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Altera_Forum
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10 years ago

Cannot enumerate/read USB mass storage if Linux booted from USB

Hello, I am trying to boot from the USB2.0 OTG port on my Altera SoCKit board (from Terasic), running Linux 3.18.20. I have a strange problem that I have tried to isolate as much as possible. ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
10 years ago

Problem solved:

U-boot doesn't reset the hardware with the 'usb stop' command.

Issuing a reset via the csftrst bit of the grstctrl register for the appropriate USB port using the u-boot 'mw' command after the zImage/dtb were loaded into memory (and after 'usb stop' was issued for good measure) did the trick.

Example: mw ffb40010 1

I can now boot from a USB stick.

Hope this helps anyone else out there trying to do the same!

George Broz

Moog Industrial Group