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

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Thu, 4 Feb 2021 15:10:32 +0800
Shaokun Zhang <zhangshaokun@hisilicon.com> wrote:

> Hi Mark,
> 
> 在 2021/2/3 21:28, Mark Rutland 写道:
> > 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.  
> 
> Ok,
> 
> > 
> > What is a 'tgtid'? Is that a 'target ID' or something to that effect?  
> 
> Yes, target ID.
> 
> > 
> > [...]
> >   
> >> +	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
> 
> > 
> > Thanks,
> > Mark.
> > .
> >   


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