diff options
| -rw-r--r-- | hw/pci/pci.c | 4 | ||||
| -rw-r--r-- | hw/pci/pcie.c | 39 | ||||
| -rw-r--r-- | include/hw/pci/pci.h | 13 | ||||
| -rw-r--r-- | include/hw/pci/pcie.h | 1 |
4 files changed, 57 insertions, 0 deletions
diff --git a/hw/pci/pci.c b/hw/pci/pci.c index efb5ce196f..d831fa0a36 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -1353,6 +1353,10 @@ uint32_t pci_default_read_config(PCIDevice *d, { uint32_t val = 0; + if (pci_is_express_downstream_port(d) && + ranges_overlap(address, len, d->exp.exp_cap + PCI_EXP_LNKSTA, 2)) { + pcie_sync_bridge_lnk(d); + } memcpy(&val, d->config + address, len); return le32_to_cpu(val); } diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c index aef84c665b..6891deb711 100644 --- a/hw/pci/pcie.c +++ b/hw/pci/pcie.c @@ -741,6 +741,45 @@ void pcie_add_capability(PCIDevice *dev, memset(dev->cmask + offset, 0xFF, size); } +/* + * Sync the PCIe Link Status negotiated speed and width of a bridge with the + * downstream device. If downstream device is not present, re-write with the + * Link Capability fields. Limit width and speed to bridge capabilities for + * compatibility. Use config_read to access the downstream device since it + * could be an assigned device with volatile link information. + */ +void pcie_sync_bridge_lnk(PCIDevice *bridge_dev) +{ + PCIBridge *br = PCI_BRIDGE(bridge_dev); + PCIBus *bus = pci_bridge_get_sec_bus(br); + PCIDevice *target = bus->devices[0]; + uint8_t *exp_cap = bridge_dev->config + bridge_dev->exp.exp_cap; + uint16_t lnksta, lnkcap = pci_get_word(exp_cap + PCI_EXP_LNKCAP); + + if (!target || !target->exp.exp_cap) { + lnksta = lnkcap; + } else { + lnksta = target->config_read(target, + target->exp.exp_cap + PCI_EXP_LNKSTA, + sizeof(lnksta)); + + if ((lnksta & PCI_EXP_LNKSTA_NLW) > (lnkcap & PCI_EXP_LNKCAP_MLW)) { + lnksta &= ~PCI_EXP_LNKSTA_NLW; + lnksta |= lnkcap & PCI_EXP_LNKCAP_MLW; + } + + if ((lnksta & PCI_EXP_LNKSTA_CLS) > (lnkcap & PCI_EXP_LNKCAP_SLS)) { + lnksta &= ~PCI_EXP_LNKSTA_CLS; + lnksta |= lnkcap & PCI_EXP_LNKCAP_SLS; + } + } + + pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKSTA, + PCI_EXP_LNKSTA_CLS | PCI_EXP_LNKSTA_NLW); + pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA, lnksta & + (PCI_EXP_LNKSTA_CLS | PCI_EXP_LNKSTA_NLW)); +} + /************************************************************************** * pci express extended capability helper functions */ diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h index e6514bba23..eb12fa112e 100644 --- a/include/hw/pci/pci.h +++ b/include/hw/pci/pci.h @@ -737,6 +737,19 @@ static inline int pci_is_express(const PCIDevice *d) return d->cap_present & QEMU_PCI_CAP_EXPRESS; } +static inline int pci_is_express_downstream_port(const PCIDevice *d) +{ + uint8_t type; + + if (!pci_is_express(d) || !d->exp.exp_cap) { + return 0; + } + + type = pcie_cap_get_type(d); + + return type == PCI_EXP_TYPE_DOWNSTREAM || type == PCI_EXP_TYPE_ROOT_PORT; +} + static inline uint32_t pci_config_size(const PCIDevice *d) { return pci_is_express(d) ? PCIE_CONFIG_SPACE_SIZE : PCI_CONFIG_SPACE_SIZE; diff --git a/include/hw/pci/pcie.h b/include/hw/pci/pcie.h index b71e369703..1976909ab4 100644 --- a/include/hw/pci/pcie.h +++ b/include/hw/pci/pcie.h @@ -126,6 +126,7 @@ uint16_t pcie_find_capability(PCIDevice *dev, uint16_t cap_id); void pcie_add_capability(PCIDevice *dev, uint16_t cap_id, uint8_t cap_ver, uint16_t offset, uint16_t size); +void pcie_sync_bridge_lnk(PCIDevice *dev); void pcie_ari_init(PCIDevice *dev, uint16_t offset, uint16_t nextfn); void pcie_dev_ser_num_init(PCIDevice *dev, uint16_t offset, uint64_t ser_num); |