Hi @mithro. I have been trying to get memory-mapped (Q)SPI PSRAM working with LiteX for some time now with no success. I have some working Verilog for QSPI PSRAM in this repo: https://github.com/machdyne/qqspi

If anyone wants to attempt this I can probably provide a 32MB QSPI PSRAM PMOD.

I had this working in https://github.com/xobs/haddecks/blob/master/rtl/spi_ram.py, and I was working on interleaving access in https://github.com/xobs/haddecks/blob/master/rtl/spi_ram_dual.py

There are tests in https://github.com/xobs/haddecks/blob/master/sim/spiram.v

Thanks! This is working for me. I had to use dummy=6 with APS6404L-3SQR-SN PSRAM.

Maybe this can be merged into litex.soc.cores or litespi?

I have noticed a few boards with similar SPI PSRAM and with the QQSPI PMOD it's possible to add 32MB to any board with a PMOD socket, having this capability in LiteX might be useful, especially for the smaller boards.

I sucessfully integrated the PSRAM core from @xobs into a newer version of LiteX by patching the example SoC script, see litex-hub/micropython@d7d2203

I think this is ready to go mainstream. Excellent core! It worked first time

This development makes the PSRAM appear as SPI flash litex-hub/litex-boards@b1df2c0