The devm_ioremap() function never returns error pointers, it returns a
NULL pointer if there is an error.
Fixes: 4d5a7680f2 ("perf: Add driver for Arm NI-700 interconnect PMU")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/04d6ccc3-6d31-4f0f-ab0f-7a88342cc09a@stanley.mountain
Signed-off-by: Will Deacon <will@kernel.org>
The Arm NI-700 Network-on-Chip Interconnect has a relatively
straightforward design with a hierarchy of voltage, power, and clock
domains, where each clock domain then contains a number of interface
units and a PMU which can monitor events thereon. As such, it begets a
relatively straightforward driver to interface those PMUs with perf.
Even more so than with arm-cmn, users will require detailed knowledge of
the wider system topology in order to meaningfully analyse anything,
since the interconnect itself cannot know what lies beyond the boundary
of each inscrutably-numbered interface. Given that, for now they are
also expected to refer to the NI-700 documentation for the relevant
event IDs to provide as well. An identifier is implemented so we can
come back and add jevents if anyone really wants to.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/9933058d0ab8138c78a61cd6852ea5d5ff48e393.1725470837.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
