[PATCH 2.6.11-rc4] ppc: add support for Radstone ppc7d boards

[James Chapman]

Revised patch for Radstone PPC7D board support.

Signed-off-by: James Chapman <jchapman at katalix.com>

- use mv64x60_set_bus() to setup for PCI scans rather than
   writing to chip P2P_CONFIG registers directly.

Mark A. Greer wrote:

> James Chapman wrote:
> 
>> Mark A. Greer wrote:
>>
>>>  > +       /* Setup P2P for PCI#0 */
>>>  > +       val32 = mv64x60_read(&bh, MV64x60_PCI0_P2P_CONFIG);
>>>  > +       val32 &= ~(0x00ffffff);
>>>  > +       val32 |= ((bh.hose_a->first_busno & 0xff) << 16);
>>> etc.
>>>
>>> Do you really use the P2P bridge?  Unless I missed something, I think 
>>> it remains disabled.  You shouldn't need it unless you have PCI 
>>> devices on one hose directly accessing PCI devices on the other 
>>> hose.  The P2P stuff seems complicated & unnecessary.
>>
>>
>>
>> Thinking about this more, what is really being configured here is the
>> primary bus number before the scan is performed. If the bus number
>> doesn't match the hose's primary bus number, the mv64x60 will issue
>> Type 2 PCI config cycles instead of Type 1 and the scan will fail.
>>
>> This board has an on-board PCI-X bridge and potentially other PCI
>> bridges on PMC cards. I found that I had to init the P2P_CONFIG
>> primary bus value before scan in order for the PCI scan of bus 2
>> to work (hose_a has PCI busses 0 and 1).
>>
>> I think the writes to the P2P config registers are necessary.
> 
> 
> 
> mv64x60_set_bus() is supposed to do that.  Try doing your bus numbering 
> setup/bus scanning like what's in ev64260.c.  If there is still a 
> deficiency, then we should fix up that routine.
> 
> Mark
> 
> 
> 
> 


-- 
James Chapman
E-mail  : jchapman at katalix.com
PGP key : http://www.katalix.com/~jchapman/pgpkey.txt
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