# How To Allocate PL DDR4 on RFSoC4x2 in PYNQ 3.0.1

**URL:** <https://discuss.pynq.io/t/how-to-allocate-pl-ddr4-on-rfsoc4x2-in-pynq-3-0-1/5586>\
**Category:** Support\
**Created:** [May 16, 2023, 1:34am UTC](https://discuss.pynq.io/t/how-to-allocate-pl-ddr4-on-rfsoc4x2-in-pynq-3-0-1/5586 "2023-05-16T01:34:01Z")\
**Posts on this page:** 1\
**Showing post:** 8

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**Author:** ![Idos](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/idos/32/3887_2.png) [@Idos](https://discuss.pynq.io/u/Idos)\
**Post date:** [May 23, 2023, 8:17am UTC](https://discuss.pynq.io/t/how-to-allocate-pl-ddr4-on-rfsoc4x2-in-pynq-3-0-1/5586/8 "2023-05-23T08:17:04Z")

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![Screenshot 2023-05-23 110428](https://us1.discourse-cdn.com/flex019/uploads/pynq1/original/2X/f/f02375dcf2d36a038d898a94563bad11f056f9f8.jpeg)

Hey Mario @marioruiz

I am not trying to allocate the PL-DDR, however, it seems to fall back on the contiguous memory allocator, nevertheless, xrt.xclAllocBO returns -1, which means it is trying to allocate buffers without success, It derives that the problem is also with the CMA .

I would try and update this dtbo, or even create a new one. The second question which raises is why the CMA fails. am I in the right direction?

Thanks, everyone.

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