qemu/hw/pci-host/xen_igd_pt.c

120 lines
3.8 KiB
C

/*
* QEMU Intel IGD Passthrough Host Bridge Emulation
*
* Copyright (c) 2006 Fabrice Bellard
*
* SPDX-License-Identifier: MIT
*
* 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 "qemu/osdep.h"
#include "hw/pci/pci.h"
#include "hw/pci/pci_host.h"
#include "hw/pci-host/i440fx.h"
#include "qapi/error.h"
typedef struct {
uint8_t offset;
uint8_t len;
} IGDHostInfo;
/* Here we just expose minimal host bridge offset subset. */
static const IGDHostInfo igd_host_bridge_infos[] = {
{PCI_REVISION_ID, 2},
{PCI_SUBSYSTEM_VENDOR_ID, 2},
{PCI_SUBSYSTEM_ID, 2},
{0x50, 2}, /* SNB: processor graphics control register */
{0x52, 2}, /* processor graphics control register */
{0xa4, 4}, /* SNB: graphics base of stolen memory */
{0xa8, 4}, /* SNB: base of GTT stolen memory */
};
static void host_pci_config_read(int pos, int len, uint32_t *val, Error **errp)
{
int rc, config_fd;
/* Access real host bridge. */
char *path = g_strdup_printf("/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s",
0, 0, 0, 0, "config");
config_fd = open(path, O_RDWR);
if (config_fd < 0) {
error_setg_errno(errp, errno, "Failed to open: %s", path);
goto out;
}
if (lseek(config_fd, pos, SEEK_SET) != pos) {
error_setg_errno(errp, errno, "Failed to seek: %s", path);
goto out_close_fd;
}
do {
rc = read(config_fd, (uint8_t *)val, len);
} while (rc < 0 && (errno == EINTR || errno == EAGAIN));
if (rc != len) {
error_setg_errno(errp, errno, "Failed to read: %s", path);
}
out_close_fd:
close(config_fd);
out:
g_free(path);
}
static void igd_pt_i440fx_realize(PCIDevice *pci_dev, Error **errp)
{
ERRP_GUARD();
uint32_t val = 0;
size_t i;
int pos, len;
for (i = 0; i < ARRAY_SIZE(igd_host_bridge_infos); i++) {
pos = igd_host_bridge_infos[i].offset;
len = igd_host_bridge_infos[i].len;
host_pci_config_read(pos, len, &val, errp);
if (*errp) {
return;
}
pci_default_write_config(pci_dev, pos, val, len);
}
}
static void igd_passthrough_i440fx_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
k->realize = igd_pt_i440fx_realize;
dc->desc = "IGD Passthrough Host bridge";
}
static const TypeInfo igd_passthrough_i440fx_info = {
.name = TYPE_IGD_PASSTHROUGH_I440FX_PCI_DEVICE,
.parent = TYPE_I440FX_PCI_DEVICE,
.instance_size = sizeof(PCII440FXState),
.class_init = igd_passthrough_i440fx_class_init,
};
static void igd_pt_i440fx_register_types(void)
{
type_register_static(&igd_passthrough_i440fx_info);
}
type_init(igd_pt_i440fx_register_types)