From 595a4f07d6bd18ba11c78b95d6a78089fee26eca Mon Sep 17 00:00:00 2001 From: Tiejun Chen Date: Wed, 15 Jul 2015 13:37:43 +0800 Subject: [PATCH] piix: create host bridge to passthrough Implement a pci host bridge specific to passthrough. Actually this just inherits the standard one. And we also just expose a minimal real host bridge pci configuration subset. [Replace pread with lseek and read to fix Windows build] Signed-off-by: Tiejun Chen Signed-off-by: Stefano Stabellini Acked-by: Michael S. Tsirkin --- hw/pci-host/piix.c | 85 ++++++++++++++++++++++++++++++++++++++++++++ include/hw/i386/pc.h | 2 ++ 2 files changed, 87 insertions(+) diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c index e19badb23c..1fb71c8081 100644 --- a/hw/pci-host/piix.c +++ b/hw/pci-host/piix.c @@ -739,6 +739,90 @@ static const TypeInfo i440fx_info = { .class_init = i440fx_class_init, }; +/* IGD Passthrough Host Bridge. */ +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[] = { + {0x08, 2}, /* revision id */ + {0x2c, 2}, /* sybsystem vendor id */ + {0x2e, 2}, /* sybsystem id */ + {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 int host_pci_config_read(int pos, int len, uint32_t val) +{ + char path[PATH_MAX]; + int config_fd; + ssize_t size = sizeof(path); + /* Access real host bridge. */ + int rc = snprintf(path, size, "/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s", + 0, 0, 0, 0, "config"); + + if (rc >= size || rc < 0) { + return -ENODEV; + } + + config_fd = open(path, O_RDWR); + if (config_fd < 0) { + return -ENODEV; + } + + if (lseek(config_fd, pos, SEEK_SET) != pos) { + return -errno; + } + do { + rc = read(config_fd, (uint8_t *)&val, len); + } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); + if (rc != len) { + return -errno; + } + + return 0; +} + +static int igd_pt_i440fx_initfn(struct PCIDevice *pci_dev) +{ + uint32_t val = 0; + int rc, i, num; + int pos, len; + + num = ARRAY_SIZE(igd_host_bridge_infos); + for (i = 0; i < num; i++) { + pos = igd_host_bridge_infos[i].offset; + len = igd_host_bridge_infos[i].len; + rc = host_pci_config_read(pos, len, val); + if (rc) { + return -ENODEV; + } + pci_default_write_config(pci_dev, pos, val, len); + } + + return 0; +} + +static void igd_passthrough_i440fx_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + PCIDeviceClass *k = PCI_DEVICE_CLASS(klass); + + k->init = igd_pt_i440fx_initfn; + 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 const char *i440fx_pcihost_root_bus_path(PCIHostState *host_bridge, PCIBus *rootbus) { @@ -780,6 +864,7 @@ static const TypeInfo i440fx_pcihost_info = { static void i440fx_register_types(void) { type_register_static(&i440fx_info); + type_register_static(&igd_passthrough_i440fx_info); type_register_static(&piix3_pci_type_info); type_register_static(&piix3_info); type_register_static(&piix3_xen_info); diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h index 6edacbd8fc..5cda2a3ff6 100644 --- a/include/hw/i386/pc.h +++ b/include/hw/i386/pc.h @@ -222,6 +222,8 @@ typedef struct PCII440FXState PCII440FXState; #define TYPE_I440FX_PCI_HOST_BRIDGE "i440FX-pcihost" #define TYPE_I440FX_PCI_DEVICE "i440FX" +#define TYPE_IGD_PASSTHROUGH_I440FX_PCI_DEVICE "igd-passthrough-i440FX" + PCIBus *i440fx_init(const char *host_type, const char *pci_type, PCII440FXState **pi440fx_state, int *piix_devfn, ISABus **isa_bus, qemu_irq *pic,