Hello, I have some limitations when using a DMA on a ZCU111. I can’t allocate all the memory I need in my buffers when I use “allocate” function. After some research, I find this : " This buffer is allocated inside the kernel space using xlnk driver. The maximum allocatable memory is defined at ke…

I forgot to specify : I try to build a new image ( PYNQ SD Card — Python productivity for Zynq (Pynq) ), but I don’t find any parameters to modify to increase this maximum allocatable memory. Thanks :slight_smile: Damien

Check under Petalinux Kernel Config. There was a tutorial here a while ago by Peter showing how to port to a new board. If I recall correctly is under the same settings as DMA APF. Device Drivers->Generic Driver Options->Size in Mega Bytes(1024) Device Drivers->Staging drivers (ON)->Xilinx APF Acc…

Hi :slight_smile: Thank you so much for your answers You’re talking about this guide : Deploying PYNQ and Jupyter with Petalinux ? Damien

Hello again. I’m testing the guide, and it’s probably going to work. Nevertheless, I lost the current configuration of ZCU111 v2.5, myrootfs… :frowning: Do you know if I can: just copy the new build kernel to my ZCU111 SD card? or maybe just specify the kernel option when I use this guide: PYNQ…

Hello, I found a “temporary” solution. You need to follow this guide : PYNQ SD Card — Python productivity for Zynq (Pynq) and launch the kernel compilation. In an other terminal look for kernel configuration file and stop the compilation. Edit the file and start again the compilation. WHen It’s fi…

After you have the boot_files built (run make boot_files or run make), the petalinux_project folder should appear in your sdbuild/build/ folder, you can go inside and run petalinux-config -c kernel.

I’m having similar issues with the ZC702 board. For once I can’t set CMA to anything higher than 256MB when building petalinux and even when setting CMA to 256MB I still can only allocate 128MB with ‘allocate’. I’ve used pynq_z1_v2.6.0 to build the SD image and then swapped the BOOT.BIN, boot.scr a…

I do not have any idea, but your comments shed light on my issue. Thanks!

I decided to run this down after working on https://discuss.pynq.io/t/how-to-allocate-pl-ddr4-on-rfsoc4x2-in-pynq-3-0-1/5586/8 given that they’re notionally related. This patch Add hook for EmbeddedDevice XRT devices to allow moving the PSDDR memory region by ld-cd · Pull Request #1424 · Xilinx/PYN…

Pynq & maximum allocatable memory (CMA)

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dimiter August 4, 2020, 9:44am 5

Yep, that’s it.

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Pynq & maximum allocatable memory (CMA)

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