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diff --git a/sources/xdma_driver/readme.txt b/sources/xdma_driver/readme.txt new file mode 100644 index 0000000..cbc80f0 --- /dev/null +++ b/sources/xdma_driver/readme.txt @@ -0,0 +1,140 @@ +Modifications to make the dirver compatible with newer Linux kernels: +===================================================================== +For kernel version >= 5.3.0: +- xdma/: + - cdev_ctrl.c: Interface changed for access_ok(): https://forums.xilinx.com/t5/PCIe-and-CPM/PCIe-DMA-driver-compilation-issues-in-Linux-Ubuntu-19-04/td-p/1022239 + + - cdev_xvc.c: + - libxdma.c: Does not need mmiowb() + +(This readme is less relevant as we've modified the file structure) + +The files in this directory provide Xilinx PCIe DMA drivers, example software, +and example test scripts that can be used to exercise the Xilinx PCIe DMA IP. + +This software can be used directly or referenced to create drivers and software +for your Xilinx FPGA hardware design. + +Directory and file description: +=============================== + - xdma/: This directory contains the Xilinx PCIe DMA kernel module + driver files. + + - libxdma/: This directory contains support files for the kernel driver module, + which interfaces directly with the XDMA IP. + + - include/: This directory contains all include files that are needed for + compiling driver. + + - etc/: This directory contains rules for the Xilinx PCIe DMA kernel module + and software. The files in this directory should be copied to the /etc/ + directory on your linux system. + + - tests/: This directory contains example application software to exercise the + provided kernel module driver and Xilinx PCIe DMA IP. This directory + also contains the following scripts and directories. + + - load_driver.sh: + This script loads the kernel module and creates the necissary + kernel nodes used by the provided software. + The The kernel device nodes will be created under /dev/xdma*. + Additional device nodes are created under /dev/xdma/card* to + more easily differentiate between multiple PCIe DMA enabled + cards. Root permissions will be required to run this script. + + - run_test.sh: + This script runs sample tests on a Xilinx PCIe DMA target and + returns a pass (0) or fail (1) result. + This script is intended for use with the PCIe DMA example + design. + + - perform_hwcount.sh: + This script runs hardware performance for XDMA for both Host to + Card (H2C) and Card to Host (C2H). The result are copied to + 'hw_log_h2c.txt' and hw_log_c2h.txt' text files. + For each direction the performance script loops from 64 bytes + to 4MBytes and generate performance numbers (byte size doubles + for each loop count). + You can grep for 'data rate' on those two files to see data + rate values. + Data rate values are in percentage of maximum throughput. + Maximum data rate for x8 Gen3 is 8Gbytes/s, so for a x8Gen3 + design value of 0.81 data rate is 0.81*8 = 6.48Gbytes/s. + Maximum data rate for x16 Gen3 is 16Gbytes/s, so for a x16Gen3 + design value of 0.78 data rate is 0.78*16 = 12.48Gbytes/s. + This program can be run on AXI-MM example design. + AXI-ST example design is a loopback design, both H2C and C2H + are connected. Running on AXI-ST example design will not + generate proper numbers. + If a AXI-ST design is independent of H2C and C2H, performance + number can be generated. + - data/: + This directory contains binary data files that are used for DMA + data transfers to the Xilinx FPGA PCIe endpoint device. + +Usage: + - Change directory to the driver directory. + cd xdma + - Compile and install the kernel module driver. + make install + - Change directory to the tools directory. + cd tools + - Compile the provided example test tools. + make + - Copy the provided driver rules from the etc directory to the /etc/ directory + on your system. + cp ../etc/udev/rules.d/* /etc/udev/rules.d/ + - Load the kernel module driver: + a. modprobe xdma + b. using the provided script. + cd tests + ./load_driver.sh + - Run the provided test script to generate basic DMA traffic. + ./run_test.sh + - Check driver Version number + modinfo xdma (or) + modinfo ../xdma/xdma.ko + +Updates and Backward Compaitiblity: + - The following features were added to the PCIe DMA IP and driver in Vivado + 2016.1. These features cannot be used with PCIe DMA IP if the IP was + generated using a Vivado build earlier than 2016.1. + - Poll Mode: Earlier versions of Vivado only support interrupt mode which + is the default behavior of the driver. + - Source/Destination Address: Earlier versions of Vivado PCIe DMA IP + required the low-order bits of the Source and Destination address to be + the same. + As of 2016.1 this restriction has been removed and the Source and + Destination addresses can be any arbitrary address that is valid for + your system. + +Frequently asked questions: + Q: How do I uninstall the kernel module driver? + A: Use the following commands to uninstall the driver. + - Uninstall the kernel module. + rmmod -s xdma + - Delete the dma rules that were added. + rm -f /etc/udev/rules.d/60-xdma.rules + rm -f /etc/udev/rules.d/xdma-udev-command.sh + + Q: How do I modify the PCIe Device IDs recognized by the kernel module driver? + A: The xdma/xdma_mod.c file constains the pci_device_id struct that identifies + the PCIe Device IDs that are recognized by the driver in the following + format: + { PCI_DEVICE(0x10ee, 0x8038), }, + Add, remove, or modify the PCIe Device IDs in this struct as desired. Then + uninstall the existing xdma kernel module, compile the driver again, and + re-install the driver using the load_driver.sh script. + + Q: By default the driver uses interupts to signal when DMA transfers are + completed. How do I modify the driver to use polling rather than + interrupts to determine when DMA transactions are completed? + A: The driver can be changed from being interrupt driven (default) to being + polling driven (poll mode) when the kernel module is inserted. To do this + modify the load_driver.sh file as follows: + Change: insmod xdma/xdma.ko + To: insmod xdma/xdma.ko poll_mode=1 + Note: Interrupt vs Poll mode will apply to all DMA channels. If desired the + driver can be modified such that some channels are interrupt driven while + others are polling driven. Refer to the poll mode section of PG195 for + additional information on using the PCIe DMA IP in poll mode. |