qemu/hw/piix_pci.c
Isaku Yamahata ab431c283e piix_pci: optimize set irq path
optimize irq routing in piix_pic.c which has been a TODO.
So far piix3 tracks each pirq level and checks whether a given pic pins is
asserted by seeing if each pirq is mapped into the pic pin.
This is independent on irq routing, but data path is on slow path.

Given that irq routing is rarely changed and asserting pic pins is on
data path, the path that asserts pic pins should be optimized and
chainging irq routing should be on slow path.
The new behavior with this patch series is to use bitmap which is addressed
by pirq and pic pins with a given irq routing.
When pirq is asserted, the bitmap is set and see if the pic pins is
asserted by checking the bitmaps.
When irq routing is changed, rebuild the bitmap and re-assert pic pins.

test:
- create VM with 4 e1000 nics in different pci slots
  (i.e. fn=0 for each e1000)
  Thus those e1000's INTA are connected to each PIRQ[A-D].
- run linux as guest and saw each devices triggers interrupt
  by seeing /proc/interrupts. And then confirmed that each PIRQ[A-D]
  surely asserted interrupts.
  Because irq 10 and 11 are shared by 4 e1000's, it only one NIC is activated
  with ifconfig ethN up/down when counting interrupts.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-04-01 15:54:03 +03:00

464 lines
13 KiB
C

/*
* QEMU i440FX/PIIX3 PCI Bridge Emulation
*
* Copyright (c) 2006 Fabrice Bellard
*
* 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.h"
#include "pc.h"
#include "pci.h"
#include "pci_host.h"
#include "isa.h"
#include "sysbus.h"
#include "range.h"
/*
* I440FX chipset data sheet.
* http://download.intel.com/design/chipsets/datashts/29054901.pdf
*/
typedef PCIHostState I440FXState;
#define PIIX_NUM_PIC_IRQS 16 /* i8259 * 2 */
#define PIIX_NUM_PIRQS 4ULL /* PIRQ[A-D] */
#define PIIX_PIRQC 0x60
typedef struct PIIX3State {
PCIDevice dev;
/*
* bitmap to track pic levels.
* The pic level is the logical OR of all the PCI irqs mapped to it
* So one PIC level is tracked by PIIX_NUM_PIRQS bits.
*
* PIRQ is mapped to PIC pins, we track it by
* PIIX_NUM_PIRQS * PIIX_NUM_PIC_IRQS = 64 bits with
* pic_irq * PIIX_NUM_PIRQS + pirq
*/
#if PIIX_NUM_PIC_IRQS * PIIX_NUM_PIRQS > 64
#error "unable to encode pic state in 64bit in pic_levels."
#endif
uint64_t pic_levels;
qemu_irq *pic;
/* This member isn't used. Just for save/load compatibility */
int32_t pci_irq_levels_vmstate[PIIX_NUM_PIRQS];
} PIIX3State;
struct PCII440FXState {
PCIDevice dev;
target_phys_addr_t isa_page_descs[384 / 4];
uint8_t smm_enabled;
PIIX3State *piix3;
};
#define I440FX_PAM 0x59
#define I440FX_PAM_SIZE 7
#define I440FX_SMRAM 0x72
static void piix3_set_irq(void *opaque, int pirq, int level);
/* return the global irq number corresponding to a given device irq
pin. We could also use the bus number to have a more precise
mapping. */
static int pci_slot_get_pirq(PCIDevice *pci_dev, int pci_intx)
{
int slot_addend;
slot_addend = (pci_dev->devfn >> 3) - 1;
return (pci_intx + slot_addend) & 3;
}
static void update_pam(PCII440FXState *d, uint32_t start, uint32_t end, int r)
{
uint32_t addr;
// printf("ISA mapping %08x-0x%08x: %d\n", start, end, r);
switch(r) {
case 3:
/* RAM */
cpu_register_physical_memory(start, end - start,
start);
break;
case 1:
/* ROM (XXX: not quite correct) */
cpu_register_physical_memory(start, end - start,
start | IO_MEM_ROM);
break;
case 2:
case 0:
/* XXX: should distinguish read/write cases */
for(addr = start; addr < end; addr += 4096) {
cpu_register_physical_memory(addr, 4096,
d->isa_page_descs[(addr - 0xa0000) >> 12]);
}
break;
}
}
static void i440fx_update_memory_mappings(PCII440FXState *d)
{
int i, r;
uint32_t smram, addr;
update_pam(d, 0xf0000, 0x100000, (d->dev.config[I440FX_PAM] >> 4) & 3);
for(i = 0; i < 12; i++) {
r = (d->dev.config[(i >> 1) + (I440FX_PAM + 1)] >> ((i & 1) * 4)) & 3;
update_pam(d, 0xc0000 + 0x4000 * i, 0xc0000 + 0x4000 * (i + 1), r);
}
smram = d->dev.config[I440FX_SMRAM];
if ((d->smm_enabled && (smram & 0x08)) || (smram & 0x40)) {
cpu_register_physical_memory(0xa0000, 0x20000, 0xa0000);
} else {
for(addr = 0xa0000; addr < 0xc0000; addr += 4096) {
cpu_register_physical_memory(addr, 4096,
d->isa_page_descs[(addr - 0xa0000) >> 12]);
}
}
}
static void i440fx_set_smm(int val, void *arg)
{
PCII440FXState *d = arg;
val = (val != 0);
if (d->smm_enabled != val) {
d->smm_enabled = val;
i440fx_update_memory_mappings(d);
}
}
/* XXX: suppress when better memory API. We make the assumption that
no device (in particular the VGA) changes the memory mappings in
the 0xa0000-0x100000 range */
void i440fx_init_memory_mappings(PCII440FXState *d)
{
int i;
for(i = 0; i < 96; i++) {
d->isa_page_descs[i] = cpu_get_physical_page_desc(0xa0000 + i * 0x1000);
}
}
static void i440fx_write_config(PCIDevice *dev,
uint32_t address, uint32_t val, int len)
{
PCII440FXState *d = DO_UPCAST(PCII440FXState, dev, dev);
/* XXX: implement SMRAM.D_LOCK */
pci_default_write_config(dev, address, val, len);
if (ranges_overlap(address, len, I440FX_PAM, I440FX_PAM_SIZE) ||
range_covers_byte(address, len, I440FX_SMRAM)) {
i440fx_update_memory_mappings(d);
}
}
static int i440fx_load_old(QEMUFile* f, void *opaque, int version_id)
{
PCII440FXState *d = opaque;
int ret, i;
ret = pci_device_load(&d->dev, f);
if (ret < 0)
return ret;
i440fx_update_memory_mappings(d);
qemu_get_8s(f, &d->smm_enabled);
if (version_id == 2) {
for (i = 0; i < PIIX_NUM_PIRQS; i++) {
qemu_get_be32(f); /* dummy load for compatibility */
}
}
return 0;
}
static int i440fx_post_load(void *opaque, int version_id)
{
PCII440FXState *d = opaque;
i440fx_update_memory_mappings(d);
return 0;
}
static const VMStateDescription vmstate_i440fx = {
.name = "I440FX",
.version_id = 3,
.minimum_version_id = 3,
.minimum_version_id_old = 1,
.load_state_old = i440fx_load_old,
.post_load = i440fx_post_load,
.fields = (VMStateField []) {
VMSTATE_PCI_DEVICE(dev, PCII440FXState),
VMSTATE_UINT8(smm_enabled, PCII440FXState),
VMSTATE_END_OF_LIST()
}
};
static int i440fx_pcihost_initfn(SysBusDevice *dev)
{
I440FXState *s = FROM_SYSBUS(I440FXState, dev);
pci_host_conf_register_ioport(0xcf8, s);
pci_host_data_register_ioport(0xcfc, s);
return 0;
}
static int i440fx_initfn(PCIDevice *dev)
{
PCII440FXState *d = DO_UPCAST(PCII440FXState, dev, dev);
pci_config_set_vendor_id(d->dev.config, PCI_VENDOR_ID_INTEL);
pci_config_set_device_id(d->dev.config, PCI_DEVICE_ID_INTEL_82441);
d->dev.config[0x08] = 0x02; // revision
pci_config_set_class(d->dev.config, PCI_CLASS_BRIDGE_HOST);
d->dev.config[I440FX_SMRAM] = 0x02;
cpu_smm_register(&i440fx_set_smm, d);
return 0;
}
PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *pic, ram_addr_t ram_size)
{
DeviceState *dev;
PCIBus *b;
PCIDevice *d;
I440FXState *s;
PIIX3State *piix3;
dev = qdev_create(NULL, "i440FX-pcihost");
s = FROM_SYSBUS(I440FXState, sysbus_from_qdev(dev));
b = pci_bus_new(&s->busdev.qdev, NULL, 0);
s->bus = b;
qdev_init_nofail(dev);
d = pci_create_simple(b, 0, "i440FX");
*pi440fx_state = DO_UPCAST(PCII440FXState, dev, d);
piix3 = DO_UPCAST(PIIX3State, dev,
pci_create_simple_multifunction(b, -1, true, "PIIX3"));
piix3->pic = pic;
pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, piix3, PIIX_NUM_PIRQS);
(*pi440fx_state)->piix3 = piix3;
*piix3_devfn = piix3->dev.devfn;
ram_size = ram_size / 8 / 1024 / 1024;
if (ram_size > 255)
ram_size = 255;
(*pi440fx_state)->dev.config[0x57]=ram_size;
return b;
}
/* PIIX3 PCI to ISA bridge */
static void piix3_set_irq_pic(PIIX3State *piix3, int pic_irq)
{
qemu_set_irq(piix3->pic[pic_irq],
!!(piix3->pic_levels &
(((1UL << PIIX_NUM_PIRQS) - 1) <<
(pic_irq * PIIX_NUM_PIRQS))));
}
static void piix3_set_irq_level(PIIX3State *piix3, int pirq, int level,
bool propagate)
{
int pic_irq;
uint64_t mask;
pic_irq = piix3->dev.config[PIIX_PIRQC + pirq];
if (pic_irq >= PIIX_NUM_PIC_IRQS) {
return;
}
mask = 1ULL << ((pic_irq * PIIX_NUM_PIRQS) + pirq);
piix3->pic_levels &= ~mask;
piix3->pic_levels |= mask * !!level;
if (propagate) {
piix3_set_irq_pic(piix3, pic_irq);
}
}
static void piix3_set_irq(void *opaque, int pirq, int level)
{
PIIX3State *piix3 = opaque;
piix3_set_irq_level(piix3, pirq, level, true);
}
/* irq routing is changed. so rebuild bitmap */
static void piix3_update_irq_levels(PIIX3State *piix3)
{
int pirq;
piix3->pic_levels = 0;
for (pirq = 0; pirq < PIIX_NUM_PIRQS; pirq++) {
piix3_set_irq_level(piix3, pirq,
pci_bus_get_irq_level(piix3->dev.bus, pirq),
false);
}
}
static void piix3_write_config(PCIDevice *dev,
uint32_t address, uint32_t val, int len)
{
pci_default_write_config(dev, address, val, len);
if (ranges_overlap(address, len, PIIX_PIRQC, 4)) {
PIIX3State *piix3 = DO_UPCAST(PIIX3State, dev, dev);
int pic_irq;
piix3_update_irq_levels(piix3);
for (pic_irq = 0; pic_irq < PIIX_NUM_PIC_IRQS; pic_irq++) {
piix3_set_irq_pic(piix3, pic_irq);
}
}
}
static void piix3_reset(void *opaque)
{
PIIX3State *d = opaque;
uint8_t *pci_conf = d->dev.config;
pci_conf[0x04] = 0x07; // master, memory and I/O
pci_conf[0x05] = 0x00;
pci_conf[0x06] = 0x00;
pci_conf[0x07] = 0x02; // PCI_status_devsel_medium
pci_conf[0x4c] = 0x4d;
pci_conf[0x4e] = 0x03;
pci_conf[0x4f] = 0x00;
pci_conf[0x60] = 0x80;
pci_conf[0x61] = 0x80;
pci_conf[0x62] = 0x80;
pci_conf[0x63] = 0x80;
pci_conf[0x69] = 0x02;
pci_conf[0x70] = 0x80;
pci_conf[0x76] = 0x0c;
pci_conf[0x77] = 0x0c;
pci_conf[0x78] = 0x02;
pci_conf[0x79] = 0x00;
pci_conf[0x80] = 0x00;
pci_conf[0x82] = 0x00;
pci_conf[0xa0] = 0x08;
pci_conf[0xa2] = 0x00;
pci_conf[0xa3] = 0x00;
pci_conf[0xa4] = 0x00;
pci_conf[0xa5] = 0x00;
pci_conf[0xa6] = 0x00;
pci_conf[0xa7] = 0x00;
pci_conf[0xa8] = 0x0f;
pci_conf[0xaa] = 0x00;
pci_conf[0xab] = 0x00;
pci_conf[0xac] = 0x00;
pci_conf[0xae] = 0x00;
d->pic_levels = 0;
}
static int piix3_post_load(void *opaque, int version_id)
{
PIIX3State *piix3 = opaque;
piix3_update_irq_levels(piix3);
return 0;
}
static void piix3_pre_save(void *opaque)
{
int i;
PIIX3State *piix3 = opaque;
for (i = 0; i < ARRAY_SIZE(piix3->pci_irq_levels_vmstate); i++) {
piix3->pci_irq_levels_vmstate[i] =
pci_bus_get_irq_level(piix3->dev.bus, i);
}
}
static const VMStateDescription vmstate_piix3 = {
.name = "PIIX3",
.version_id = 3,
.minimum_version_id = 2,
.minimum_version_id_old = 2,
.post_load = piix3_post_load,
.pre_save = piix3_pre_save,
.fields = (VMStateField []) {
VMSTATE_PCI_DEVICE(dev, PIIX3State),
VMSTATE_INT32_ARRAY_V(pci_irq_levels_vmstate, PIIX3State,
PIIX_NUM_PIRQS, 3),
VMSTATE_END_OF_LIST()
}
};
static int piix3_initfn(PCIDevice *dev)
{
PIIX3State *d = DO_UPCAST(PIIX3State, dev, dev);
uint8_t *pci_conf;
isa_bus_new(&d->dev.qdev);
pci_conf = d->dev.config;
pci_config_set_vendor_id(pci_conf, PCI_VENDOR_ID_INTEL);
pci_config_set_device_id(pci_conf, PCI_DEVICE_ID_INTEL_82371SB_0); // 82371SB PIIX3 PCI-to-ISA bridge (Step A1)
pci_config_set_class(pci_conf, PCI_CLASS_BRIDGE_ISA);
qemu_register_reset(piix3_reset, d);
return 0;
}
static PCIDeviceInfo i440fx_info[] = {
{
.qdev.name = "i440FX",
.qdev.desc = "Host bridge",
.qdev.size = sizeof(PCII440FXState),
.qdev.vmsd = &vmstate_i440fx,
.qdev.no_user = 1,
.no_hotplug = 1,
.init = i440fx_initfn,
.config_write = i440fx_write_config,
},{
.qdev.name = "PIIX3",
.qdev.desc = "ISA bridge",
.qdev.size = sizeof(PIIX3State),
.qdev.vmsd = &vmstate_piix3,
.qdev.no_user = 1,
.no_hotplug = 1,
.init = piix3_initfn,
.config_write = piix3_write_config,
},{
/* end of list */
}
};
static SysBusDeviceInfo i440fx_pcihost_info = {
.init = i440fx_pcihost_initfn,
.qdev.name = "i440FX-pcihost",
.qdev.fw_name = "pci",
.qdev.size = sizeof(I440FXState),
.qdev.no_user = 1,
};
static void i440fx_register(void)
{
sysbus_register_withprop(&i440fx_pcihost_info);
pci_qdev_register_many(i440fx_info);
}
device_init(i440fx_register);