| Linus Walleij | 301d2d8 | 2013-02-13 15:21:21 +0100 | [diff] [blame] | 1 | PCI bus bridges have standardized Device Tree bindings: |
| 2 | |
| 3 | PCI Bus Binding to: IEEE Std 1275-1994 |
| Bjorn Helgaas | f517256 | 2015-10-20 16:03:03 -0500 | [diff] [blame] | 4 | http://www.firmware.org/1275/bindings/pci/pci2_1.pdf |
| Linus Walleij | 301d2d8 | 2013-02-13 15:21:21 +0100 | [diff] [blame] | 5 | |
| 6 | And for the interrupt mapping part: |
| 7 | |
| 8 | Open Firmware Recommended Practice: Interrupt Mapping |
| Bjorn Helgaas | f517256 | 2015-10-20 16:03:03 -0500 | [diff] [blame] | 9 | http://www.firmware.org/1275/practice/imap/imap0_9d.pdf |
| Lucas Stach | 2801f72 | 2014-11-06 16:23:20 +0100 | [diff] [blame] | 10 | |
| 11 | Additionally to the properties specified in the above standards a host bridge |
| 12 | driver implementation may support the following properties: |
| 13 | |
| 14 | - linux,pci-domain: |
| 15 | If present this property assigns a fixed PCI domain number to a host bridge, |
| 16 | otherwise an unstable (across boots) unique number will be assigned. |
| 17 | It is required to either not set this property at all or set it for all |
| 18 | host bridges in the system, otherwise potentially conflicting domain numbers |
| 19 | may be assigned to root buses behind different host bridges. The domain |
| 20 | number for each host bridge in the system must be unique. |
| Shawn Lin | 2fa3915 | 2016-11-14 15:20:57 -0600 | [diff] [blame] | 21 | - max-link-speed: |
| 22 | If present this property specifies PCI gen for link capability. Host |
| 23 | drivers could add this as a strategy to avoid unnecessary operation for |
| 24 | unsupported link speed, for instance, trying to do training for |
| 25 | unsupported link speed, etc. Must be '4' for gen4, '3' for gen3, '2' |
| 26 | for gen2, and '1' for gen1. Any other values are invalid. |
