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* interconnect: Add debugfs test clientMike Tipton2023-08-221-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's often useful during test, debug, and development to issue path votes from shell. Add a debugfs client for this purpose. 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 Allowing userspace to directly enable and set bus rates can be dangerous So, following in the footsteps of the regmap [0] and clk [1] frameworks, keep these userspace controls compile-time disabled without Kconfig options to enable them. Enabling this will require code changes to define INTERCONNECT_ALLOW_WRITE_DEBUGFS. [0] commit 09c6ecd39410 ("regmap: Add support for writing to regmap registers via debugfs") [1] commit 37215da5553e ("clk: Add support for setting clk_rate via debugfs") Signed-off-by: Mike Tipton <quic_mdtipton@quicinc.com> Link: https://lore.kernel.org/r/20230807142914.12480-4-quic_mdtipton@quicinc.com Signed-off-by: Georgi Djakov <djakov@kernel.org>
* interconnect: Add interconnect_graph file to debugfsLeonard Crestez2019-12-161-0/+22
| | | | | | | | | | | | | | | | | | | The interconnect graphs can be difficult to understand and the current "interconnect_summary" file doesn't even display links in any way. Add a new "interconnect_graph" file to debugfs in the graphviz "dot" format which describes interconnect providers, nodes and links. The file is human-readable and can be visualized by piping through graphviz. Example: ssh $TARGET cat /sys/kernel/debug/interconnect/interconnect_graph \ | dot -Tsvg > interconnect_graph.svg Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
* docs: driver-api: make interconnect title quieterLouis Taylor2019-11-071-1/+1
| | | | | | | | This makes it consistent with the other headings in the Linux driver implementer's API guide. Signed-off-by: Louis Taylor <louis@kragniz.eu> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* docs: interconnect.rst: add it to the driver-api guideMauro Carvalho Chehab2019-07-151-0/+93
This is intended for Kernel hackers audience. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Reviewed-by: Georgi Djakov <georgi.djakov@linaro.org>