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-rw-r--r--Documentation/admin-guide/perf/dwc_pcie_pmu.rst94
-rw-r--r--Documentation/admin-guide/perf/imx-ddr.rst45
-rw-r--r--Documentation/admin-guide/perf/index.rst1
3 files changed, 132 insertions, 8 deletions
diff --git a/Documentation/admin-guide/perf/dwc_pcie_pmu.rst b/Documentation/admin-guide/perf/dwc_pcie_pmu.rst
new file mode 100644
index 0000000000..d47cd229d7
--- /dev/null
+++ b/Documentation/admin-guide/perf/dwc_pcie_pmu.rst
@@ -0,0 +1,94 @@
+======================================================================
+Synopsys DesignWare Cores (DWC) PCIe Performance Monitoring Unit (PMU)
+======================================================================
+
+DesignWare Cores (DWC) PCIe PMU
+===============================
+
+The PMU is a PCIe configuration space register block provided by each PCIe Root
+Port in a Vendor-Specific Extended Capability named RAS D.E.S (Debug, Error
+injection, and Statistics).
+
+As the name indicates, the RAS DES capability supports system level
+debugging, AER error injection, and collection of statistics. To facilitate
+collection of statistics, Synopsys DesignWare Cores PCIe controller
+provides the following two features:
+
+- one 64-bit counter for Time Based Analysis (RX/TX data throughput and
+ time spent in each low-power LTSSM state) and
+- one 32-bit counter for Event Counting (error and non-error events for
+ a specified lane)
+
+Note: There is no interrupt for counter overflow.
+
+Time Based Analysis
+-------------------
+
+Using this feature you can obtain information regarding RX/TX data
+throughput and time spent in each low-power LTSSM state by the controller.
+The PMU measures data in two categories:
+
+- Group#0: Percentage of time the controller stays in LTSSM states.
+- Group#1: Amount of data processed (Units of 16 bytes).
+
+Lane Event counters
+-------------------
+
+Using this feature you can obtain Error and Non-Error information in
+specific lane by the controller. The PMU event is selected by all of:
+
+- Group i
+- Event j within the Group i
+- Lane k
+
+Some of the events only exist for specific configurations.
+
+DesignWare Cores (DWC) PCIe PMU Driver
+=======================================
+
+This driver adds PMU devices for each PCIe Root Port named based on the BDF of
+the Root Port. For example,
+
+ 30:03.0 PCI bridge: Device 1ded:8000 (rev 01)
+
+the PMU device name for this Root Port is dwc_rootport_3018.
+
+The DWC PCIe PMU driver registers a perf PMU driver, which provides
+description of available events and configuration options in sysfs, see
+/sys/bus/event_source/devices/dwc_rootport_{bdf}.
+
+The "format" directory describes format of the config fields of the
+perf_event_attr structure. The "events" directory provides configuration
+templates for all documented events. For example,
+"Rx_PCIe_TLP_Data_Payload" is an equivalent of "eventid=0x22,type=0x1".
+
+The "perf list" command shall list the available events from sysfs, e.g.::
+
+ $# perf list | grep dwc_rootport
+ <...>
+ dwc_rootport_3018/Rx_PCIe_TLP_Data_Payload/ [Kernel PMU event]
+ <...>
+ dwc_rootport_3018/rx_memory_read,lane=?/ [Kernel PMU event]
+
+Time Based Analysis Event Usage
+-------------------------------
+
+Example usage of counting PCIe RX TLP data payload (Units of bytes)::
+
+ $# perf stat -a -e dwc_rootport_3018/Rx_PCIe_TLP_Data_Payload/
+
+The average RX/TX bandwidth can be calculated using the following formula:
+
+ PCIe RX Bandwidth = Rx_PCIe_TLP_Data_Payload / Measure_Time_Window
+ PCIe TX Bandwidth = Tx_PCIe_TLP_Data_Payload / Measure_Time_Window
+
+Lane Event Usage
+-------------------------------
+
+Each lane has the same event set and to avoid generating a list of hundreds
+of events, the user need to specify the lane ID explicitly, e.g.::
+
+ $# perf stat -a -e dwc_rootport_3018/rx_memory_read,lane=4/
+
+The driver does not support sampling, therefore "perf record" will not
+work. Per-task (without "-a") perf sessions are not supported.
diff --git a/Documentation/admin-guide/perf/imx-ddr.rst b/Documentation/admin-guide/perf/imx-ddr.rst
index 90926d0fb8..77418ae5a2 100644
--- a/Documentation/admin-guide/perf/imx-ddr.rst
+++ b/Documentation/admin-guide/perf/imx-ddr.rst
@@ -13,8 +13,8 @@ is one register for each counter. Counter 0 is special in that it always counts
interrupt is raised. If any other counter overflows, it continues counting, and
no interrupt is raised.
-The "format" directory describes format of the config (event ID) and config1
-(AXI filtering) fields of the perf_event_attr structure, see /sys/bus/event_source/
+The "format" directory describes format of the config (event ID) and config1/2
+(AXI filter setting) 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/. The "caps" directory describes filter features implemented
@@ -28,12 +28,11 @@ in DDR PMU, see /sys/bus/events_source/devices/imx8_ddr0/caps/.
AXI filtering is only used by CSV modes 0x41 (axid-read) and 0x42 (axid-write)
to count reading or writing matches filter setting. Filter setting is various
from different DRAM controller implementations, which is distinguished by quirks
-in the driver. You also can dump info from userspace, filter in "caps" directory
-indicates whether PMU supports AXI ID filter or not; enhanced_filter indicates
-whether PMU supports enhanced AXI ID filter or not. Value 0 for un-supported, and
-value 1 for supported.
+in the driver. You also can dump info from userspace, "caps" directory show the
+type of AXI filter (filter, enhanced_filter and super_filter). Value 0 for
+un-supported, and value 1 for supported.
-* With DDR_CAP_AXI_ID_FILTER quirk(filter: 1, enhanced_filter: 0).
+* With DDR_CAP_AXI_ID_FILTER quirk(filter: 1, enhanced_filter: 0, super_filter: 0).
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.
@@ -65,7 +64,37 @@ value 1 for supported.
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).
+* With DDR_CAP_AXI_ID_FILTER_ENHANCED quirk(filter: 1, enhanced_filter: 1, super_filter: 0).
This is an extension to the DDR_CAP_AXI_ID_FILTER quirk which permits
counting the number of bytes (as opposed to the number of bursts) from DDR
read and write transactions concurrently with another set of data counters.
+
+* With DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER quirk(filter: 0, enhanced_filter: 0, super_filter: 1).
+ There is a limitation in previous AXI filter, it cannot filter different IDs
+ at the same time as the filter is shared between counters. This quirk is the
+ extension of AXI ID filter. One improvement is that counter 1-3 has their own
+ filter, means that it supports concurrently filter various IDs. Another
+ improvement is that counter 1-3 supports AXI PORT and CHANNEL selection. Support
+ selecting address channel or data channel.
+
+ Filter is defined with 2 configuration registers per counter 1-3.
+ --Counter N MASK COMP register - including AXI_ID and AXI_MASKING.
+ --Counter N MUX CNTL register - including AXI CHANNEL and AXI PORT.
+
+ - 0: address channel
+ - 1: data channel
+
+ PMU in DDR subsystem, only one single port0 exists, so axi_port is reserved
+ which should be 0.
+
+ .. code-block:: bash
+
+ perf stat -a -e imx8_ddr0/axid-read,axi_mask=0xMMMM,axi_id=0xDDDD,axi_channel=0xH/ cmd
+ perf stat -a -e imx8_ddr0/axid-write,axi_mask=0xMMMM,axi_id=0xDDDD,axi_channel=0xH/ cmd
+
+ .. note::
+
+ axi_channel is inverted in userspace, and it will be reverted in driver
+ automatically. So that users do not need specify axi_channel if want to
+ monitor data channel from DDR transactions, since data channel is more
+ meaningful.
diff --git a/Documentation/admin-guide/perf/index.rst b/Documentation/admin-guide/perf/index.rst
index a2e6f2c811..f4a4513c52 100644
--- a/Documentation/admin-guide/perf/index.rst
+++ b/Documentation/admin-guide/perf/index.rst
@@ -19,6 +19,7 @@ Performance monitor support
arm_dsu_pmu
thunderx2-pmu
alibaba_pmu
+ dwc_pcie_pmu
nvidia-pmu
meson-ddr-pmu
cxl