svn commit: r191362 - head/sys/powerpc/booke

[Marcel Moolenaar]

On Apr 21, 2009, at 11:00 AM, Rafal Jaworowski wrote:

> On 2009-04-21, at 19:04, Marcel Moolenaar wrote:
>
>> o  Carve out the first 1MB of physical memory. The MPC85xx has
>>    DMA problems with addresses below 1MB. Ideally busdma knows
>>    how to avoid allocating below 1MB for MPC85xx, but that
>>    requires a bit more work. For now, ignore the 1MB of DRAM.
>
> Could you elaborate a bit on the last item? What is the faulty  
> scenario, is this a known h/w defect documented somewhere?

Not documented and no indication of a failure from PCI/PCI-X
or PCI Express host controllers, nor the device doing the DMA
and also not from the coherency engine on the MPC85xx.

The only noticeable behaviour is a lack of data transfer by
virtue of having unchanged memory after DMA write completion.

Observed with MPC8544 PCI, MPC8544 PCI Express and MPC8548
PCI Express.

FYI,

-- 
Marcel Moolenaar
xcllnt at mac.com