Documentation: dwc_pcie_pmu: Update bdf to sbdf

Update document to reflect the driver change to use sbdf instead
of bdf alone.

Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
Reviewed-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240816-dwc_pmu_fix-v2-2-198b8ab1077c@quicinc.com
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Krishna chaitanya chundru 2024-08-16 20:47:21 +05:30 committed by Will Deacon
parent e669388537
commit 96a37ec986

View File

@ -46,16 +46,16 @@ 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
This driver adds PMU devices for each PCIe Root Port named based on the SBDF of
the Root Port. For example,
30:03.0 PCI bridge: Device 1ded:8000 (rev 01)
0001:30:03.0 PCI bridge: Device 1ded:8000 (rev 01)
the PMU device name for this Root Port is dwc_rootport_3018.
the PMU device name for this Root Port is dwc_rootport_13018.
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}.
/sys/bus/event_source/devices/dwc_rootport_{sbdf}.
The "format" directory describes format of the config fields of the
perf_event_attr structure. The "events" directory provides configuration
@ -66,16 +66,16 @@ 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_13018/Rx_PCIe_TLP_Data_Payload/ [Kernel PMU event]
<...>
dwc_rootport_3018/rx_memory_read,lane=?/ [Kernel PMU event]
dwc_rootport_13018/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/
$# perf stat -a -e dwc_rootport_13018/Rx_PCIe_TLP_Data_Payload/
The average RX/TX bandwidth can be calculated using the following formula:
@ -88,7 +88,7 @@ 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/
$# perf stat -a -e dwc_rootport_13018/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.