Re: [PATCH v2] ARM: dts: imx6dl: disable dma support for spi on i.mx6dl

From: Alexander Holler
Date: Mon Sep 15 2014 - 07:50:42 EST


Am 10.09.2014 07:30, schrieb Robin Gong:
There is one weird data in rxfifo after one full rx/tx transfer
done sometimes. It looks a design issue and hard to workaround
totally, so disable dma functhion here. And will re-enable it
once the root cause found.

Hmm, I experience problems with DMA too but on uart3. I'm using the same
workaround for the uart (I've just commented out the dma entries in the DT).
The problem manifests itself here such, that brcm_patchram_plus hangs while uploading the firmware to a BCM4330 connected at uart3 (reproducible).

So maybe there is a bug in the DMA-engine which not only effects SPI. Or both drivers contain the same error in handling DMA (maybe through c&p).
But that's just specualtion from me, I haven't looked further into that problem.

Regards,

Alexander Holler
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