MMC/SD now works on h2200

I just got MMC/SD working on h2200, starting from the DMA driver from the
S3C2410 port and the opentom MMC/SD driver. I successfully mounted my ancient
8MB MMC card, played an MP3 from it, copied a file to it and verified its
md5dum, and umounted it without error.

As for speed, my lame benchmark ('date; dd if=/dev/mmcblk0 of=/dev/null
bs=16k; date'), I'm getting about 490KB/s. I'm curious how fast SD cards will
be. The driver uses HAMCOP's DMA controller to read the data into HAMCOP's
SRAM, and then memcpy (via dma_unmap_sg()) to its final destination, so it
should be pretty fast. If I'm understanding the PXA/HAMCOP configuration
correctly, it may be possible to use PXA's DMA to copy from SRAM to SDRAM;
would that be worthwhile? I suppose it would free up the processor some.

I hope to commit my patches soon, in the next day or two. (I need to remove a
lot of junk resulting from my flailing about trying to get this working.)

It should work on SAMCOP/h5400 with little modification, and I'm guessing it
will be significantly faster than the 2.4 version.

Many thanks to those who answered so many basic questions, especially pb.

Matt
Received on Sun Apr 24 2005 - 04:15:32 EDT