Architecture and Instructions for Accessing Multi-Dimensional Formatted Surface Memory

• US 20110074802A1
• Filed: 09/24/2010
• Published: 03/31/2011
• Est. Priority Date: 09/25/2009
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: NVIDIA Corporation
• Inventors: Johnson, Richard Craig, Fahs, Brian, Nickolls, John R., Lindholm, John Erik, Nyland, Lars
• Granted Patent: US 9,519,947 B2
• Time in Patent Office: Days
• US Class Current: 345/564
• CPC Class Codes: G06T 1/60 Memory management

Abstract

One embodiment of the present invention sets forth a technique for a program to access multi-dimensional formatted graphics surface memory. Multi-dimensional memory objects called “surfaces” stored in a user-specified data or pixel format and arranged in a graphics optimized layout are accessed by programs using surface instructions. A set of memory access instructions e.g., load, store, reduce, and atomic, referred to as surface instructions, may be used to access the surfaces. Coordinate bounds checking is performed with configurable clamping. Caching behavior may also be specified by the surface instructions. Data format conversion and packing to a specified storage format is supported for store, reduction, and atomic surface instructions. Data format conversion and unpacking from a specified storage format is supported for loads and atomic surface instructions.

Claims

1. A method for accessing multi-dimensional formatted surface memory by a program, comprising:

receiving a surface instruction that specifies coordinates of samples stored in a multi-dimensional formatted surface;

computing an address of a location in the multi-dimensional formatted surface memory based on the coordinates and attributes of the multi-dimensional formatted surface, wherein the attributes of the multi-dimensional formatted surface are controlled by a program; and

accessing the samples stored in the multi-dimensional formatted surface using the address.

2. The method of claim 1, wherein the surface instruction specifies the coordinates in bytes.

3. The method of claim 1, wherein the multi-dimensional formatted surface is configured by the program to access the samples in a pattern using multi-dimensional tiled addressing.

4. The method of claim 1, further comprising:

determining that the location is out-of-bounds of the multi-dimensional formatted surface; and

returning a default value for the surface instruction based on a mode specified by the instruction.

5. The method of claim 1, further comprising:

determining that the location is out-of-bounds of the multi-dimensional formatted surface; and

discarding the surface instruction based on a mode specified by the surface instruction.

6. The method of claim 1, further comprising:

determining that the location is out-of-bounds of the multi-dimensional formatted surface; and

reading data stored at a nearest location that is nearest to the location within the multi-dimensional formatted surface based on a mode specified by the instruction.

7. The method of claim 1, further comprising:

determining that the location is out-of-bounds of the multi-dimensional formatted surface; and

writing data to a nearest location that is nearest to the location within the multi-dimensional formatted surface based on a mode specified by the surface instruction.

8. The method of claim 1, further comprising caching data read from or written to the location based on a mode specified by the surface instruction.

9. The method of claim 1, further comprising:

receiving a second surface instruction that is configured to query an attribute of the multi-dimensional formatted surface; and

returning the attribute of the multi-dimensional formatted surface.

10. The method of claim 1, further comprising:

determining that the surface instruction is configured to store data to the multi-dimensional formatted surface; and

configuring a parallel thread processor that is coupled to the multi-dimensional formatted surface memory to convert the data to a format specified for the multi-dimensional formatted surface by the program before storing the data.

11. The method of claim 1, further comprising:

determining that the surface instruction is configured to load data from the multi-dimensional formatted surface; and

configuring a parallel thread processor that is coupled to the multi-dimensional formatted surface memory to convert the data from a format specified for the multi-dimensional formatted surface by the program before returning the data.

12. The method of claim 1, further comprising:

determining that the surface instruction is configured to perform an atomic operation on data from the multi-dimensional formatted surface; and

configuring a parallel thread processor that is coupled to the multi-dimensional formatted surface memory to convert the data from a format specified for the multi-dimensional formatted surface by the program before performing the atomic operation on the data.

13. The method of claim 1, further comprising:

determining that the surface instruction is configured to perform an atomic reduction operation on data from the multi-dimensional formatted surface; and

configuring a parallel thread processor that is coupled to the multi-dimensional formatted surface memory to convert the data from a format specified for the multi-dimensional formatted surface by the program before performing the atomic reduction operation on the data.

14. The method of claim 1, wherein the surface instruction is configured to load data from the multi-dimensional formatted surface, store data to the multi-dimensional formatted surface, query an attribute of the multi-dimensional formatted surface, perform an atomic operation on data from the multi-dimensional formatted surface, or perform an atomic reduction operation on data from the multi-dimensional formatted surface.

15. A computer-readable storage medium storing instructions that, when executed by a processor, cause the processor executing a program to access a multi-dimensional formatted surface memory, by performing the steps of:

receiving a surface instruction that specifies coordinates of samples stored in a multi-dimensional formatted surface;

computing an address of a location in the multi-dimensional formatted surface memory based on the coordinates and attributes of the multi-dimensional formatted surface, wherein the attributes of the multi-dimensional formatted surface are controlled by a program; and

accessing the samples stored in the multi-dimensional formatted surface using the address.

16. The computer-readable storage medium of claim 15, wherein the surface instruction specifies the coordinates in bytes.

17. The computer-readable storage medium of claim 15, wherein the multi-dimensional formatted surface is configured by the program to access the samples in a pattern using multi-dimensional tiled addressing.

18. The computer-readable storage medium of claim 15, further comprising:

determining that the location is out-of-bounds of the multi-dimensional formatted surface; and

returning a default value for the instruction based on a mode specified by the instruction.

19. The computer-readable storage medium of claim 15, further comprising caching data read from or written to the location based on a mode specified by the surface instruction.

20. A system for executing a compute program that accesses multi-dimensional formatted surface memory, the system comprising:

a parallel thread processor coupled to the multi-dimensional formatted surface memory and configured to;

receive a surface instruction that specifies coordinates of samples stored in a multi-dimensional formatted surface;

compute an address of a location in the multi-dimensional formatted surface memory based on the coordinates and attributes of the multi-dimensional formatted surface, wherein the attributes of the multi-dimensional formatted surface are controlled by a program; and

access the samples stored in the multi-dimensional formatted surface using the address.