> > > 2. Only 4x devices is supported, you need to be careful not to overuse > > > > Could you elaborate on this please? What happens if you are not careful? > > How does management know what the limits are? > > It means the user might use more space than 768MB for mmconfig, > which is [0x80000000m 0xb0000000). If such situation happens, seabios > will ignore all extra pxb-pcie devices and not adding e820 entry for them, > which makes all the devices under them unworkable.
Ypu should clearly note that this is a limitation of the seabios support patches then, so not an issue of the qemu patches. > As for the management, will some checks when adding mcfg be enough for > management? Or I can maintain a variable to indicate how many space > have been consumed and warn the user if they exceed the threshold? > The latter allows us to do the check when the pxb-pcie is initializing. I think qemu should not apply any restrictions here. cheers, Gerd