| 1 | /* |
| 2 | * QEMU Intel IGD Passthrough Host Bridge Emulation |
| 3 | * |
| 4 | * Copyright (c) 2006 Fabrice Bellard |
| 5 | * |
| 6 | * SPDX-License-Identifier: MIT |
| 7 | * |
| 8 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 9 | * of this software and associated documentation files (the "Software"), to deal |
| 10 | * in the Software without restriction, including without limitation the rights |
| 11 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 12 | * copies of the Software, and to permit persons to whom the Software is |
| 13 | * furnished to do so, subject to the following conditions: |
| 14 | * |
| 15 | * The above copyright notice and this permission notice shall be included in |
| 16 | * all copies or substantial portions of the Software. |
| 17 | * |
| 18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 20 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 21 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 22 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 23 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 24 | * THE SOFTWARE. |
| 25 | */ |
| 26 | |
| 27 | #include "qemu/osdep.h" |
| 28 | #include "hw/pci/pci.h" |
| 29 | #include "hw/pci/pci_host.h" |
| 30 | #include "hw/pci-host/i440fx.h" |
| 31 | #include "qapi/error.h" |
| 32 | |
| 33 | typedef struct { |
| 34 | uint8_t offset; |
| 35 | uint8_t len; |
| 36 | } IGDHostInfo; |
| 37 | |
| 38 | /* Here we just expose minimal host bridge offset subset. */ |
| 39 | static const IGDHostInfo igd_host_bridge_infos[] = { |
| 40 | {PCI_REVISION_ID, 2}, |
| 41 | {PCI_SUBSYSTEM_VENDOR_ID, 2}, |
| 42 | {PCI_SUBSYSTEM_ID, 2}, |
| 43 | {0x50, 2}, /* SNB: processor graphics control register */ |
| 44 | {0x52, 2}, /* processor graphics control register */ |
| 45 | {0xa4, 4}, /* SNB: graphics base of stolen memory */ |
| 46 | {0xa8, 4}, /* SNB: base of GTT stolen memory */ |
| 47 | }; |
| 48 | |
| 49 | static void host_pci_config_read(int pos, int len, uint32_t *val, Error **errp) |
| 50 | { |
| 51 | int rc, config_fd; |
| 52 | /* Access real host bridge. */ |
| 53 | char *path = g_strdup_printf("/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s", |
| 54 | 0, 0, 0, 0, "config"); |
| 55 | |
| 56 | config_fd = open(path, O_RDWR); |
| 57 | if (config_fd < 0) { |
| 58 | error_setg_file_open(errp, errno, path); |
| 59 | goto out; |
| 60 | } |
| 61 | |
| 62 | if (lseek(config_fd, pos, SEEK_SET) != pos) { |
| 63 | error_setg_errno(errp, errno, "Failed to seek: %s", path); |
| 64 | goto out_close_fd; |
| 65 | } |
| 66 | |
| 67 | do { |
| 68 | rc = read(config_fd, (uint8_t *)val, len); |
| 69 | } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); |
| 70 | if (rc != len) { |
| 71 | error_setg_errno(errp, errno, "Failed to read: %s", path); |
| 72 | } |
| 73 | |
| 74 | out_close_fd: |
| 75 | close(config_fd); |
| 76 | out: |
| 77 | g_free(path); |
| 78 | } |
| 79 | |
| 80 | static void igd_pt_i440fx_realize(PCIDevice *pci_dev, Error **errp) |
| 81 | { |
| 82 | ERRP_GUARD(); |
| 83 | uint32_t val = 0; |
| 84 | size_t i; |
| 85 | int pos, len; |
| 86 | |
| 87 | for (i = 0; i < ARRAY_SIZE(igd_host_bridge_infos); i++) { |
| 88 | pos = igd_host_bridge_infos[i].offset; |
| 89 | len = igd_host_bridge_infos[i].len; |
| 90 | host_pci_config_read(pos, len, &val, errp); |
| 91 | if (*errp) { |
| 92 | return; |
| 93 | } |
| 94 | pci_default_write_config(pci_dev, pos, val, len); |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | static void igd_passthrough_i440fx_class_init(ObjectClass *klass, |
| 99 | const void *data) |
| 100 | { |
| 101 | DeviceClass *dc = DEVICE_CLASS(klass); |
| 102 | PCIDeviceClass *k = PCI_DEVICE_CLASS(klass); |
| 103 | |
| 104 | k->realize = igd_pt_i440fx_realize; |
| 105 | dc->desc = "IGD Passthrough Host bridge"; |
| 106 | } |
| 107 | |
| 108 | static const TypeInfo igd_passthrough_i440fx_info = { |
| 109 | .name = TYPE_IGD_PASSTHROUGH_I440FX_PCI_DEVICE, |
| 110 | .parent = TYPE_I440FX_PCI_DEVICE, |
| 111 | .instance_size = sizeof(PCII440FXState), |
| 112 | .class_init = igd_passthrough_i440fx_class_init, |
| 113 | }; |
| 114 | |
| 115 | static void igd_pt_i440fx_register_types(void) |
| 116 | { |
| 117 | type_register_static(&igd_passthrough_i440fx_info); |
| 118 | } |
| 119 | |
| 120 | type_init(igd_pt_i440fx_register_types) |