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docs: perf: Add imx-ddr to documentation index

Sphinx is currently outputting a warning where
the file 'imx-ddr.rst' is not included in the
documentation index. Additionally, the code
highlighting and doc formatting can be slightly
improved.

Signed-off-by: Adam Zerella <adam.zerella@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
5.4-rM2-2.2.x-imx-squashed
Adam Zerella 2019-09-15 18:20:10 +10:00 committed by Joakim Zhang
parent 9869cf739e
commit 3d2d4538b9
2 changed files with 22 additions and 12 deletions

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@ -19,7 +19,9 @@ devices/imx8_ddr0/format/. The "events" directory describes the events types
hardware supported that can be used with perf tool, see /sys/bus/event_source/
devices/imx8_ddr0/events/. The "caps" directory describes filter features implemented
in DDR PMU, see /sys/bus/events_source/devices/imx8_ddr0/caps/.
e.g.::
.. code-block:: bash
perf stat -a -e imx8_ddr0/cycles/ cmd
perf stat -a -e imx8_ddr0/read/,imx8_ddr0/write/ cmd
@ -35,25 +37,32 @@ value 1 for supported.
Filter is defined with two configuration parts:
--AXI_ID defines AxID matching value.
--AXI_MASKING defines which bits of AxID are meaningful for the matching.
0corresponding bit is masked.
1: corresponding bit is not masked, i.e. used to do the matching.
- 0: corresponding bit is masked.
- 1: corresponding bit is not masked, i.e. used to do the matching.
AXI_ID and AXI_MASKING are mapped on DPCR1 register in performance counter.
When non-masked bits are matching corresponding AXI_ID bits then counter is
incremented. Perf counter is incremented if
AxID && AXI_MASKING == AXI_ID && AXI_MASKING
AxID && AXI_MASKING == AXI_ID && AXI_MASKING
This filter doesn't support filter different AXI ID for axid-read and axid-write
event at the same time as this filter is shared between counters.
e.g.::
perf stat -a -e imx8_ddr0/axid-read,axi_mask=0xMMMM,axi_id=0xDDDD/ cmd
perf stat -a -e imx8_ddr0/axid-write,axi_mask=0xMMMM,axi_id=0xDDDD/ cmd
NOTE: axi_mask is inverted in userspace(i.e. set bits are bits to mask), and
it will be reverted in driver automatically. so that the user can just specify
axi_id to monitor a specific id, rather than having to specify axi_mask.
e.g.::
perf stat -a -e imx8_ddr0/axid-read,axi_id=0x12/ cmd, which will monitor ARID=0x12
.. code-block:: bash
perf stat -a -e imx8_ddr0/axid-read,axi_mask=0xMMMM,axi_id=0xDDDD/ cmd
perf stat -a -e imx8_ddr0/axid-write,axi_mask=0xMMMM,axi_id=0xDDDD/ cmd
.. note::
axi_mask is inverted in userspace(i.e. set bits are bits to mask), and
it will be reverted in driver automatically. so that the user can just specify
axi_id to monitor a specific id, rather than having to specify axi_mask.
.. code-block:: bash
perf stat -a -e imx8_ddr0/axid-read,axi_id=0x12/ cmd, which will monitor ARID=0x12
* With DDR_CAP_AXI_ID_FILTER_ENHANCED quirk(filter: 1, enhanced_filter: 1).
This is an extension to the DDR_CAP_AXI_ID_FILTER quirk which permits

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@ -8,6 +8,7 @@ Performance monitor support
:maxdepth: 1
hisi-pmu
imx-ddr
qcom_l2_pmu
qcom_l3_pmu
arm-ccn