Now that the larger counter sizes are probed, make use of them.
Callers of mpam_msmon_read() may not know (or care!) about the different
counter sizes. Allow them to specify mpam_feat_msmon_mbwu and have the
driver pick the counter to use.
Only 32bit accesses to the MSC are required to be supported by the
spec, but these registers are 64bits. The lower half may overflow
into the higher half between two 32bit reads. To avoid this, use
a helper that reads the top half multiple times to check for overflow.
Signed-off-by: Rohit Mathew <rohit.mathew@arm.com>
[morse: merged multiple patches from Rohit, added explicit counter selection ]
Signed-off-by: James Morse <james.morse@arm.com>
Cc: Peter Newman <peternewman@google.com>
Reviewed-by: Ben Horgan <ben.horgan@arm.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Fenghua Yu <fenghuay@nvidia.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.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: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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>
When a CPU comes online, it may bring a newly accessible MSC with
it. Only the default partid has its value reset by hardware, and
even then the MSC might not have been reset since its config was
previously dirtied. e.g. Kexec.
Any in-use partid must have its configuration restored, or reset.
In-use partids may be held in caches and evicted later.
MSC are also reset when CPUs are taken offline to cover cases where
firmware doesn't reset the MSC over reboot using UEFI, or kexec
where there is no firmware involvement.
If the configuration for a RIS has not been touched since it was
brought online, it does not need resetting again.
To reset, write the maximum values for all discovered controls.
CC: Rohit Mathew <Rohit.Mathew@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Gavin Shan <gshan@redhat.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: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The MSC MON_SEL register needs to be accessed from hardirq for the overflow
interrupt, and when taking an IPI to access these registers on platforms
where MSC are not accessible from every CPU. This makes an irqsave
spinlock the obvious lock to protect these registers. On systems with SCMI
or PCC mailboxes it must be able to sleep, meaning a mutex must be used.
The SCMI or PCC platforms can't support an overflow interrupt, and
can't access the registers from hardirq context.
Clearly these two can't exist for one MSC at the same time.
Add helpers for the MON_SEL locking. For now, use a irqsave spinlock and
only support 'real' MMIO platforms.
In the future this lock will be split in two allowing SCMI/PCC platforms
to take a mutex. Because there are contexts where the SCMI/PCC platforms
can't make an access, mpam_mon_sel_lock() needs to be able to fail. Do
this now, so that all the error handling on these paths is present. This
allows the relevant paths to fail if they are needed on a platform where
this isn't possible, instead of having to make explicit checks of the
interface type.
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: 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>
CPUs can generate traffic with a range of PARTID and PMG values,
but each MSC may also have its own maximum size for these fields.
Before MPAM can be used, the driver needs to probe each RIS on
each MSC, to find the system-wide smallest value that can be used.
The limits from requestors (e.g. CPUs) also need taking into account.
While doing this, RIS entries that firmware didn't describe are created
under MPAM_CLASS_UNKNOWN.
This adds the low level MSC write accessors.
While we're here, implement the mpam_register_requestor() call
for the arch code to register the CPU limits. Future callers of this
will tell us about the SMMU and ITS.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Ben Horgan <ben.horgan@arm.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: 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: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Because an MSC can only by accessed from the CPUs in its cpu-affinity
set we need to be running on one of those CPUs to probe the MSC
hardware.
Do this work in the cpuhp callback. Probing the hardware will only
happen before MPAM is enabled, walk all the MSCs and probe those we can
reach that haven't already been probed as each CPU's online call is made.
This adds the low-level MSC register read accessors.
Once all MSCs reported by the firmware have been probed from a CPU in
their respective cpu-affinity set, the probe-time cpuhp callbacks are
replaced. The replacement callbacks will ultimately need to handle
save/restore of the runtime MSC state across power transitions, but for
now there is nothing to do in them: so do nothing.
The architecture's context switch code will be enabled by a static-key,
this can be set by mpam_enable(), but must be done from process context,
not a cpuhp callback because both take the cpuhp lock.
Whenever a new MSC has been probed, the mpam_enable() work is scheduled
to test if all the MSCs have been probed. If probing fails, mpam_disable()
is scheduled to unregister the cpuhp callbacks and free memory.
CC: Lecopzer Chen <lecopzerc@nvidia.com>
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Ben Horgan <ben.horgan@arm.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.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: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
An MSC is a container of resources, each identified by their RIS index.
Some RIS are described by firmware to provide their position in the system.
Others are discovered when the driver probes the hardware.
To configure a resource it needs to be found by its class, e.g. 'L2'.
There are two kinds of grouping, a class is a set of components, which
are visible to user-space as there are likely to be multiple instances
of the L2 cache. (e.g. one per cluster or package)
Add support for creating and destroying structures to allow a hierarchy
of resources to be created.
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.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>
