[PATCH v9 4/5] Documentation/gpu: Add fdinfo meanings of panthor-*-memory tags

Adrián Larumbe
2025-01-23T22:54:52Z

A previous commit enabled display of driver-internal kernel BO sizes
through the device file's fdinfo interface.

Expand the description of the relevant driver-specific key:value pairs
with the definitions of the new panthor-*-memory ones.

Reviewed-by: Mihail Atanassov <mihail.atanassov@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
---
Documentation/gpu/panthor.rst | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/Documentation/gpu/panthor.rst b/Documentation/gpu/panthor.rst
index 3f8979fa2b86..7a841741278f 100644
--- a/Documentation/gpu/panthor.rst
+++ b/Documentation/gpu/panthor.rst
@@ -26,6 +26,8 @@ the currently possible format options:
drm-cycles-panthor: 94439687187
drm-maxfreq-panthor: 1000000000 Hz
drm-curfreq-panthor: 1000000000 Hz
+ panthor-resident-memory: 10396 KiB
+ panthor-active-memory: 10396 KiB
drm-total-memory: 16480 KiB
drm-shared-memory: 0
drm-active-memory: 16200 KiB
@@ -44,3 +46,11 @@ driver by writing into the appropriate sysfs node::

Where `N` is a bit mask where cycle and timestamp sampling are respectively
enabled by the first and second bits.
+
+Possible `panthor-*-memory` keys are: `active` and `resident`.
+These values convey the sizes of the internal driver-owned shmem BO's that
+aren't exposed to user-space through a DRM handle, like queue ring buffers,
+sync object arrays and heap chunks. Because they are all allocated and pinned
+at creation time, only `panthor-resident-memory` is necessary to tell us their
+size. `panthor-active-memory` shows the size of kernel BO's associated with
+VM's and groups currently being scheduled for execution by the GPU.
--
2.47.1