Some additional notes from testing last night (more or less blindly after a load of googling for dwc_otg errors and mitigations):
* Adding dwc_otg.speed=1 (limiting the driver speed to Full Speed USB1.1), fixes the mass-storage issue, but breaks compatibility with most keyboards. So, not terribly useful as a work-around but may be helpful in debugging?
* All other attempts either yielded no difference or just broke things further; did have a quick play with the various DMA options (e.g. dma_enable) on the basis of your notes above but managed no improvement.
Some additional notes from testing last night (more or less blindly after a load of googling for dwc_otg errors and mitigations):
* Adding dwc_otg.speed=1 (limiting the driver speed to Full Speed USB1.1), fixes the mass-storage issue, but breaks compatibility with most keyboards. So, not terribly useful as a work-around but may be helpful in debugging?
* All other attempts either yielded no difference or just broke things further; did have a quick play with the various DMA options (e.g. dma_enable) on the basis of your notes above but managed no improvement.