Off-topic: gdma_register_rx_event_callbacks(513): user context not in internal RAM

[JetForMe]

I apologize for the off-topic question, as this doesn't relate directly to this library, but @mrcodetastic you clearly have experience with DMA and dealing with internal RAM issues, and I'm hoping you can help me, as other forums (and google searches and even ChatGPT) I've tried have so far turned up nothing useful.

Context: I wrote some PDM input (audio input) code that was working fine. Then while troubleshooting my ESP32-HUB75-MatrixPanel-DMA/WiFi issues, I noticed that the Arduino IDE was adding include paths for FreeRTOS libraries for other platforms. I solved that by simply removing those libraries from my Arduino setup.

Now, when I run my PDM code, ESP-IDF gives me some errors during setup:

22:21:46.702 -> E (2938) gdma: gdma_register_rx_event_callbacks(513): user context not in internal RAM
22:21:46.702 -> E (2939) i2s_common: i2s_init_dma_intr(809): Register rx callback failed
22:21:46.702 -> E (2939) i2s_pdm: i2s_channel_init_pdm_rx_mode(485): initialize dma interrupt failed
22:21:46.702 -> i2s_channel_init_pdm_rx_mode() failed with 258: ESP_ERR_INVALID_ARG

This is happening in the i2s_channel_init_pdm_rx_mode() call (code here), which is internally setting up some DMA callbacks (this is before my own call to the queue overflow callback). I can't figure out how to get it to put things in the right RAM.

I appreciate any insight you might have.

[mrcodetastic]

Is your callback function definition prefixed with IRAM_ATTR ?

[JetForMe]

Yeah, it's not my callback. It's one down inside I2S (it sets up a callback with GDMA). Turns out, in arduino-esp32 3.1.2 - 3.2.0-rc1, they have GDMA IRAM SAFE set, but not I2S IRAM SAFE, and that causes I2S to allocate its callback context in PSRAM, but GDMA requires it in IRAM. Allegedly will be fixed in RC2 out today.