Hi, For v2.5 PYNQ during OS boot a bitstream/Overlay is no longer loaded into the PL. But what if I wanted to have it load one? Is there a non-volatile script or service that can be enabled to restore the old (prior to v2.5) behavior? Thank you

There are many ways to do that. Image v2.5 refrains from loading bitstreams because it uses FPGA manager framework and device tree overlay, which does not load bitstream during boot. I think the best practice for users is to have a systemctl service which calls out to customized script, which you c…

Hi Rock, Thanks for the reply. One use case would be to simply power up a design or demo that can start running without any user input. Another related one would be: perhaps there is a mezzanine attached that won’t operate correctly without some PL pins being pulled to the right state and the soo…

I’m using a SnickerdoodleBlack/piSmasher board that uses Peripherals ENET0 and ENET1 with EMIO. The PHY layer connects to the EMIO through Gmii to Rgmii IP. I need the FPGA loaded for U-BOOT to see the ethernet ports so that it can TFTPBOOT images (mostly for testing). Additionally, if the FPGA …

If you really need bitstream to be loaded during boot, like the normal ways, you can comment out line 139,140, and 141 of: Xilinx/PYNQ/blob/master/sdbuild/Makefile#L139 .PHONY: bsp_$1 PL_PROJ_$1 := $$(BUILD_ROOT_$1)/petalinux_project PL…

Hi Rock, Commenting out lines 139-141 of the sdbuild/Makefile did the job. So far I can use the ethernet interfaces in both uboot and Linux without any hanging (though I have not used it a lot yet). I do not know if I really need the bitstream loaded during the first stage boot (only needed that …

I think you have verified the bitstream is working, which is good. I am not quite familiar with that board, but it is possible to just load bitstream as a service (like the boot_leds.service) during OS booting. In that case you don’t have to comment out line 139-141. Also, if your ethernet depends o…

I should be able to figure out how to load the bitstream as a service, but I do not understand what you mean by “along with the device tree segment” ? Is there any documentation on that kind of operation.

Right now there is not, but I can try to add it in next release. If you look at the overlay Python API, you can do something like: ol = Overlay('your_overlay.bit', dtbo="your_overlay.dtb") Then the dtbo file, compiled from dts, can be inserted to your system device tree. After that you can probabl…

For v2.5 is there a way to have it load a bitstream during power-up like it did in prior versions of PYNQ?

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For v2.5 is there a way to have it load a bitstream during power-up like it did in prior versions of PYNQ?

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