, APICCommonState, 8),
VMSTATE_UINT32_ARRAY(lvt, APICCommonState, APIC_LVT_NB),
VMSTATE_UINT32(esr, APICCommonState),
VMSTATE_UINT32_ARRAY(icr, APICCommonState, 2),
VMSTATE_UINT32(divide_conf, APICCommonState),
VMSTATE_INT32(count_shift, APICCommonState),
VMSTATE_UINT32(initial_count, APICCommonState),
VMSTATE_INT64(initial_count_load_time, APICCommonState),
VMSTATE_INT64(next_time, APICCommonState),
VMSTATE_INT64(timer_expiry,
APICCommonState), /* open-coded timer state */
VMSTATE_END_OF_LIST()
}
};
static Property apic_properties_common[] = {
DEFINE_PROP_UINT8("id", APICCommonState, id, -1),
DEFINE_PROP_PTR("cpu_env", APICCommonState, cpu_env),
DEFINE_PROP_BIT("vapic", APICCommonState, vapic_control, VAPIC_ENABLE_BIT,
true),
DEFINE_PROP_END_OF_LIST(),
};
static void apic_common_class_init(ObjectClass *klass, void *data)
{
SysBusDeviceClass *sc = SYS_BUS_DEVICE_CLASS(klass);
DeviceClass *dc = DEVICE_CLASS(klass);
dc->vmsd = &vmstate_apic_common;
dc->reset = apic_reset_common;
dc->no_user = 1;
dc->props = apic_properties_common;
sc->init = apic_init_common;
}
static TypeInfo apic_common_type = {
.name = TYPE_APIC_COMMON,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(APICCommonState),
.class_size = sizeof(APICCommonClass),
.class_init = apic_common_class_init,
.abstract = true,
};
static void register_types(void)
{
type_register_static(&apic_common_type);
}
type_init(register_types)