This guide is used as an entry point into the Petalinux tool. This demo shows the following:

Transcription

1 Petalinux Design Entry Guide. This guide is used as an entry point into the Petalinux tool. This demo shows the following: How to create a Linux Image for a Zc702 in Petalinux and boot from the SD card How to use the SYSFS to control the LEDs via the Petalinux Console, and User Applications How to add device drivers to the Device-Tree How to debug a simple GPIO application in SDK Demo files: Attached to this demo, there is a petalinux.zip file. This contains: Zc702_files o Zc702_build.tcl o proc_system_wrapper.vhd o ledapp.c o gpioapp.c Zynq - Step 1: Create the HW: Launch Vivado In Vivado, source the Zc702_files/build_zc702.tcl from the TCL command: Note: For the HW requirements for Zynq see page 7 of UG980 1 stephenm@xilinx.com Xilinx

2 Generate the Output Products: 2 stephenm@xilinx.com Xilinx

3 Next, Generate the Bitstream: Note: This is not needed to create the application. Users can export hardware without a bitstream Finally, Export Hardware: File -> Export -> Export Hardware (Include bitstream) This will create a HDF file in the <project_name>.sdk folder Minimise Vivado 3 stephenm@xilinx.com Xilinx

4 Zynq - Step 2: Create the Petalinux Project Launch Petalinux (on GUUP m ) and change directory to the directory where the HDF from steps 1 was written to (<project_name>.sdk) and run the Petalinux command below: petalinux-create --type project --template zynq --name petalinux_test This will create a default template project, which will be modified in the next step to reflect our actual HW project: petalinux-config --get-hw-description -p petalinux_test The resulting pop up box, in the Subsytem AUTO Hardware Settings will contain all the options based upon the XML file for your Hardware System. We shall be booting from the SD Card. In subsystem AUTO Hardware Settings Advanced Bootable images storage Settings. Select Y to include this: 4 stephenm@xilinx.com Xilinx

5 Then Select to enter the Advanced bootable image storage settings, and select boot image settings, as shown below: Select image storage media, as shown below: Set this to primary sd, as shown below: 5 stephenm@xilinx.com Xilinx

6 Repeat this for the kernel image settings: Save, and Exit to compile 6 stephenm@xilinx.com Xilinx

7 To see the rootfs configuration menu run the command below from the project root cd petalinux_test petalinux-config c rootfs If debugging from SDK is required, a TCF agent will need to be running on the ZC702 board. To add the TCF agent, go to Filesystem Packages base tcf-agent and Y to add this: Save, and Exit to compile 7 stephenm@xilinx.com Xilinx

8 To see the kernel configuration menu run the command below from the project root: cd petalinux_test petalinux-config c kernel Here, we shall enable the following device drivers: GPIO Support o Xilinx GPIO support o Xilinx Zynq GPIO Support LED Support o LED Class Support o LED Support for GPIO connected LEDs o LED Trigger support all triggers Input device support o Keyboards GPIO Buttons Polled GPIO buttons Save, and Exit to compile 8 stephenm@xilinx.com Xilinx

9 Finally, when we are happy with the configuration, we can build the image: petalinux-build We want to boot from the SD card, Next, we can create the boot image. petalinux-package --boot --fsbl images/linux/zynq_fsbl.elf fpga../proc_system_wrapper_hw_platform/proc_system_wrapper.bit --uboot The two files of note here are: BOOT.BIN Images/linux/image.ub 9 stephenm@xilinx.com Xilinx

10 ZC702 Step 3: Booting Linux: Copy both the files below on the SD Card: BOOT.BIN Images/linux/image.ub Place the SD card in the SD slot on the board, insert the USB UART, and the PHY cable and set the Mode pins to M1:5 = and power on the board. 10 stephenm@xilinx.com Xilinx

11 Open a Tera Term, and set the BAUD Rate to : Finally, press the POR_B button on the board and monitor the Tera Term: The login, and password is root 11 stephenm@xilinx.com Xilinx

12 ZC702 Step 4: Access AXI GPIO from Linux User Space Next we will attempt to turn on the LED on the ZC702 via the GPIO. In the Petalinux, the GPIO SYSFS is mounted by default. This interface allows us to access the GPIO pins easily. To see a list of the GPIO pins, type ls /sys/class/gpio from the root (to get to the root type cd ~ ): root@petalinux_test:~# ls /sys/class/gpio export gpiochip0 gpiochip252 unexport So, here gpiochip252 is the base pin. Since we are using a 5 bit GPIO, the range of pins are 252:256. To use a pin, the user will need to checkout this pin so it cannot be used by any other processes on the kernel. This is done by using the export. For example: echo 252 > /sys/class/gpio/export Now, we can set the direction of the pin. This can be either in, or out. For example: echo out > /sys/class/gpio/gpio252/direction Next, we can set the value of the pin. This can either be 1, or 0. For example: echo 1 > /sys/class/gpio/gpio252/value You should see the DS15 LED turn on. Finally, we must check back the pin. This is so other processes can use it. For example: echo 252 > /sys/class/gpio/unexport 12 stephenm@xilinx.com Xilinx

13 With this in mind, we can create a software application based on the information we learned before. We can use Petalinux to create a new C Application: cd petalinux_test petalinux-create --type apps --template c --name gpioapp Enable the app in the rootfs: petalinux-config -c rootfs Select Apps, and select Y for the newly created gpioapp Save, and Exit to compile. This will create, a C template at: petalinux_test\components\apps\gpioapp Copy the code in Zc702_files/gpio_test.c into gpioapp.c. This code replicates what we did in the last step in a C application. This toggles the LED. To build the image into an existing image, use the command below: cd petalinux_test petalinux-build -c rootfs/gpioapp petalinux-build -x package Update the image.ub on the SD card with the newly created image.ub in Images/linux/image.ub and press the POR_B push button on the ZC202 to reboot. 13 stephenm@xilinx.com Xilinx

14 To run the gpioapp, run the command below on the Petalinux console: gpioapp Press Ctrl+c to exit. 14 Xilinx

15 ZC702 Step 5: Access AXI GPIO using device drivers In this section we will be updating the device-tree to include device nodes for the LED, and GPIO Key s. The device-tree files can be found at: petalinux_test\subsystems\linux\configs\device-tree The device-tree structure for these files is as follows: system-top.dts o system-conf.dtsi pl.dtsi ps.dtsi It is not recommended to update the dtsi files directly. So, we can create our own dtsi file, and add it to the device-tree structure. Create a led_nodes.dtsi file and place this into the device-tree structure by adding this as an include into system-top.dts as shown below: So, we should now have: system-top.dts o system-conf.dtsi o led_nodes.dtsi pl.dtsi ps.dtsi 15 stephenm@xilinx.com Xilinx

16 Open the led_nodes.dtsi file, and populate this as shown below: Make sure that the properties are set correctly. All this information can be obtained from leds_gpio.txt, gpio-xilinx.txt and gpio-keys.txt: For example, for the LED compatibility: Required properties: - compatible : should be "gpio-leds". The string < gpios = <&axi_gpio_0 0 0>, &axi_gpio_0 refers to the GPIO name given in the pl.dtsi, and states that led-ds15 is on pin 0, and that the device is active low. Dual channel GPIO controller with configurable number of pins (from 1 to 32 per channel). Every pin can be configured as input/output/tristate. Once the device-tree is updated, the image needs to be rebuilt: cd petalinux_test petalinux-build 16 stephenm@xilinx.com Xilinx

17 We can also verify that the device-tree has been updated correctly using the command below: cd petalinux_test/images/linux../../build/linux/kernel/xlnx-3.14/scripts/dtc/dtc -I dtb -O dts -o system.dts system.dtb This will create a system.dts in the petalinux_test/images/linux folder. You should see the two driver nodes under the AXI Interconnect. When you are happy with the changes, copy the image.ub onto the SD card. Next, Plug the SD card back into the ZC702, and press the POR_B pushbutton. Let the Linux boot, and enter the login (root), and password (login). The LED at DS15 should be beating. To test the GPIO-KEYS, type the command below onto the Petalinux console: cat /dev/input/event0 hexdata Then press SW13, or SW14: 17 stephenm@xilinx.com Xilinx

18 ZC702 Step 6: Using SDK to debug Linux Applications Now that we have the hardware built, the Linux system build, and our drivers added, we can now create some applications in Linux using the SDK tool. In Step 2, we added the TCF agent in the Kernel. We shall be connecting to this TCF agent via the Ethernet port. So, first we need to set up the LAN between our local machine, and the board. To set up the LAN connect the PHY cable into your local machine and go to Start Control Panel Network and Internet Network and Sharing Center: Then select Change adapter settings: 18 Xilinx

19 Right Click on Local Area Connection, and select properties: Select Internet Protocol Version 4 (TCP/IPv4), and select Properties: Use the IP address: , and the Subnet mask Note: When this tutorial is over, and you are wondering why you have no internet connect. This is why. Change it back to Obtain an IP address automatically. 19 stephenm@xilinx.com Xilinx

20 Next, we need to assign an IP address to the board, in the Petalinux console use the command below: Ifconfig eth netmask To test the connection, send a ping to your local machine using the command below on the Petalinux console: Ping Press Ctrl+c to stop the ping 20 stephenm@xilinx.com Xilinx

21 Next, we can launch SDK (locally) and create a workspace. The select new Application Project. Name the app gpio_test, and for the Hardware Platform, Select New: 21 stephenm@xilinx.com Xilinx

22 Browse for your HDF file that you used when exporting from Vivado in Step 1: Select Finish. Note: We technically do not need to build the HW Platform, as this is built already in Linux. 22 Xilinx

23 Then for OS Platform, selecting Linux and Next to continue: 23 Xilinx

24 Select Linux Empty Application, and Finish to Continue: 24 Xilinx

25 In the Project Explorer, right click on the gpio_test/src and select New Source File: 25 Xilinx

26 Name that source file gpio_test.c, and finish to continue: Copy the code in Zc702_files/ledapp.c into src/gpio_test.c. This code uses the led-gpio and gpio-keys drivers to allow the user to control the LED from the pushbuttons. When you build the application is SDK (Project Build All), you will see an error: 'Building target: gpio_test.elf' 'Invoking: ARM Linux gcc linker' arm-xilinx-linux-gnueabi-gcc -o "gpio_test.elf"./src/gpio_test.o./src/gpio_test.o: In function `main': C:\Cases\Projects\petalinux\test_ws\gpio_test\Debug/../src/gpio_test.c:60: undefined reference to `pthread_create' collect2.exe: error: ld returned 1 exit status make: *** [gpio_test.elf] Error 1 26 stephenm@xilinx.com Xilinx

27 This is due to a missing linker flag -lphread. To add this, right click on the gpio_test in Project explorer, and select C/C++ Build Properties. Under ARM Linux gcc linker Inferred Options Software Platform. Select the Ad symbol, and add the lphread option. Select Apply, and OK to Exit. Note: This can be added to the MAKEFILE if creating a Petalinux Application 27 stephenm@xilinx.com Xilinx

28 Next, set up the Target connection. Select the icon highlighted below: Give the target the name zc702 and enter the IP address and the port number as shown below: 28 Xilinx

29 Next, right click on the hello application and select Debug As Debug Configurations: Create a new Debug Configuration (by double clicking on the Xilinx C/C++ application System Debugger). For Debug Type, select Linux Application Debug. For Connection, select the target connection we created previously (zc702). Select Apply and Debug to proceed: 29 stephenm@xilinx.com Xilinx

30 In the Application tab, browse to the gpio_test project. In the Remote File Path, enter /tmp/gpio_test.elf : Select Apply and Debug to continue. 30 stephenm@xilinx.com Xilinx

31 You can either step through the application, or run it all using the debug options seen below: To test, you should see DS15 beating, you can control the speed of the blinking via the SW13, and SW14 push-buttons. You will also see the speed displayed on the serial port in SDK: Note: on the Petalinux console, you can also run the application by using the command below: /tmp/gpio_test.elf 31 Xilinx