diff options
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/pci.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 91138cbeb853..e7a3917ed389 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5289,6 +5289,38 @@ u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed, } /** + * pcie_print_link_status - Report the PCI device's link speed and width + * @dev: PCI device to query + * + * Report the available bandwidth at the device. If this is less than the + * device is capable of, report the device's maximum possible bandwidth and + * the upstream link that limits its performance to less than that. + */ +void pcie_print_link_status(struct pci_dev *dev) +{ + enum pcie_link_width width, width_cap; + enum pci_bus_speed speed, speed_cap; + struct pci_dev *limiting_dev = NULL; + u32 bw_avail, bw_cap; + + bw_cap = pcie_bandwidth_capable(dev, &speed_cap, &width_cap); + bw_avail = pcie_bandwidth_available(dev, &limiting_dev, &speed, &width); + + if (bw_avail >= bw_cap) + pci_info(dev, "%u.%03u Gb/s available bandwidth (%s x%d link)\n", + bw_cap / 1000, bw_cap % 1000, + PCIE_SPEED2STR(speed_cap), width_cap); + else + pci_info(dev, "%u.%03u Gb/s available bandwidth, limited by %s x%d link at %s (capable of %u.%03u Gb/s with %s x%d link)\n", + bw_avail / 1000, bw_avail % 1000, + PCIE_SPEED2STR(speed), width, + limiting_dev ? pci_name(limiting_dev) : "<unknown>", + bw_cap / 1000, bw_cap % 1000, + PCIE_SPEED2STR(speed_cap), width_cap); +} +EXPORT_SYMBOL(pcie_print_link_status); + +/** * pci_select_bars - Make BAR mask from the type of resource * @dev: the PCI device for which BAR mask is made * @flags: resource type mask to be selected |