[PATCH v2 11/17] fs/stlmfs: Document alternative ioctl based binary interface
From: Cristian Marussi <cristian.marussi@arm.com>
Date: 2026-01-14 11:48:03
Also in:
arm-scmi, linux-fsdevel, lkml
Subsystem:
documentation, the rest · Maintainers:
Jonathan Corbet, Linus Torvalds
Document the additionally provided special files and their usage in the context of the alternative binary ioctl-based interface. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> --- Documentation/filesystems/stlmfs.rst | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)
diff --git a/Documentation/filesystems/stlmfs.rst b/Documentation/filesystems/stlmfs.rst
index 7ea8878098f7..5c23f7e5f12c 100644
--- a/Documentation/filesystems/stlmfs.rst
+++ b/Documentation/filesystems/stlmfs.rst@@ -112,6 +112,7 @@ the following directory structure:: |-- all_des_enable |-- all_des_tstamp_enable |-- available_update_intervals_ms + |-- control |-- current_update_interval_ms |-- de_implementation_version |-- des/
@@ -129,6 +130,10 @@ the following directory structure:: |-- tlm_enable `-- version +.. Note:: + The control/ special file can be used to use the alternative + binary interface described in include/uapi/linux/scmi.h + Each subdirectory is defined as follows. des/
@@ -189,6 +194,7 @@ values, as in:: scmi_tlm_0/groups/0/ |-- available_update_intervals_ms |-- composing_des + |-- control |-- current_update_interval_ms |-- des_bulk_read |-- des_single_sample_read
@@ -196,3 +202,21 @@ values, as in:: |-- intervals_discrete `-- tstamp_enable +Alternative Binary Interfaces - Special files +============================================= + +Special files are populated across the filesystem so as to implement the support +of more performant alternative binary interfaces that can be used instead of the +main human readable ABI. + +IOCTLs Interface +---------------- + +The ioctl-based interface is detailed in:: + + include/uapi/linux/smci.h + +The filesystem provides special files named *control/* to be used with the +ioctl interface mentioned above: note that the behaviour of some of the ioctls +is dependent on which *control/* file is used to invoke them (as detailed in the +UAPI header above).
--
2.52.0