/sys/class/rapidio_port
| Field | Value |
|---|---|
| Subsystem | RapidIO subsystem (mport = Master Port view of on-chip RapidIO controllers and PCIe-to-RapidIO bridges); contacts Matt Porter, Alexandre Bounine; implementation file not in cached tree |
| Config gate | not verifiable from cached tree (no drivers/Kconfig cached) |
| ABI documentation | Documentation/ABI/testing/sysfs-class-rapidio (3 What: entries, all under /sys/class/rapidio_port/) |
| Since | v3.15 (Apr 2014, both attribute entries) |
| Live (5.10.134 host) | class absent: /sys/class/rapidio_port does not exist in this container |
| Ledger ID | SYSC-rapidio_port |
What it represents
The class of RapidIO Master Ports: “On-chip RapidIO controllers and PCIe-to-RapidIO bridges (referenced as ‘Master Port’ or ‘mport’) are presented in sysfs as the special class of devices: rapidio_port” (ABI). Directories are named rapidioN where N is the mport ID registered with the RapidIO subsystem; the ABI warns that an mport ID is not the RapidIO destination ID of the device. The two attributes report the transport system size and the port’s own destination ID.
Relationship to the device model
The ABI includes a live ls -l of /sys/class/rapidio_port/rapidio0/ showing the standard class furniture (device -> ../../../0000:01:00.0, subsystem -> …/class/rapidio_port, uevent, power/) plus child RapidIO device directories named like 00:e:0001 and 00:s:0003: “After enumeration or discovery was performed for a given mport device, the corresponding subdirectory will also contain subdirectories for each child RapidIO device connected to the mport.” The child fabric topology is thus attached to the mport’s class directory.
Attributes
| Attribute | R/W | Unit/format | Conditional? | Source |
|---|---|---|---|---|
| sys_size | RO | RapidIO common transport system size: 0 small (8-bit destination ID, max 256 devices), 1 large (16-bit, max 65536 devices) | always | ABI testing sysfs-class-rapidio, v3.15 |
| port_destid | RO | destination ID of the mport; 0xFFFFFFFF means none assigned yet; enumerating mports get one via the “hdid=…” rapidio module parameter | always | ABI testing sysfs-class-rapidio, v3.15 |
<child device dirs> | – | per-child RapidIO device directories (e.g. 00:e:0001) appear after enumeration/discovery | post-enumeration | ABI example listing |
Safety and writes
Both documented attributes are read-only; the ABI records no writable file in this class, so enumeration and discovery are driven by module parameters and the RapidIO subsystem rather than sysfs writes. RapidIO hardware is absent from this x86 container, so the class does not exist on the host and no live value was read.
References
Documentation/ABI/testing/sysfs-class-rapidio(cached copy; class paths /sys/class/rapidio_port/)- https://github.com/torvalds/linux/blob/master/Documentation/ABI/testing/sysfs-class-rapidio
- sysfs-attrs.json entry
rapidio_port(2 paths); live enumeration: class absent, kernel 5.10.134 - Coverage: ledger