Abstraction of configurable processor functionality for operating systems portability

• US 6,763,327 B1
• Filed: 02/17/2000
• Issued: 07/13/2004
• Est. Priority Date: 02/17/2000
• Status: Expired due to Term

• Current Assignee: Tensilica Incorporated
• Original Assignee: Tensilica Incorporated
• Inventors: Songer, Christopher Mark, Gauthier, Marc E., Chea, Kevin C., Konas, Pavlos
• Primary Examiner(s): Ingberg, Todd
• Assistant Examiner(s): Thomson, W. D.
• Application Number:
  US09/506,433
• Time in Patent Office: 1,608 Days
• Field of Search: 703/21, 703/15, 703/20, 703/22, 703/23, 703/24, 703/26, 703/27, 710/23, 717/138, 717/134, 717/135, 717/147, 717/120, 717/106, 717/107, 709/1, 709/108, 709/107, 709/328, 709/321, 709/319, 709/324, 709/327, 709/329, 716/1, 716/4, 716/18, 716/2, 716/3, 716/17
• US Class Current: 703/21
• CPC Class Codes: G06F 9/45504 Abstract machines for programme code execution, e.g. Java virtual machine [JVM], interpreters, emulators
• CPC Class Codes: G06F 9/45533 Hypervisors; Virtual machine monitors
• CPC Class Codes: G06F 9/45541 Bare-metal, i.e. hypervisor runs directly on hardware

Abstract

A hardware abstraction layer operates as a system architectural layer between a real-time operating system and an underlying configurable processor. The hardware abstraction layer provides an abstraction of processor-specific functionality to the operating system. In particular, it abstracts configurable processor features visible to the operating system to provide a uniform, standardized interface between the operating system and the configurable processor on which it runs. Thus, an operating system running on top of the hardware abstraction layer will work on all configurations of the processor which differ from one another only in the configuration parameters covered by the hardware abstraction layer. The hardware abstraction layer may be generated using the same information that is used to describe the features being configured in the configurable processor. Automatic generation of the HAL greatly eases use of the HAL and the configurable processor, since the user is not required to manually write the HAL or adapt an existing one based on the processor configuration parameters.

Claims

1. A method for allowing a desired operating system to be executed on different configurations of a base configurable processor comprising:

automatically providing a common software interface to a plurality of different operating systems, including the desired operating system; and

automatically providing an abstraction layer that abstracts areas of the processor configurability, such that a first software implementation of the interface and abstraction layer build is executable together with the desired operating system on a first configuration of the base configurable processor, and a second software implementation of the interface and abstraction layer build is executable together with the desired operating system on a second different configuration of the base configurable processor.

2. A software library as in claim 1, wherein the areas of processor configurability include save and restore of configurable processor state.

3. A software library as in claim 1, wherein the areas of processor configurability include co-processor initialization and control.

4. A software library as in claim 1, wherein the areas of processor configurability include interrupts.

5. A software library as in claim 1, wherein the areas of processor configurability include timers.

6. A software library as in claim 1, wherein the areas of processor configurability include processor instruction caches.

7. A software library as in claim 1, wherein the areas of processor configurability include processor data caches.

8. A software library as in claim 1, wherein the areas of processor configurability include processor debug features.

9. A method as in claim 1, wherein the areas of processor configurability include instruction stream disassembly.

11. A method as in claim 1, wherein the abstraction layer is operating system independent.

10. A system for generating software for execution on a configurable processor, comprising:

an interface that receives a configurable processor description, including a first configuration of the configurable processor and a second different configuration of the configurable processor; and

a build system that receives the first and second configurations and automatically generates a software implementation having an abstraction layer that abstracts configurable portions of the configurable processor, such that a first build of the software implementation is executable on the first configuration of the configurable processor and a second build of the software implementation is executable on the second configuration of the configurable processor.

12. A system as in claim 10, wherein the abstraction layer is operating system independent.

13. A method of porting a desired operating system to different configurations of a base configurable processor comprising:

providing a common software interface to a plurality of different operating systems, including the desired operating system;

receiving a first configuration of the base configurable processor;

automatically generating a first abstraction layer based on the first configuration;

building a first software implementation using the common software interface and the first abstraction layer, the first software implementation being executable together with the desired operating system on the first configuration of the base configurable processor;

receiving a second configuration of the base configurable processor, the second configuration being different than the first configuration; and

automatically generating a second abstraction layer based on the first configuration;

building a second software implementation using the common software interface and the second abstraction layer, the second software implementation being executable together with the desired operating system on the second configuration of the base configurable processor.

14. A method as in claim 13, wherein the first and second configurations include parameters for processor configurability, the parameters including two or more of save and restore of configurable processor state, co-processor initialization and control, interrupts, timers, instruction caches, processor data caches, processor debug features, and instruction stream disassembly.

15. A method of designing a configurable processor, the configurable processor having a first instruction set architecture portion that is not configurable and a second instruction set architecture portion that is user-configurable, the configurable processor being able to execute software intended for a desired operating system, the method comprising:

automatically providing a common software interface to a plurality of different operating systems, including the desired operating system;

receiving a desired configuration for the configurable processor, the desired configuration specifying parameters for configuration of the second instruction set architecture portion of the configurable processor, the parameters including two or more of save and restore of configurable processor state, co-processor initialization and control, interrupts, timers, instruction caches, processor data caches, processor debug features, and instruction stream disassembly;

automatically generating an abstraction layer based on the received configuration; and

building a software implementation using the common software interface and the abstraction layer, the software implementation being executable together with the desired operating system on the configurable processor.

16. A system for designing a configurable processor, the configurable processor having a first instruction set architecture portion that is not configurable and a second instruction set architecture portion that is user-configurable, the configurable processor being able to execute software intended for a desired operating system, the system comprising:

a common software interface to a plurality of different operating systems, including the desired operating system;

a user interface for receiving a desired configuration for the configurable processor, the desired configuration specifying parameters for configuration of the second instruction set architecture portion of the configurable processor, the parameters including two or more of save and restore of configurable processor state, co-processor initialization and control, interrupts, timers, instruction caches, processor data caches, processor debug features, and instruction stream disassembly;

means for automatically generating an abstraction layer based on the received configuration; and

means for building a implementation using the common software interface and the abstraction layer, the software implementation being executable together with the desired operating system on the configurable processor.