On 11 Aug 2003 17:55:50 -0400 John Dennis <[EMAIL PROTECTED]> wrote: > Now it seems to me that using extra machine instructions (asm version) > or no-op IO is inherently a risky solution to this problem. It would > appear there is some interval of time one must wait for individual VGA > bus transactions complete. The number of extra machine instructions > and/or no-op IO to insert seems to be purely a guess and highly > dependent on the processor and the bus its sitting on.
I/O space port accesses have well defined strict timing requirements. If I remember correctly, these timing requirements are specifically mentioned in the PCI specifications. Therefore my understanding is that you can depend upon them taking a specific amount of time to complete. _______________________________________________ Devel mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/devel
