[PATCH v2 6/8] drivers/perf: hisi: Add support for HiSilicon SLLC PMU driver

[Mark Rutland]

On Wed, Feb 03, 2021 at 03:51:06PM +0800, Shaokun Zhang wrote:
> HiSilicon's Hip09 is comprised by multi-dies that can be connected by SLLC
> module (Skyros Link Layer Controller), its has separate PMU registers which
> the driver can program it freely and interrupt is supported to handle
> counter overflow. Let's support its driver under the framework of HiSilicon
> uncore PMU driver.

[...]

> +HISI_PMU_EVENT_ATTR_EXTRACTOR(tgtid_lo, config1, 10, 0);
> +HISI_PMU_EVENT_ATTR_EXTRACTOR(tgtid_hi, config1, 21, 11);
> +HISI_PMU_EVENT_ATTR_EXTRACTOR(srcid_cmd, config1, 32, 22);
> +HISI_PMU_EVENT_ATTR_EXTRACTOR(srcid_msk, config1, 43, 33);
> +HISI_PMU_EVENT_ATTR_EXTRACTOR(tracetag_en, config1, 44, 44);

If you could describe these fields in the commit message that would be
helpful.

What is a 'tgtid'? Is that a 'target ID' or something to that effect?

[...]

> +	HISI_PMU_FORMAT_ATTR(tgtid_low, "config1:0-10"),
> +	HISI_PMU_FORMAT_ATTR(tgtid_high, "config1:11-21"),

Does this need to be exposed to userspace in two halves, rather than
being a single 'tgtid' field that the driver can decompose as necessary?

Thanks,
Mark.