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

On Thu, 4 Feb 2021 15:10:32 +0800
Shaokun Zhang [off-list ref] wrote:

Hi Mark,

在 2021/2/3 21:28, Mark Rutland 写道:

quoted

On Wed, Feb 03, 2021 at 03:51:06PM +0800, Shaokun Zhang wrote:  

quoted

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.  

[...]
  

quoted

+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.  

Ok,

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

Yes, target ID.

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[...]
  

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+	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?  

We expose two fields because we support to count the specified target ID
or some target IDs combination, if a single 'tgtid' field, the later scene
is not supported.

Would _min and _max make that clearer perhaps?

Thanks,
Shaokun

quoted

Thanks,
Mark.
.
  

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