On 2/14/06, Eugene Surovegin [off-list ref] wrote:

On Tue, Feb 14, 2006 at 08:48:56AM -0500, Ed Goforth wrote:

quoted

I posted the original from home, and didn't have the contents of the
config register.  It is
cfg     0x00103e00
Which I interpret as having bit 11 set: "1 Enable GPIO11 as GPIO11"
from the manual.

I originally tried to call ioremap64(PPC440GX_GPIO0_ADDR,) directly, bu=

t got

quoted

"unresolved symbol ioremap64".  From inspection of ioremap(), the
fixup for 0x40000700 translates to 0x140000700, and I get the same
values in my code as I see from a "/proc/ocotea/gpio".

Is my approach valid?

It seems to be.

At least I've got that. :)

Try writing the same GPIO output register value as you read from it
(without clearing bit 11). Also, try changing some other GPIO bit
(e.g. one which is not connected in your design). Maybe board hangs
exactly because you set GPIO bit 11 low :).

I have successfully written back the same values that were read from
it.  I will try your suggestion about fiddling with other GPIO bits
that we aren't (supposed to be) using.

Also, connect scope to that GPIO pin and see what is really going on.

--
Eugene

Thanks,
Ed