Neale, The QDIO code in VM/ESA was delivered in source in 2.4, it now appears to be OCO in z/VM. I had a look at when we first got 2.4, and I think one sets the device in QDIO mode by means of a special CCW (started by ssch), after which the signal adapter instruction can be used for data transfer.
Jan Jaeger. ps It seems rather silly to me to first deliver source, and then go to oco... "Ferguson, Neale" wrote: > > > Hipersockets is an extension of Queued Direct I/O (QDIO) used > > by Fast Ethernet Express and Gigabyte Express OSA cards, which > > is only avialble on later CEC's. QDIO is also used by FICON on > > the zSeries. The extension is called IQDIO (internal QDIO). It > > is really a combinatoin of "software" and LIC (licensed > > internal code) and requires a LIC update to the processor, > > only available to later processors. It requires a new control > > unit (IQD) on a channel in the IOCDS and communications is via > > the "start subchannel" interface to a subchannel address. > > I thought (after reading Systems Journals and other IBM pubs) that > the QDIO facility was driven by the "Signal Adaptor" op-code. This > is an undocumented op-code (along with others such as "Locate > Channel Buffer" - look at comments in various control blocks to > discover these). Do you mean that IQDIO is a feature that allows > QDIO type devices and data transfers to be initiated by SSCH? > > I'm not sure why SIGA etc. are undocumented. Who else is prod- > ucing z900 clones? I understand for the OSA (non-QDIO types) that > the technology has been licensed and so there would be an exposure > to IBM if it were to "open" things. However, for QDIO OSA and for > the any forthcoming FICON drivers are we going to see these OCO > device drivers popping out like doughnuts? > > When all things are considered QDIO is just a variation of memory > mapped I/O that I first encountered this with the Apple II (I > understand DEC pioneered this type of thing). So I'm not sure what > the paranoia over leaving out the description out of PoPs.
