On 2019/6/15 9:09, Jeremy Linton wrote:

This patch series enables the Arm Statistical Profiling
Extension (SPE) on ACPI platforms.

This is possible because ACPI 6.3 uses a previously
reserved field in the MADT to store the SPE interrupt
number, similarly to how the normal PMU is described.
If a consistent valid interrupt exists across all the
cores in the system, a platform device is registered.
That then triggers the SPE module, which runs as normal.

We also add the ability to parse the PPTT for IDENTICAL
cores. We then use this to sanity check the single SPE
device we create. This creates a bit of a problem with
respect to the specification though. The specification
says that its legal for multiple tree's to exist in the
PPTT. We handle this fine, but what happens in the
case of multiple tree's is that the lack of a common
node with IDENTICAL set forces us to assume that there
are multiple non-IDENTICAL cores in the machine.

v3->v4: Rebase to 5.2.
	Minor formatting, patch rearrangement.
	Add missing `inline` in static header definition.
	Drop ARM_SPE_ACPI and just use ARM_SPE_PMU.

Tested on top of 5.2-rc1, I can see in the boot log:

arm_spe_pmu arm,spe-v1: probed for CPUs 0-95 [max_record_sz 128, align 4, features 0x7]

and I also tested perf record, and works as expected,

Tested-by: Hanjun Guo <guohanjun@huawei.com>

Thanks
Hanjun


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