summaryrefslogtreecommitdiff
path: root/Documentation/driver-api
diff options
context:
space:
mode:
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-08-24 15:00:14 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-08-24 15:00:14 +0300
commit704e2c6107f1a5353a1038bac137dda0df2a6dd0 (patch)
tree8f9bddd49fb2b483957032eff9c37b1bfac23f01 /Documentation/driver-api
parenteb176cb46191f20314878222d8186106e23cb711 (diff)
parent6ac3f01201fa1c453fc8a8ce5a7208da9cca254d (diff)
downloadlinux-704e2c6107f1a5353a1038bac137dda0df2a6dd0.tar.xz
Merge tag 'icc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/djakov/icc into char-misc-next
Georgi writes: interconnect changes for 6.6 This pull request contains the interconnect changes for the 6.6-rc1 merge window which is a mix of core and driver changes with the following highlights: Core changes: - New generic test client driver that allows issuing bandwidth requests between endpoints via debugfs. - Annotate all structs with flexible array members with the __counted_by attribute. - Introduce new icc_bw_lock for cases where we need to serialize bandwidth aggregation and update to decouple that from paths that require memory allocation. Driver changes: - Move the Qualcomm SMD RPM bus-clocks from CCF to interconnect framework where they actually belong. This brings power management improvements and reduces the overhead and layering. These changes are in immutable branch that is being pulled also into the qcom tree. - Fixes for QUP nodes on SM8250. - Enable sync_state and keepalive for QCM2290. - Enable sync_state for SM8450. - Improve enable_mask-based BCMs handling and fix some bugs. - Add compatible string for the OSM-L3 on SDM670. - Add compatible strings for SC7180, SM8250 and SM6350 bandwidth monitors. - Expand and retire the DEFINE_QNODE and DEFINE_QBCM macros, which have become ugly beasts with many different arguments. Signed-off-by: Georgi Djakov <djakov@kernel.org> * tag 'icc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/djakov/icc: (64 commits) interconnect: Add debugfs test client interconnect: Reintroduce icc_get() debugfs: Add write support to debugfs_create_str() interconnect: qcom: icc-rpmh: Retire DEFINE_QBCM interconnect: qcom: sm8350: Retire DEFINE_QBCM interconnect: qcom: sm8250: Retire DEFINE_QBCM interconnect: qcom: sm8150: Retire DEFINE_QBCM interconnect: qcom: sm6350: Retire DEFINE_QBCM interconnect: qcom: sdx65: Retire DEFINE_QBCM interconnect: qcom: sdx55: Retire DEFINE_QBCM interconnect: qcom: sdm845: Retire DEFINE_QBCM interconnect: qcom: sdm670: Retire DEFINE_QBCM interconnect: qcom: sc7180: Retire DEFINE_QBCM interconnect: qcom: icc-rpmh: Retire DEFINE_QNODE interconnect: qcom: sm8350: Retire DEFINE_QNODE interconnect: qcom: sm8250: Retire DEFINE_QNODE interconnect: qcom: sm8150: Retire DEFINE_QNODE interconnect: qcom: sm6350: Retire DEFINE_QNODE interconnect: qcom: sdx65: Retire DEFINE_QNODE interconnect: qcom: sdx55: Retire DEFINE_QNODE ...
Diffstat (limited to 'Documentation/driver-api')
-rw-r--r--Documentation/driver-api/interconnect.rst25
1 files changed, 25 insertions, 0 deletions
diff --git a/Documentation/driver-api/interconnect.rst b/Documentation/driver-api/interconnect.rst
index 5ed4f57a6bac..a92d0f277a1f 100644
--- a/Documentation/driver-api/interconnect.rst
+++ b/Documentation/driver-api/interconnect.rst
@@ -113,3 +113,28 @@ through dot to generate diagrams in many graphical formats::
$ cat /sys/kernel/debug/interconnect/interconnect_graph | \
dot -Tsvg > interconnect_graph.svg
+
+The ``test-client`` directory provides interfaces for issuing BW requests to
+any arbitrary path. Note that for safety reasons, this feature is disabled by
+default without a Kconfig to enable it. Enabling it requires code changes to
+``#define INTERCONNECT_ALLOW_WRITE_DEBUGFS``. Example usage::
+
+ cd /sys/kernel/debug/interconnect/test-client/
+
+ # Configure node endpoints for the path from CPU to DDR on
+ # qcom/sm8550.
+ echo chm_apps > src_node
+ echo ebi > dst_node
+
+ # Get path between src_node and dst_node. This is only
+ # necessary after updating the node endpoints.
+ echo 1 > get
+
+ # Set desired BW to 1GBps avg and 2GBps peak.
+ echo 1000000 > avg_bw
+ echo 2000000 > peak_bw
+
+ # Vote for avg_bw and peak_bw on the latest path from "get".
+ # Voting for multiple paths is possible by repeating this
+ # process for different nodes endpoints.
+ echo 1 > commit