]> git.ipfire.org Git - thirdparty/kernel/linux.git/commit
arm_mpam: Register and enable IRQs
authorJames Morse <james.morse@arm.com>
Wed, 19 Nov 2025 12:22:51 +0000 (12:22 +0000)
committerCatalin Marinas <catalin.marinas@arm.com>
Wed, 19 Nov 2025 18:34:22 +0000 (18:34 +0000)
commit49aa621c4dcaf8e3cfeb9e73d07a9746b889f9e8
treeef8748bd2f8bf938a6ed01988d82ac13aa93e71c
parent3bd04fe7d807bbdcfe75b29ca82fae4e2d7dc524
arm_mpam: Register and enable IRQs

Register and enable error IRQs. All the MPAM error interrupts indicate a
software bug, e.g. out of range partid. If the error interrupt is ever
signalled, attempt to disable MPAM.

Only the irq handler accesses the MPAMF_ESR register, so no locking is
needed. The work to disable MPAM after an error needs to happen at process
context as it takes mutex. It also unregisters the interrupts, meaning
it can't be done from the threaded part of a threaded interrupt.
Instead, mpam_disable() gets scheduled.

Enabling the IRQs in the MSC may involve cross calling to a CPU that
can access the MSC.

Once the IRQ is requested, the mpam_disable() path can be called
asynchronously, which will walk structures sized by max_partid. Ensure
this size is fixed before the interrupt is requested.

CC: Rohit Mathew <rohit.mathew@arm.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Tested-by: Rohit Mathew <rohit.mathew@arm.com>
Tested-by: Fenghua Yu <fenghuay@nvidia.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com>
Tested-by: Gavin Shan <gshan@redhat.com>
Tested-by: Zeng Heng <zengheng4@huawei.com>
Tested-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
drivers/resctrl/mpam_devices.c
drivers/resctrl/mpam_internal.h