440 PCI adapter card DMA question

Matt Porter porter at cox.net
Sat Aug 17 06:50:24 EST 2002

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On Fri, Aug 16, 2002 at 11:39:15AM -0700, Khai Trinh wrote:
> On one of your response email to me, you said the
> 440GP maps PCI<->PLB 1:1 and I can use the PCI bus
> address directly as a PLB address to program the 440GP
> DMA controller.
> The thing is that the DMA high and low register only
> allows 36-bit programming whereas the PCI bus address
> given to me by the Host is 64-bit.

I was answering with respect to the Ebony PCI-X host bridge

> Don't I have to manually setup the PCI-PLB mapping
> before I can program the DMA controller? OR the 440
> kernel has already handle that?

The PCI-X host bridge configuration in the Ebony port is
implemented for host operation only (i.e. it has set up
windows and controls BAR assignment within a controlled
PCI address space).  If you need a special translation
for your particular adapter application, you will need
to modify that setup accordingly.

Matt Porter
porter at cox.net
This is Linux Country. On a quiet night, you can hear Windows reboot.

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