> -----Original Message-----
> From: John Garry <john.garry@xxxxxxxxxx>
> Sent: 2020年11月30日 17:46
> To: Joakim Zhang <qiangqing.zhang@xxxxxxx>; will@xxxxxxxxxx;
> robh+dt@xxxxxxxxxx
> Cc: devicetree@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>; Frank Li
> <frank.li@xxxxxxx>
> Subject: Re: [PATCH 2/2] perf/imx_ddr: Add system PMU identifier for
> userspace
>
> On 28/11/2020 05:36, Joakim Zhang wrote:
> > The DDR Perf for i.MX8 is a system PMU whose AXI ID would different
> > from SoC to SoC. Need expose system PMU identifier for userspace which
> > refer to /sys/bus/event_source/devices/<PMU DEVICE>/identifier.
> >
> > Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
> > ---
> > drivers/perf/fsl_imx8_ddr_perf.c | 42
> ++++++++++++++++++++++++++++++++
> > 1 file changed, 42 insertions(+)
> >
> > diff --git a/drivers/perf/fsl_imx8_ddr_perf.c
> > b/drivers/perf/fsl_imx8_ddr_perf.c
> > index 4f063fb1c6b4..3517d2fb1469 100644
> > --- a/drivers/perf/fsl_imx8_ddr_perf.c
> > +++ b/drivers/perf/fsl_imx8_ddr_perf.c
> > @@ -50,6 +50,7 @@ static DEFINE_IDA(ddr_ida);
> >
> > struct fsl_ddr_devtype_data {
> > unsigned int quirks; /* quirks needed for different DDR Perf core
> */
> > + const char *identifier; /* system PMU identifier for userspace */
>
> so if this is not set, then what does the sysfs identifier file show?
Seems to be (null).
> It seems to be not set for "fsl,imx8-ddr-pmu" or "fsl,imx8m-ddr-pmu"
> matching.
>
> Maybe it's better do like I did for SMMU PMCG, and not show the file if not set.
OK, I will improve it. Thanks.
Best Regards,
Joakim Zhang
> Thanks,
> John
>
> > };
> >
> > static const struct fsl_ddr_devtype_data imx8_devtype_data; @@
> > -58,13 +59,32 @@ static const struct fsl_ddr_devtype_data
> imx8m_devtype_data = {
> > .quirks = DDR_CAP_AXI_ID_FILTER,
> > };
> >
> > +static const struct fsl_ddr_devtype_data imx8mq_devtype_data = {
> > + .quirks = DDR_CAP_AXI_ID_FILTER,
> > + .identifier = "i.MX8MQ",
> > +};
> > +
> > +static const struct fsl_ddr_devtype_data imx8mm_devtype_data = {
> > + .quirks = DDR_CAP_AXI_ID_FILTER,
> > + .identifier = "i.MX8MM",
> > +};
> > +
> > +static const struct fsl_ddr_devtype_data imx8mn_devtype_data = {
> > + .quirks = DDR_CAP_AXI_ID_FILTER,
> > + .identifier = "i.MX8MN",
> > +};
> > +
> > static const struct fsl_ddr_devtype_data imx8mp_devtype_data = {
> > .quirks = DDR_CAP_AXI_ID_FILTER_ENHANCED,
> > + .identifier = "i.MX8MP",
> > };
> >
> > static const struct of_device_id imx_ddr_pmu_dt_ids[] = {
> > { .compatible = "fsl,imx8-ddr-pmu", .data = &imx8_devtype_data},
> > { .compatible = "fsl,imx8m-ddr-pmu", .data =
> &imx8m_devtype_data},
> > + { .compatible = "fsl,imx8mq-ddr-pmu", .data = &imx8mq_devtype_data},
> > + { .compatible = "fsl,imx8mm-ddr-pmu", .data = &imx8mm_devtype_data},
> > + { .compatible = "fsl,imx8mn-ddr-pmu", .data = &imx8mn_devtype_data},
> > { .compatible = "fsl,imx8mp-ddr-pmu", .data =
> &imx8mp_devtype_data},
> > { /* sentinel */ }
> > };
> > @@ -84,6 +104,27 @@ struct ddr_pmu {
> > int id;
> > };
> >
> > +static ssize_t ddr_perf_identifier_show(struct device *dev,
> > + struct device_attribute *attr,
> > + char *page)
> > +{
> > + struct ddr_pmu *pmu = dev_get_drvdata(dev);
> > +
> > + return sprintf(page, "%s\n", pmu->devtype_data->identifier); }
> > +
> > +static struct device_attribute ddr_perf_identifier_attr =
> > + __ATTR(identifier, 0444, ddr_perf_identifier_show, NULL);
> > +
> > +static struct attribute *ddr_perf_identifier_attrs[] = {
> > + &ddr_perf_identifier_attr.attr,
> > + NULL,
> > +};
> > +
> > +static struct attribute_group ddr_perf_identifier_attr_group = {
> > + .attrs = ddr_perf_identifier_attrs,
> > +};
> > +
> > enum ddr_perf_filter_capabilities {
> > PERF_CAP_AXI_ID_FILTER = 0,
> > PERF_CAP_AXI_ID_FILTER_ENHANCED,
> > @@ -237,6 +278,7 @@ static const struct attribute_group *attr_groups[] = {
> > &ddr_perf_format_attr_group,
> > &ddr_perf_cpumask_attr_group,
> > &ddr_perf_filter_cap_attr_group,
> > + &ddr_perf_identifier_attr_group,
> > NULL,
> > };
> >
> >
