Uncoupling a central processing unit from its associated hardware for interaction with data handling apparatus alien to the operating system controlling said unit and hardware

• US 5,155,809 A
• Filed: 05/17/1989
• Issued: 10/13/1992
• Est. Priority Date: 05/17/1989
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Baker, Ernest D., Joyce, James M., Dinwiddie, John M. Jr., Sanderson, Kenneth R., Grice, Lonnie E., Loffredo, John M.
• Primary Examiner(s): Lall, Parshotam S.
• Assistant Examiner(s): COSIMANO, EDWARD R
• Application Number:
  US07/353,114
• Time in Patent Office: 1,245 Days
• Field of Search: 364/228, 364/228.8, 364/232.3
• US Class Current: 709/227
• CPC Class Codes: G06F 11/1608 Error detection by comparing the output signals of redundant hardware G06F11/1629, G06F11/1666 take precedence; error detection or correction in information storage based on relative movement between record carrier and transducer G11B20/18; checking static stores for correct operation G11C29/00; for logic circuits H03K19/003, H03K19/007; for pulse counters or frequency dividers H03K21/40
• CPC Class Codes: G06F 11/1616 where the redundant component is an I/O device or an adapter therefor
• CPC Class Codes: G06F 11/1625 in communications, e.g. transmission, interfaces
• CPC Class Codes: G06F 11/1633 using mutual exchange of the output between the redundant processing components
• CPC Class Codes: G06F 11/1641 where the comparison is not performed by the redundant processing components
• CPC Class Codes: G06F 11/1658 Data re-synchronization of a redundant component, or initial sync of replacement, additional or spare unit
• CPC Class Codes: G06F 11/1679 at clock signal level
• CPC Class Codes: G06F 12/023 Free address space management
• CPC Class Codes: G06F 12/0284 Multiple user address space allocation, e.g. using different base addresses interprocessor communication G06F15/163
• CPC Class Codes: G06F 13/368 with decentralised access control

Abstract

The functions of two virtual operating systems (e.g., S/370 VM, VSE or IX370 and S/88 OS) are merged into one physical system. Partner pairs of S/88 processors run the S/88 OS and handle the fault tolerant and single system image aspects of the system. One or more partner pairs of S/370 processors are coupled to corresponding S/88 processors directly and through the S/88 bus. Each S/370 processor is allocated from 1 to 16 megabytes of contiguous storage from the S/88 main storage. Each S/370 virtual operating system thinks its memory allocation starts at address 0, and it manages its memory through normal S/370 dynamic memory allocation and paging techniques. The S/370 is limit checked to prevent the S/370 from accessing S/88 memory space. The S/88 Operating System is the master over all system hardware and I/O devices. The S/88 processors access the S/370 address space in direct response to a S/88 application program so that the S/88 may move I/O data into the S/370 I/O buffers and process the S/370 I/O operations. The S/88 and S/370 peer processor pairs execute their respective Operating Systems in a single system environment without significant rewriting of either operating system. Neither operating system is aware of the other operating system nor the other processor pairs.

Claims

1. In a data processing system, a combination comprising

a processor unit and associated hardware for processing information under control of an operating system,

information handling apparatus alien to the operating system, and

means uncoupling the processor unit from said hardware and coupling the processor unit to said apparatus for interaction with said apparatus.

2. The system set forth in claim 1 wherein said means performs said uncoupling and coupling functions without the use of operating system services and without rejection by said operating system.

3. In a data processing system, a combination comprising

a processor unit and associated hardware for processing information under control of a virtual operating system,

information handling apparatus alien to the operating system, and

means including an application program running on said processor unit uncoupling the processor unit from said hardware and coupling the processor unit to said apparatus for interaction between said processor unit and said apparatus in accordance with said application program and without knowledge thereof by the operating system.

4. The system set forth in claim 3 wherein said means further comprises,

said processor unit effective during the execution of selected instructions of said application program for applying one of a plurality of preselected virtual addresses on its processor address bus, and

address decode logic means responsive to one of said preselected addresses on said bus for uncoupling the processor unit from said hardware and coupling the processor unit to the information handling apparatus for execution of said selected instructions in said processor unit and apparatus.

5. The system set forth in claim 4

wherein said processor unit includes an address strobe line coupled to said hardware, and

wherein said address decode logic means responds to the presence of one of said preselected addresses on said bus to block a processor signal on said address strobe line from said hardware and to couple said signal to the information handling apparatus for rendering the apparatus effective during the execution of one of said selected instructions.

6. In a data processing system, a combination comprising a first processing unit and hardware including a main storage and a plurality of I/O devices for executing programs under control of a first virtual operating system,

a second processing unit, alien to the first operating system for executing programs under control of a second operating system,

means including an application program running on the first processing unit uncoupling the first processing unit from said hardware and coupling the first processing unit to the second processing unit, and

means controlled by the first processing unit and the application program while that unit is uncoupled from said hardware for transferring data between the first and second processing units.

7. The system of claim 6 wherein said transfer of data between the first and second processing units is indiscernible to the first operating system.

8. In a data processing system,

a first processing unit and hardware including a main storage and a plurality of I/O devices for executing programs having a first instruction architecture under control of a first virtual operating system,

a second processing unit alien to said operating system, for executing programs having a different instruction architecture under control of a second virtual operating system differing from the first operating system,

means including an application program in the first processing unit uncoupling the first processing unit from said hardware and coupling the first processing unit directly to the second processing unit, and

means controlled by the first processing unit and the application program while that unit is uncoupled from said hardware for exchanging at least one of command and data information between the second unit and the first unit.

9. The system of claim 8 further comprising

means controlled by the first processing unit and the application program for converting command and data information transferred from the second unit to the first unit to commands executable by and data useable by the first processing unit.

10. The system of claim 9 wherein said first processing unit and said hardware are operated to process said converted command and data information under control of said first operating system.

11. In a data processing system,

a first processing unit and associated hardware for executing programs under control of a first virtual operating system, said processing unit having a processor address bus,

a second processing unit alien to said operating system, for executing programs under control of a second virtual operating system,

means directly coupling the second processing unit to the first processing unit for the transfer of information therebetween,

means including an application program running on the first processing unit for applying selected virtual addresses to said address bus,

logic means responsive to one of said selected virtual addresses on said bus for uncoupling the first processing unit from its associated hardware, and

means controlled by the first processing unit and the application program while the first processing unit is uncoupled for passing at least one of command and data information between the second unit and the first unit via said direct coupling means.

12. The system of claim 11 wherein said first processing unit includes a processor data bus and a processor control bus, and wherein said direct coupling means directly couples the second processing unit to the processor address, data and control buses of the first processing unit.

13. The system of claim 11 further comprising

means controlled by the first processing unit and the application program for converting command and data information transferred from the second processing unit to the first processing unit to commands executable by and data useable by the first processing unit.

14. The system of claim 13 where said first processing unit and hardware are operated to process said converted commands and data under control of said first operating system.

15. In a data processing system,

a first processing unit and associated hardware for executing programs under control of a first virtual operating system,

a second processing unit and associated hardware for executing programs under control of a second virtual operating system;

each processing unit and its associated hardware being alien to the operating system of the other processing unit;

means directly coupling the processing units to each other for the transfer of information therebetween;

means associated with each processing unit and including a respective application program running on that processing unit uncoupling that processing unit from its associated hardware and coupling that processing unit to the direct coupling means; and

means controlled by each processing unit and its respective application program while that unit is uncoupled, for exchanging information between that unit and the direct coupling means, whereby information may be exchanged directly between the processing units.

16. The system of claim 15 further comprising,

means associated with each one of the processing units for converting commands and data received from the other processing unit to commands executable by and data useable by the one processing unit.

17. The system of claim 15 wherein each said uncoupling means further includes

processing unit means responsive to an instruction of its respective application program for applying a unique virtual address on an address bus of that processing unit, and

logic means responsive to said unique virtual address for uncoupling its respective processing unit from its respective hardware.

18. The system of claim 15 wherein each direct coupling means includes a local storage accessible by each of the processing units while uncoupled for processing unit intercommunication.

19. The system of claim 18 wherein each processing unit and its associated hardware are operated to process its received and converted commands and data under control of its respective operating system.

20. In a data processing system,

a first processor unit and first associated hardware including main storage and I/O apparatus for processing information under control of a first virtual operating system,

a second processor unit and second associated hardware including main storage and I/O apparatus for processing information under control of a second virtual operating system,

each processor unit and its associated hardware being alien to the operating system of the other processor unit and hardware,

means directly coupling said processor units, and

means associated with the processor units and including respective application programs running on the processor units for uncoupling the processor units from their respective hardware and coupling the processor units to the direct coupling means for the transfer of commands and data between the processor units.

21. In a data processing system having a processor unit and hardware for processing information under control of an operating system, a method for permitting interaction between the processor unit and data handling apparatus alien to the operating system in a manner which is indiscernible by the operating system comprising the steps of

uncoupling the processor unit from said hardware during instruction execution;

and

while the processor unit and hardware are uncoupled, coupling the processor unit to said apparatus for interaction therewith in accordance with said instruction execution.

22. In a data processing system of the type in which a processor unit interacts with hardware for processing information under control of an operating system, a method for transferring data between the processor unit and data handling apparatus alien to the operating system comprising the steps of

executing a selected data transfer instruction of a special application program in said processor unit;

during the execution of said instruction, uncoupling the processor unit from said hardware and coupling the processor unit to the data handling apparatus for transferring data between the processor unit and the apparatus in accordance with said instruction, whereby the data transfer is indiscernible by the operating system.

23. A method for uncoupling a processing unit from its associated hardware to permit an information transfer, in a manner indiscernible by its operating system, with apparatus alien to its operating system, comprising the steps of

executing in said processing unit a selected data transfer instruction of a special application program,

applying a predetermined virtual address on the address bus of the processing unit during the execution of said instruction.

decoding said address,

responsive to said decoding, blocking a processing unit address strobe signal from the associated hardware and applying it to the alien apparatus, thereby uncoupling the processing unit from its associated hardware and coupling the processing unit to the alien apparatus for data transfer.

24. The method of claim 23 further comprising the step of

terminating the instruction execution upon completion of the data transfer.

25. A method for uncoupling a processing unit from its associated hardware to permit an information transfer, in a manner indiscernible by its operating system, with apparatus alien to its operating system, comprising the steps of

executing in said processing unit a selected data transfer instruction of a special application program,

placing a predetermined virtual address on the address bus of the processing unit during the execution of said instruction,

decoding said address,

uncoupling the processing unit from its associated hardware and coupling the processing unit to the alien apparatus in response to said decoding for execution of said data transfer instruction with said alien apparatus.

26. The method of claim 25 further comprising the step of,

terminating the instruction execution upon completion of the data transfer.

27. In a data processing system, a combination comprising

a processor unit and associated hardware for processing information under control of an operating system,

information handling apparatus alien to the operating system, and

means uncoupling the processor unit from said hardware and coupling the processor unit to said apparatus to permit operation of said unit in isolation from said hardware and operating system while interacting with said apparatus.

28. The system set forth in claim 27 wherein said means performs said uncoupling and coupling functions in a manner indiscernable by said operating system.

29. A method for coupling a first processor operating under the control of one operating system to one or more I/O units without software drivers in said operating system for said units comprising the steps of

coupling the first processor for direct information transfer with a data processing system, including said I/O units and a second processor operated under the control of a second operating system,

selectively uncoupling the second processor from the data processing system in a manner indiscernable to the second operating system by means including an application program executing on the second processor,

selectively passing I/O commands and data from the first processor and its operating system to the second processor while uncoupled,

converting said commands and data to commands executable by and data usable by the second processor and its operating system, and

processing the converted commands and data in the data processing system.

30. The method of claim 29 further comprising the step of

selectively passing data directly from the second processor to said first processor while the second processor is uncoupled.

31. A method of coupling one processor of one architecture operating under one operating system to another processor of a different architecture operating under a different operating system, said other processor normally coupled to hardware including a main storage and a plurality of I/O devices, comprising the steps of

uncoupling the other processor from its hardware by means including an application program running on said other processor,

operating the other processor as an I/O controller for the one processor by

a. passing I/O commands and data from the one processor to the other processor in its uncoupled state,

b. converting said commands and data to commands executable by and data useable by the other processor, and

c. executing said converted commands in the other processor in its coupled state.

32. A method of transferring information from one processor operating under the control of one operating system to a second processor coupled to and operating with hardware including a main storage and a plurality of I/O devices under the control of a second operating system differing from the one operating system comprising the steps of

coupling one processor to the second processor via a direct path means,

uncoupling the second processor from the hardware and coupling the second processor to the direct path means under control of the second processor and an application program in a manner indiscernable to the second operating system,

while said second processor is uncoupled, transferring information between said one processor and said second processor via said direct path means under the control of said second processor and an application program running thereon, whereby the transfer is indiscernable to the second operating system.

33. In a data processing system,

a first processor having a bus structure and interacting with associated hardware for processing information under control of an operating system,

a second processor alien to the operating system and having a bus structure and means for initiating interrupt requests on its processor bus for the first processor for the transfer of commands and data thereto,

a direct coupling mechanism between the processors having a local storage for storing commands and data being transferred between the processors, a local bus structure adapted to couple the local storage to the processor bus structures of each processor for command and data transfers therebetween and logic means including a direct memory access controller (DMAC) for controlling the transfer of commands and data between said processor bus structures and the local storage via the local bus structure,

logic means including the DMAC responsive to one of the interrupt requests from the second processor for applying an interrupt signal to the first processor,

means including the first processor responsive to said signal for operating the first processor in isolation from its associated hardware and operating system for accessing an application program having a routine for servicing the interrupt request, and

means operating the first processor in isolation from its associated hardware and operating system under the control of said application program for transferring commands and data between the processors via said direct coupling mechanism pursuant to said interrupt request.

34. In a data processing system,

a processor and associated hardware for processing information under control of an operating system, said operating system having routines for handling interrupt requests from said processing system on plural priority levels,

data handling apparatus alien to the operating system and including means for initiating additional interrupt requests to the processor on one of said priority levels for data transfer with the processor, said routines being unable to service the interrupt requests from said apparatus;

an application program in the processing system including an additional interrupt handler routine to service the interrupt requests from said apparatus;

means effective upon the initiation of an interrupt request from said apparatus for directing the processor to the additional interrupt handler routine without rejection by said operating system, said system thereafter effective to execute said additional interrupt handler routine on said processor; and

means including said application program running on said processor unit selectively uncoupling the processor unit from said hardware and coupling the processor unit to said apparatus for data transfer without rejection by the operating system.

35. In a data processing system,

a first processing unit and associated hardware for executing programs under control of a first virtual operating system,

a second processing unit and associated hardware for executing programs under control of a second virtual operating system;

each processing unit and its associated hardware being alien to the operating system of the other processing unit;

means directly coupling the processing units to each other for the transfer of information therebetween;

means in each processing unit for initiating interrupt requests to the other processing unit when a data transfer is required between the processors,

means in each processing unit including an application program with interrupt handler routines to service interrupt requests from the other processing unit;

means associated with each processing unit and including a respective application program running on that processing unit uncoupling that processing unit from its associated hardware and coupling that processing unit to the direct coupling means; and

means controlled by each processing unit and its respective application program while that unit is uncoupled, for exchanging information between that unit and the direct coupling means, whereby information may be exchanged directly between the processing units.

36. In a data processing system, a combination comprising

a processor unit and associated hardware for processing information under control of an operating system,

information handling apparatus alien to the operating system, and

means uncoupling the processor unit from said hardware and coupling the processor unit to said apparatus to permit operation of said unit in isolation from said hardware and operating system while interacting with said apparatus, whereby said means performs said uncoupling and coupling functions without using the services of said operating system and without rejection by said operating system.

37. In a data processing system,

a first processor unit and first associated hardware for processing information under control of a first virtual operating system,

a second processor unit and second associated hardware for processing information under control of a second virtual operating system,

each processor unit and its associated hardware being alien to the operating system of the other processor unit and hardware,

means directly coupling said processor units, and

means associated with each processor unit and including a respective application program running on that processor unit for uncoupling that processor unit from its respective hardware and coupling that processor unit to the direct coupling means for the transfer of data between the processor units without using the services of and without rejection by either operating system.