Support PSRAM in DmaTxBuf

[liebman]

Thank you for your contribution!

We appreciate the time and effort you've put into this pull request.
To help us review it efficiently, please ensure you've gone through the following checklist:

Submission Checklist 📝

• I have updated existing examples or added new ones (if applicable).
• I have used cargo xtask fmt-packages command to ensure that all changed code is formatted correctly.
• My changes were added to the CHANGELOG.md in the proper section.
• I have added necessary changes to user code to the Migration Guide.
• My changes are in accordance to the esp-rs API guidelines

Extra:

• I have read the CONTRIBUTING.md guide and followed its instructions.

Pull Request Details 📖

Description

This PR adds support for PSRAM in DmaTxBuf allowing DMA transfers out from PSRAM.

Some observations:

• it seems to only work with octal PSRAM
• there seem to be some edge cases where
  • changing the CHUNK_SIZE makes it work or fail
  • changing the BUFFER_SIZE makes it work or fail

Testing

-The example now works with log (actual issue was my confusion)

• I added a hardware test that fails :-(
• this mostly works on esp32s3 with opsram-8m and one with psram-2m

[bugadani]

(and 100% fails on an esp32s3 with psram-2m)

Lovely, maybe it has something to do with the reduced bandwidth of QSPI vs OSPI?

[liebman]

(and 100% fails on an esp32s3 with psram-2m)

Lovely, maybe it has something to do with the reduced bandwidth of QSPI vs OSPI?

Actually I think it was because one of my modules only has quad psram-2m and I had it configured for opsram-2m

example seems to work now

[Dominaezzz]

There should be a check here to make sure block_size is provided when the buffer is in PSRAM

[liebman]

I tested dma from psram with all of the block sizes and they all worked on octal psram. I think even none worked - that would have used the default register value. But yea - maybe we should force users to be specific.