diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/pci/pci.c | 129 |
1 files changed, 105 insertions, 24 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index cbbf197df8..dff09e4892 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -142,8 +142,8 @@ enum pcie_bus_config_types pcie_bus_config = PCIE_BUS_DEFAULT; * the dfl or actual value as it sees fit. Don't forget this is * measured in 32-bit words, not bytes. */ -u8 pci_dfl_cache_line_size = L1_CACHE_BYTES >> 2; -u8 pci_cache_line_size; +u8 pci_dfl_cache_line_size __ro_after_init = L1_CACHE_BYTES >> 2; +u8 pci_cache_line_size __ro_after_init ; /* * If we set up a device for bus mastering, we need to check the latency @@ -2116,20 +2116,6 @@ static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags) } /** - * pci_enable_device_io - Initialize a device for use with IO space - * @dev: PCI device to be initialized - * - * Initialize device before it's used by a driver. Ask low-level code - * to enable I/O resources. Wake up the device if it was suspended. - * Beware, this function can fail. - */ -int pci_enable_device_io(struct pci_dev *dev) -{ - return pci_enable_device_flags(dev, IORESOURCE_IO); -} -EXPORT_SYMBOL(pci_enable_device_io); - -/** * pci_enable_device_mem - Initialize a device for use with Memory space * @dev: PCI device to be initialized * @@ -4642,9 +4628,10 @@ int pcie_retrain_link(struct pci_dev *pdev, bool use_lt) /* * Ensure the updated LNKCTL parameters are used during link - * training by checking that there is no ongoing link training to - * avoid LTSSM race as recommended in Implementation Note at the - * end of PCIe r6.0.1 sec 7.5.3.7. + * training by checking that there is no ongoing link training that + * may have started before link parameters were changed, so as to + * avoid LTSSM race as recommended in Implementation Note at the end + * of PCIe r6.1 sec 7.5.3.7. */ rc = pcie_wait_for_link_status(pdev, true, false); if (rc) @@ -4766,7 +4753,7 @@ static int pci_bus_max_d3cold_delay(const struct pci_bus *bus) */ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type) { - struct pci_dev *child; + struct pci_dev *child __free(pci_dev_put) = NULL; int delay; if (pci_dev_is_disconnected(dev)) @@ -4795,8 +4782,8 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type) return 0; } - child = list_first_entry(&dev->subordinate->devices, struct pci_dev, - bus_list); + child = pci_dev_get(list_first_entry(&dev->subordinate->devices, + struct pci_dev, bus_list)); up_read(&pci_bus_sem); /* @@ -4944,16 +4931,96 @@ static int pci_dev_reset_slot_function(struct pci_dev *dev, bool probe) return pci_reset_hotplug_slot(dev->slot->hotplug, probe); } +static u16 cxl_port_dvsec(struct pci_dev *dev) +{ + return pci_find_dvsec_capability(dev, PCI_VENDOR_ID_CXL, + PCI_DVSEC_CXL_PORT); +} + +static bool cxl_sbr_masked(struct pci_dev *dev) +{ + u16 dvsec, reg; + int rc; + + dvsec = cxl_port_dvsec(dev); + if (!dvsec) + return false; + + rc = pci_read_config_word(dev, dvsec + PCI_DVSEC_CXL_PORT_CTL, ®); + if (rc || PCI_POSSIBLE_ERROR(reg)) + return false; + + /* + * Per CXL spec r3.1, sec 8.1.5.2, when "Unmask SBR" is 0, the SBR + * bit in Bridge Control has no effect. When 1, the Port generates + * hot reset when the SBR bit is set to 1. + */ + if (reg & PCI_DVSEC_CXL_PORT_CTL_UNMASK_SBR) + return false; + + return true; +} + static int pci_reset_bus_function(struct pci_dev *dev, bool probe) { + struct pci_dev *bridge = pci_upstream_bridge(dev); int rc; + /* + * If "dev" is below a CXL port that has SBR control masked, SBR + * won't do anything, so return error. + */ + if (bridge && cxl_sbr_masked(bridge)) { + if (probe) + return 0; + + return -ENOTTY; + } + rc = pci_dev_reset_slot_function(dev, probe); if (rc != -ENOTTY) return rc; return pci_parent_bus_reset(dev, probe); } +static int cxl_reset_bus_function(struct pci_dev *dev, bool probe) +{ + struct pci_dev *bridge; + u16 dvsec, reg, val; + int rc; + + bridge = pci_upstream_bridge(dev); + if (!bridge) + return -ENOTTY; + + dvsec = cxl_port_dvsec(bridge); + if (!dvsec) + return -ENOTTY; + + if (probe) + return 0; + + rc = pci_read_config_word(bridge, dvsec + PCI_DVSEC_CXL_PORT_CTL, ®); + if (rc) + return -ENOTTY; + + if (reg & PCI_DVSEC_CXL_PORT_CTL_UNMASK_SBR) { + val = reg; + } else { + val = reg | PCI_DVSEC_CXL_PORT_CTL_UNMASK_SBR; + pci_write_config_word(bridge, dvsec + PCI_DVSEC_CXL_PORT_CTL, + val); + } + + rc = pci_reset_bus_function(dev, probe); + + if (reg != val) + pci_write_config_word(bridge, dvsec + PCI_DVSEC_CXL_PORT_CTL, + reg); + + return rc; +} + void pci_dev_lock(struct pci_dev *dev) { /* block PM suspend, driver probe, etc. */ @@ -5038,6 +5105,7 @@ static const struct pci_reset_fn_method pci_reset_fn_methods[] = { { pci_af_flr, .name = "af_flr" }, { pci_pm_reset, .name = "pm" }, { pci_reset_bus_function, .name = "bus" }, + { cxl_reset_bus_function, .name = "cxl_bus" }, }; static ssize_t reset_method_show(struct device *dev, @@ -5262,11 +5330,20 @@ void pci_init_reset_methods(struct pci_dev *dev) */ int pci_reset_function(struct pci_dev *dev) { + struct pci_dev *bridge; int rc; if (!pci_reset_supported(dev)) return -ENOTTY; + /* + * If there's no upstream bridge, no locking is needed since there is + * no upstream bridge configuration to hold consistent. + */ + bridge = pci_upstream_bridge(dev); + if (bridge) + pci_dev_lock(bridge); + pci_dev_lock(dev); pci_dev_save_and_disable(dev); @@ -5275,6 +5352,9 @@ int pci_reset_function(struct pci_dev *dev) pci_dev_restore(dev); pci_dev_unlock(dev); + if (bridge) + pci_dev_unlock(bridge); + return rc; } EXPORT_SYMBOL_GPL(pci_reset_function); @@ -6082,8 +6162,9 @@ EXPORT_SYMBOL(pcie_get_width_cap); * and width, multiplying them, and applying encoding overhead. The result * is in Mb/s, i.e., megabits/second of raw bandwidth. */ -u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed, - enum pcie_link_width *width) +static u32 pcie_bandwidth_capable(struct pci_dev *dev, + enum pci_bus_speed *speed, + enum pcie_link_width *width) { *speed = pcie_get_speed_cap(dev); *width = pcie_get_width_cap(dev); |