Chris Wood

The ins and outs of booting Linux from SD card

Discussion created by Chris Wood on Jun 3, 2010
Latest reply on Jan 23, 2011 by Benny Kukoy
I thought I would share this little pearl with all you avid i.MX233 developers out there. Getting the i.MX233 to boot from SD card had us running around for a bit. After some effort confirming that the hardware signals were all ok on our target board, Freescale tech support filled us in on the information we needed to get this to happen (which was buried in an errata sheet).

1. There is a bug in the i.MX233 ROM code that causes it to timeout waiting for SD cards that take longer than 4 ms to start up. So under advisement we bought a handful off different SD cards from various vendors and tested each one till we found one that worked. In case you're wondering we found that the SanDisk Qmicro 2GB cards work.

2. By default the fuse bit in the i.MX233 that allows it to boot from an SD card is disabled. So you need to blow this bit.

Once you have the above sorted, things will work just fine.

Hope this helps.
CW

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