Documentation: PCI: Add userguide for PCI endpoint test function

Add documentation to help users use pci-epf-test function driver and
pci_endpoint_test host driver for testing PCI.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Kishon Vijay Abraham I 2017-03-27 15:15:18 +05:30 committed by Bjorn Helgaas
parent 62cb0eff82
commit 16263d9e1d
2 changed files with 181 additions and 0 deletions

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@ -18,5 +18,7 @@ endpoint/pci-endpoint-cfs.txt
- guide to use configfs to configure the PCI endpoint function.
endpoint/pci-test-function.txt
- specification of *PCI test* function device.
endpoint/pci-test-howto.txt
- userguide for PCI endpoint test function.
endpoint/function/binding/
- binding documentation for PCI endpoint function

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@ -0,0 +1,179 @@
PCI TEST USERGUIDE
Kishon Vijay Abraham I <kishon@ti.com>
This document is a guide to help users use pci-epf-test function driver
and pci_endpoint_test host driver for testing PCI. The list of steps to
be followed in the host side and EP side is given below.
1. Endpoint Device
1.1 Endpoint Controller Devices
To find the list of endpoint controller devices in the system:
# ls /sys/class/pci_epc/
51000000.pcie_ep
If PCI_ENDPOINT_CONFIGFS is enabled
# ls /sys/kernel/config/pci_ep/controllers
51000000.pcie_ep
1.2 Endpoint Function Drivers
To find the list of endpoint function drivers in the system:
# ls /sys/bus/pci-epf/drivers
pci_epf_test
If PCI_ENDPOINT_CONFIGFS is enabled
# ls /sys/kernel/config/pci_ep/functions
pci_epf_test
1.3 Creating pci-epf-test Device
PCI endpoint function device can be created using the configfs. To create
pci-epf-test device, the following commands can be used
# mount -t configfs none /sys/kernel/config
# cd /sys/kernel/config/pci_ep/
# mkdir functions/pci_epf_test/func1
The "mkdir func1" above creates the pci-epf-test function device that will
be probed by pci_epf_test driver.
The PCI endpoint framework populates the directory with the following
configurable fields.
# ls functions/pci_epf_test/func1
baseclass_code interrupt_pin revid subsys_vendor_id
cache_line_size msi_interrupts subclass_code vendorid
deviceid progif_code subsys_id
The PCI endpoint function driver populates these entries with default values
when the device is bound to the driver. The pci-epf-test driver populates
vendorid with 0xffff and interrupt_pin with 0x0001
# cat functions/pci_epf_test/func1/vendorid
0xffff
# cat functions/pci_epf_test/func1/interrupt_pin
0x0001
1.4 Configuring pci-epf-test Device
The user can configure the pci-epf-test device using configfs entry. In order
to change the vendorid and the number of MSI interrupts used by the function
device, the following commands can be used.
# echo 0x104c > functions/pci_epf_test/func1/vendorid
# echo 0xb500 > functions/pci_epf_test/func1/deviceid
# echo 16 > functions/pci_epf_test/func1/msi_interrupts
1.5 Binding pci-epf-test Device to EP Controller
In order for the endpoint function device to be useful, it has to be bound to
a PCI endpoint controller driver. Use the configfs to bind the function
device to one of the controller driver present in the system.
# ln -s functions/pci_epf_test/func1 controllers/51000000.pcie_ep/
Once the above step is completed, the PCI endpoint is ready to establish a link
with the host.
1.6 Start the Link
In order for the endpoint device to establish a link with the host, the _start_
field should be populated with '1'.
# echo 1 > controllers/51000000.pcie_ep/start
2. RootComplex Device
2.1 lspci Output
Note that the devices listed here correspond to the value populated in 1.4 above
00:00.0 PCI bridge: Texas Instruments Device 8888 (rev 01)
01:00.0 Unassigned class [ff00]: Texas Instruments Device b500
2.2 Using Endpoint Test function Device
pcitest.sh added in tools/pci/ can be used to run all the default PCI endpoint
tests. Before pcitest.sh can be used pcitest.c should be compiled using the
following commands.
cd <kernel-dir>
make headers_install ARCH=arm
arm-linux-gnueabihf-gcc -Iusr/include tools/pci/pcitest.c -o pcitest
cp pcitest <rootfs>/usr/sbin/
cp tools/pci/pcitest.sh <rootfs>
2.2.1 pcitest.sh Output
# ./pcitest.sh
BAR tests
BAR0: OKAY
BAR1: OKAY
BAR2: OKAY
BAR3: OKAY
BAR4: NOT OKAY
BAR5: NOT OKAY
Interrupt tests
LEGACY IRQ: NOT OKAY
MSI1: OKAY
MSI2: OKAY
MSI3: OKAY
MSI4: OKAY
MSI5: OKAY
MSI6: OKAY
MSI7: OKAY
MSI8: OKAY
MSI9: OKAY
MSI10: OKAY
MSI11: OKAY
MSI12: OKAY
MSI13: OKAY
MSI14: OKAY
MSI15: OKAY
MSI16: OKAY
MSI17: NOT OKAY
MSI18: NOT OKAY
MSI19: NOT OKAY
MSI20: NOT OKAY
MSI21: NOT OKAY
MSI22: NOT OKAY
MSI23: NOT OKAY
MSI24: NOT OKAY
MSI25: NOT OKAY
MSI26: NOT OKAY
MSI27: NOT OKAY
MSI28: NOT OKAY
MSI29: NOT OKAY
MSI30: NOT OKAY
MSI31: NOT OKAY
MSI32: NOT OKAY
Read Tests
READ ( 1 bytes): OKAY
READ ( 1024 bytes): OKAY
READ ( 1025 bytes): OKAY
READ (1024000 bytes): OKAY
READ (1024001 bytes): OKAY
Write Tests
WRITE ( 1 bytes): OKAY
WRITE ( 1024 bytes): OKAY
WRITE ( 1025 bytes): OKAY
WRITE (1024000 bytes): OKAY
WRITE (1024001 bytes): OKAY
Copy Tests
COPY ( 1 bytes): OKAY
COPY ( 1024 bytes): OKAY
COPY ( 1025 bytes): OKAY
COPY (1024000 bytes): OKAY
COPY (1024001 bytes): OKAY