On Thu, 4 Oct 2007, Maciej W. Rozycki wrote: > to be careful about the device #31 in general; it is seldom used anyway as > there are only 20 IDSEL lines defined by the standard and they are usually > mapped starting from the device #0. Just to correct myself not to confuse anybody -- there are actually 21 IDSEL lines which map from bits 31:11 of the address provided for Type 0 configuration access cycles -- at most one bit from that range is ever set for such cycles. The issuing bridge is free to set no bits for device numbers it has no assigned IDSEL line for; such transactions will never be claimed by any device and thus will always terminate with Master-Abort. Maciej
