USB On PCM043?

Sascha Hauer s.hauer at
Fri Jul 20 04:04:35 EDT 2012

On Thu, Jul 19, 2012 at 08:56:35PM +0000, Jerry Kirk wrote:
> > > We have been attempting to get USB Host mode working under Barebox(2012-07-0)
> > > a PCM043 platform (i.mx35), but we are having a bit of trouble.
> > 
> > Could it be that the USB clock operates at the wrong rate? I think it
> > should be 60MHz.
> We're not certain how to verify the clock setting for USB in Barebox.
> We have used "dump_clocks" but are not certain which of these clocks
> the USB clock is derived from. We think we have it set to the same
> settings as the Eukrea board.

The i.MX SoCs have a clko pin which can be muxed to different clocks. I
don't know if this is accessible on the pcm043, but if yes, you could
switch it to the USB clock and measure the clock.
Otherwise it might be good to run a current -rc kernel, you can then
see the complete clock tree in debugfs


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