MMC/SD RTEMS driver for MX1 SDHC controller - initial working version

Pavel Pisa ppisa4lists at pikron.com
Mon Dec 12 01:45:12 UTC 2005


Hello all,

I have finally got the beast to work.
You can download code from my homepage

http://cmp.felk.cvut.cz/~pisa/#arm
http://cmp.felk.cvut.cz/~pisa/rtems/rtems-mx1-mmcsd-051212.tar.gz

The archive contains massively modified and cleaned up FreeScale Linux 2.4
MMC/SD driver version ported and integrated to RTEMS system. Driver supports
read/write of MMC and SD cards. The DOS FAT16/FAT32 filesystem can be created
and mounted. The driver works in the CPU data driven mode only (no DMA yet)
and only 1-bit mode is supported for now. The support and keeping
compatibility with MX21 has been considered during functions rewrite as well.

May it be, that there is something missing in the archive. I have tried
to put together required files distributed over our project, but
may it be that I have not purged all dependencies. I have utilized
our logging infrastructure in the driver and our OMK make system
for example, but published code should be mostly independent of these.

I need to enhance driver to support 4-bit mode and DMA in the future.
Should be doable, because my modifications for Linux 2.6 driver
provide stable read support for SD card in the 4-bit DMA mode under
Linux. The write is broken in 2.6 Linux driver on the other hand,
so I hope to get idea, where is problem from RTEMS working code there.

Thanks to Philippe for sending example, which helped with integration
into RTEMS block devices subsystems. Thanks to Jay for CSB336 BSP again.

Best wishes

              Pavel Pisa



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