[PATCH] docs: admin-guide/perf: fix imx-ddr.rst warnings

From: Randy Dunlap
Date: Sun Oct 20 2019 - 22:22:01 EST


From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

Fix Sphinx warnings in imx-ddr.rst:

Documentation/admin-guide/perf/imx-ddr.rst:21: WARNING: Unexpected indentation.
Documentation/admin-guide/perf/imx-ddr.rst:34: WARNING: Unexpected indentation.
Documentation/admin-guide/perf/imx-ddr.rst:40: WARNING: Unexpected indentation.
Documentation/admin-guide/perf/imx-ddr.rst:45: WARNING: Unexpected indentation.
Documentation/admin-guide/perf/imx-ddr.rst:52: WARNING: Unexpected indentation.

Fixes: 3724e186fead ("docs/perf: Add documentation for the i.MX8 DDR PMU")
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Joakim Zhang <qiangqing.zhang@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
---
Documentation/admin-guide/perf/imx-ddr.rst | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

--- lnx-54-rc4.orig/Documentation/admin-guide/perf/imx-ddr.rst
+++ lnx-54-rc4/Documentation/admin-guide/perf/imx-ddr.rst
@@ -17,8 +17,8 @@ The "format" directory describes format
(AXI filtering) fields of the perf_event_attr structure, see /sys/bus/event_source/
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/.
- e.g.::
+devices/imx8_ddr0/events/. E.g.::
+
perf stat -a -e imx8_ddr0/cycles/ cmd
perf stat -a -e imx8_ddr0/read/,imx8_ddr0/write/ cmd

@@ -31,22 +31,25 @@ in the driver.
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.
+
0ïcorresponding 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

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.::
+ 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.::
+ E.g.::
+
perf stat -a -e imx8_ddr0/axid-read,axi_id=0x12/ cmd, which will monitor ARID=0x12