commit c9e46ca612cfbb0cf890f7ae7389b742e90efe64 upstream.
The current interconnect provider registration interface is inherently
racy as nodes are not added until the after adding the provider. This
can specifically cause racing DT lookups to trigger a NULL-pointer
deference when either a NULL pointer or not fully initialised node is
returned from exynos_generic_icc_xlate().
Switch to using the new API where the provider is not registered until
after it has been fully initialised.
Fixes: 2f95b9d5cf ("interconnect: Add generic interconnect driver for Exynos SoCs")
Cc: stable@vger.kernel.org # 5.11
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20230306075651.2449-16-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3aab264875bf3c915ea2517fae1eec213e0b4987 upstream.
Make sure to add the newly allocated interconnect node to the provider
before adding the PM QoS request so that the node is freed on errors.
Fixes: 2f95b9d5cf ("interconnect: Add generic interconnect driver for Exynos SoCs")
Cc: stable@vger.kernel.org # 5.11
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20230306075651.2449-15-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds a generic interconnect driver for Exynos SoCs in order
to provide interconnect functionality for each "samsung,exynos-bus"
compatible device.
The SoC topology is a graph (or more specifically, a tree) and its
edges are described by specifying in the 'interconnects' property
the interconnect consumer path for each interconnect provider DT node.
Each bus is now an interconnect provider and an interconnect node as
well (cf. Documentation/interconnect/interconnect.rst), i.e. every bus
registers itself as a node. Node IDs are not hard coded but rather
assigned dynamically at runtime. This approach allows for using this
driver with various Exynos SoCs.
Frequencies requested via the interconnect API for a given node are
propagated to devfreq using dev_pm_qos_update_request(). Please note
that it is not an error when CONFIG_INTERCONNECT is 'n', in which
case all interconnect API functions are no-op.
The samsung,data-clk-ratio DT property is used to specify the ratio
of the interconect bandwidth to the minimum data clock frequency
for each bus.
Due to unspecified relative probing order, -EPROBE_DEFER may be
propagated to ensure that the parent is probed before its children.
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Artur Świgoń <a.swigon@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Link: https://lore.kernel.org/r/20201112140931.31139-3-s.nawrocki@samsung.com
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
