In message 004B1D7A5257174C9044A1B7BD0E60ED0178CC5C@ratatosk.combitechsystems.com you >>>wrote:

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I'm trying to get three serial ports up and running simultaneously. I'm using slightly modified TQM823L based board (added FPGA) with serials on SMC1, SMC2 and SCC3. The problem is to get SCC3 alive into Linux. A detailed study of the problem follows shows that when using SCC3 for console in u-boot, it also works in Linux, but when using SMC1 (or SMC2) for console, SCC3 does not work in Linux. So I have come to my own humble conclusion that it has something to do with the initialization of the serial devices in u-boot. Long story short:

No, you are wrong. Linux drivers must never rely on any initialization done by any boot loader.

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I _really_ want the console on SMC1 and I need the SCC3 serial working on the side. Are there any appropriate ways of achieving this (I've tried enabling both SMC1 and SCC3 for console but that did not do the trick)?

Fix your Linux driver / port. This is not an U-Boot issue.

Best regards,

Wolfgang Denk

Thanks for this simple clarification. After moving the custom u-boot init code to Linux, everything works like a charm!

Cheers. Bjorn Ostby