Fwd: PPC beginner questions

  Thanks!  I'd already seen the #1 (#2) link in the FAQ and understood
that.  I'm not doing this from userland, so I was assuming it did not apply,
although I was going to use it to play with in user space.

  The #3 comes up as an error for me, the lists.linuxppc.org domain name
does not resolve.  Several other links in the FAQ do not resolve properly.
One now points to a page that has paid links to other pages.


thanks again,
Wade



On 8/21/06, Fillod Stephane [off-list ref] wrote:

 Your question is a linuxppc-embedded FAQ. User-land access

is documented in Denx's FAQ[1], and accessible through shorter URL[2].

For more information, please follow this thread[3] (not ppc specific
actually).



[1]
http://www.denx.de/twiki/bin/view/PPCEmbedded/DeviceDrivers#Section_AccessingPeripheralsFromUserSpace

[2] http://tinyurl.com/6c7th

[3] http://lists.linuxppc.org/linuxppc-embedded/200403/msg00059.html



In kernel land, ioremap() is all you need.



Don't forget to use the 'eieio' asm instruction if you want explicit I/O
ordering.



Regards,

--

Stephane




 ------------------------------

*Envoyé :* lundi 21 août 2006 15:51
*Objet :* PPC beginner questions




  I'm new to the PPC and I have a few questions.  I have written a  driver
in the past for the X86 family, using i/o ports, but it was kernel 2.0 and
i/o ports are not mmu handled.
  I've been looking through the archive and I am slowly growing more
confused.

  We are using Xilinx with PPC built in.

   The PPC has a memory management unit.  All of the IP we've added is
mapped to physical addresses.

   1. Can I access the memory the peripherasl are mapped to directly
within the driver without going through functions?
       if NOT, then Do I use
          1. ioremap(),
          2. request_mem_region(),
          3. request_region()
          4. something else?

   2.  Are there any gotcha's with the ppc 405 that Xilinx uses that I
should know about?


thanks,
wade