[PATCH] arm: Improve MMC performance on Versatile Express

[Nicolas Pitre]

On Fri, 21 Jan 2011, Pawel Moll wrote:

> VE suffers from serious problem with MMC transfers - low performance,
> errors when other IO peripherals (especially USB) are used at the
> same time etc.
> 
> It all boils down to the MMC controller short FIFO and - in result -
> timing constrains. The most problematic case - USB driver hogging
> CPU and MMC FIFO under/overruns in the result - can be mitigated on
> SMP system by distributing interrupts handling for these peripherals
> between cores.

Wouldn't the ultimate solution be to simply use FIQs to service the MMC FIFO?


Nicolas