Hello.
Attila Kinali wrote:
To sum it up, Cardbus bridge is not a viable solution on Au1500 for
hotswapping devices, since any decent one (bus mastering) will not work.
USB2.0 should instead work with PCI based controllers, that must be
connected to the main PCI device (directly to Au1500).
We are using a board with a Au1550 with cardbus (PCI1520) and
USB2.0. The USB controller is directly connected to PCI.
Although cardbus isn't fully tested yet, USB seems to work fine
(atleast i haven't heard of any problems), but i don't know
from the top of my head which chip they used.
Also, the Au1550 doesn't seem to have the master-behind-bridge
bug as the 1500 does (at least according to the datasheet),
Reading revisions C and D of the Au1550 datasheet, I see:
4.3.9 System Considerations
The Au1550 PCI controller cannot be used with external PCI-to-PCI bridges that
have PCI bus-mastering devices on the secondary bus which target the Au1550
memory.
so i guess cardbus should work also with "decent" cards :)
OTOH, Au1550 errata I have is silent about the P2P bridges.
HTH
Attila Kinali
WBR, Sergei