linux-stable.git/drivers/interconnect/core.c, branch linux-5.4.y

interconnect: Treat xlate() returning NULL node as an error

2024-01-08T10:29:45+00:00

[ Upstream commit ad2ab1297d0c80899125a842bb7a078abfe1e6ce ]

Currently, if provider->xlate() or provider->xlate_extended()
"successfully" return a NULL node, then of_icc_get_from_provider() won't
consider that an error and will successfully return the NULL node. This
bypasses error handling in of_icc_get_by_index() and leads to NULL
dereferences in path_find().

This could be avoided by ensuring provider callbacks always return an
error for NULL nodes, but it's better to explicitly protect against this
in the common framework.

Fixes: 87e3031b6fbd ("interconnect: Allow endpoints translation via DT")
Signed-off-by: Mike Tipton 
Link: https://lore.kernel.org/r/20231025145829.11603-1-quic_mdtipton@quicinc.com
Signed-off-by: Georgi Djakov 
Signed-off-by: Sasha Levin

interconnect: Do not skip aggregation for disabled paths

2023-08-30T14:27:27+00:00

commit 91b44981a2316e7b00574d32dec4fae356444dcf upstream.

When an interconnect path is being disabled, currently we don't aggregate
the requests for it afterwards. But the re-aggregation step shouldn't be
skipped, as it may leave the nodes with outdated bandwidth data. This
outdated data may actually keep the path still enabled and prevent the
device from going into lower power states.

Reported-by: Atul Dhudase 
Fixes: 7d374b209083 ("interconnect: Add helpers for enabling/disabling a path")
Reviewed-by: Sibi Sankar 
Tested-by: Atul Dhudase 
Reviewed-by: Atul Dhudase 
Link: https://lore.kernel.org/r/20200721120740.3436-1-georgi.djakov@linaro.org
Signed-off-by: Georgi Djakov 
Link: https://lore.kernel.org/r/20200723083735.5616-2-georgi.djakov@linaro.org
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

interconnect: Add helpers for enabling/disabling a path

2023-08-30T14:27:13+00:00

[ Upstream commit 7d374b20908338c9fbb03ea8022a11f3b3e0e55f ]

There is a repeated pattern in multiple drivers where they want to switch
the bandwidth between zero and some other value. This is happening often
in the suspend/resume callbacks. Let's add helper functions to enable and
disable the path, so that callers don't have to take care of remembering
the bandwidth values and handle this in the framework instead.

With this patch the users can call icc_disable() and icc_enable() to lower
their bandwidth request to zero and then restore it back to it's previous
value.

Suggested-by: Evan Green 
Suggested-by: Bjorn Andersson 
Signed-off-by: Georgi Djakov 
Reviewed-by: Matthias Kaehlcke 
Link: https://lore.kernel.org/r/20200507120846.8354-1-georgi.djakov@linaro.org
Signed-off-by: Georgi Djakov 
Stable-dep-of: d2d69354226d ("USB: dwc3: qcom: fix NULL-deref on suspend")
Signed-off-by: Sasha Levin

interconnect: Move internal structs into a separate file

2023-08-30T14:27:13+00:00

[ Upstream commit dd018a9cf9108f9c7d924f6fe09aed745e78a67e ]

Move the interconnect framework internal structs into a separate file,
so that it can be included and used by ftrace code. This will allow us
to expose some more useful information in the traces.

Reviewed-by: Bjorn Andersson 
Signed-off-by: Georgi Djakov 
Stable-dep-of: d2d69354226d ("USB: dwc3: qcom: fix NULL-deref on suspend")
Signed-off-by: Sasha Levin

interconnect: fix mem leak when freeing nodes

2023-03-22T12:28:08+00:00

commit a5904f415e1af72fa8fe6665aa4f554dc2099a95 upstream.

The node link array is allocated when adding links to a node but is not
deallocated when nodes are destroyed.

Fixes: 11f1ceca7031 ("interconnect: Add generic on-chip interconnect API")
Cc: stable@vger.kernel.org      # 5.1
Reviewed-by: Konrad Dybcio 
Signed-off-by: Johan Hovold 
Tested-by: Luca Ceresoli  # i.MX8MP MSC SM2-MB-EP1 Board
Link: https://lore.kernel.org/r/20230306075651.2449-2-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov 
Signed-off-by: Greg Kroah-Hartman

interconnect: core: fix error return code of icc_link_destroy()

2021-04-16T09:46:37+00:00

[ Upstream commit 715ea61532e731c62392221238906704e63d75b6 ]

When krealloc() fails and new is NULL, no error return code of
icc_link_destroy() is assigned.
To fix this bug, ret is assigned with -ENOMEM hen new is NULL.

Reported-by: TOTE Robot 
Signed-off-by: Jia-Ju Bai 
Link: https://lore.kernel.org/r/20210306132857.17020-1-baijiaju1990@gmail.com
Signed-off-by: Georgi Djakov 
Signed-off-by: Sasha Levin

interconnect: Add locking in icc_set_tag()

2019-10-20T09:14:41+00:00

We must ensure that the tag is not changed while we aggregate the
requests. Currently the icc_set_tag() is not using any locks and this
may cause the values to be aggregated incorrectly. Fix this by acquiring
the icc_lock while we set the tag.

Link: https://lore.kernel.org/lkml/20191018141750.17032-1-georgi.djakov@linaro.org/
Fixes: 127ab2cc5f19 ("interconnect: Add support for path tags")
Reviewed-by: Bjorn Andersson 
Signed-off-by: Georgi Djakov

interconnect: Add pre_aggregate() callback

2019-08-13T20:02:48+00:00

Introduce an optional callback in interconnect provider drivers. It can be
used for implementing actions, that need to be executed before the actual
aggregation of the bandwidth requests has started.

The benefit of this for now is that it will significantly simplify the code
in provider drivers.

Suggested-by: Evan Green 
Reviewed-by: Evan Green 
Signed-off-by: Georgi Djakov

interconnect: Add support for path tags

2019-08-13T20:02:44+00:00

Consumers may have use cases with different bandwidth requirements based
on the system or driver state. The consumer driver can append a specific
tag to the path and pass this information to the interconnect platform
driver to do the aggregation based on this state.

Introduce icc_set_tag() function that will allow the consumers to append
an optional tag to each path. The aggregation of these tagged paths is
platform specific.

Reviewed-by: Evan Green 
Signed-off-by: Georgi Djakov

interconnect: convert to DEFINE_SHOW_ATTRIBUTE

2019-04-06T15:03:03+00:00

Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.

Signed-off-by: Yangtao Li 
Signed-off-by: Georgi Djakov