admin-guide/perf/imx-ddr.rst

17 (AXI filter setting) fields of the perf_event_attr structure, see /sys/bus/event_source/
19 hardware supported that can be used with perf tool, see /sys/bus/event_source/
23     .. code-block:: bash
25         perf stat -a -e imx8_ddr0/cycles/ cmd
26         perf stat -a -e imx8_ddr0/read/,imx8_ddr0/write/ cmd
28 AXI filtering is only used by CSV modes 0x41 (axid-read) and 0x42 (axid-write)
31 in the driver. You also can dump info from userspace, "caps" directory show the
32 type of AXI filter (filter, enhanced_filter and super_filter). Value 0 for
33 un-supported, and value 1 for supported.
35 * With DDR_CAP_AXI_ID_FILTER quirk(filter: 1, enhanced_filter: 0, super_filter: 0).
37   --AXI_ID defines AxID matching value.
38   --AXI_MASKING defines which bits of AxID are meaningful for the matching.
40       - 0: corresponding bit is masked.
41       - 1: corresponding bit is not masked, i.e. used to do the matching.
44   When non-masked bits are matching corresponding AXI_ID bits then counter is
49   This filter doesn't support filter different AXI ID for axid-read and axid-write
52   .. code-block:: bash
54       perf stat -a -e imx8_ddr0/axid-read,axi_mask=0xMMMM,axi_id=0xDDDD/ cmd
55       perf stat -a -e imx8_ddr0/axid-write,axi_mask=0xMMMM,axi_id=0xDDDD/ cmd
60       it will be reverted in driver automatically. so that the user can just specify
63   .. code-block:: bash
65         perf stat -a -e imx8_ddr0/axid-read,axi_id=0x12/ cmd, which will monitor ARID=0x12
67 * With DDR_CAP_AXI_ID_FILTER_ENHANCED quirk(filter: 1, enhanced_filter: 1, super_filter: 0).
72 * With DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER quirk(filter: 0, enhanced_filter: 0, super_filter: 1).
73   There is a limitation in previous AXI filter, it cannot filter different IDs
75   extension of AXI ID filter. One improvement is that counter 1-3 has their own
77   improvement is that counter 1-3 supports AXI PORT and CHANNEL selection. Support
80   Filter is defined with 2 configuration registers per counter 1-3.
81   --Counter N MASK COMP register - including AXI_ID and AXI_MASKING.
82   --Counter N MUX CNTL register - including AXI CHANNEL and AXI PORT.
84       - 0: address channel
85       - 1: data channel
90   .. code-block:: bash
92       perf stat -a -e imx8_ddr0/axid-read,axi_mask=0xMMMM,axi_id=0xDDDD,axi_channel=0xH/ cmd
93       perf stat -a -e imx8_ddr0/axid-write,axi_mask=0xMMMM,axi_id=0xDDDD,axi_channel=0xH/ cmd