I've just been playing with an application which needed the 48MHz clock
output from the PXA270. We've allocated the pin for it but nothing was
coming out. A bit of trial and error (the Intel documentation was no
help at all) revealed that it is shared with the USB device clock, and
thus has to be enabled in the CKEN register.
I've modded bootldr (in the branches/bootldr32-pxa-sa1100 branch) so
that it enables this by default. This should be of benefit to many
applications which want to use the FPGA. It shouldn't break anything
else, but I'm prepared to be proven wrong.
I also noticed that the Balloon-specific GPIO Alternate Function
register settings were #ifdef'ed by a CONFIG_MACH_H5400, which made no
sense at all to me, and may even have meant that bootldr wasn't taking
any notice of them (there is another set of bare hex numbers of unknown
provenance in the relevant #else clause). They're already encased in a
#ifdef CONFIG_MACH_BALLOON, so I removed the #ifdef CONFIG_MACH_H5400.
The values we spent so long carefully defining in balloon3-init.h are
thus absolutely, definitely the ones getting used now, which can only be
a good thing. Probably.
Chris
--
Chris Jones -
chris@martin-jones.com
Martin-Jones Technology Ltd, makers of Solidlights
148 Catharine Street, Cambridge, CB1 3AR, UK
Phone +44 (0) 1223 655611 Fax +44 (0) 870 112 3908
http://www.solidlights.co.uk/
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