TECHNIQUES FOR CONTROLLING FRAME REFRESH

• US 20110242116A1
• Filed: 03/25/2011
• Published: 10/06/2011
• Est. Priority Date: 03/31/2010
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Satyanantha, Rama Gopal Musunuri, Kumar, Suresh, Nath, Siddhartha
• Granted Patent: US 8,933,951 B2
• Time in Patent Office: Days
• US Class Current: 345/522
• CPC Class Codes: G09G 2340/12 Overlay of images, i.e. displayed pixel being the result of switching between the corresponding input pixels
• CPC Class Codes: G09G 2360/18 Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 5/363 Graphics controllers

Abstract

Techniques are described that track the lines and pixels in a frame buffer in the host system that are being modified and transmit these modified scan lines and modified pixel locations to the self refresh display instead of entire contents of the frame buffer. The graphics adapter informs the self refresh display of the modified scan lines or pixel information and then sends the pixel data over the communications channel to the display. Custom codes can be used to identify and transmit modified scan lines and pixels to the self refresh display logic.

Claims

1. A computer-implemented method comprising:

determining whether a request to render a rectangle comprises a request to render a rectangle on a display;

determining scan and pixel lines associated with the rectangle;

informing a self refresh display logic that pixels of the scan and pixel lines are to be transmitted to a buffer accessible to the self refresh display logic; and

transmitting pixels of the scan and pixel lines to the buffer, wherein the pixels of the scan and pixel lines comprises one of (1) pixels of scan and pixel lines modified from a previous displayed frame or (2) an entire frame of pixels.

2. The method of claim 1, wherein the determining whether a request to render a rectangle comprises a request to render a rectangle on a display comprises determining whether a flip request is associated with a buffer that is to store the rectangle.

3. The method of claim 1, further comprising:

requesting overwriting of the scan and pixel lines in the buffer.

4. The method of claim 3, further comprising:

providing contents of the buffer for display.

5. The method of claim 1, further comprising:

powering down a display engine in response to completion of transmitting pixels of the scan and pixel lines to the buffer.

6. The method of claim 5, further comprising:

placing graphics memory in lower power mode in response to completion of transmitting pixels of the scan and pixel lines to the buffer.

7. The method of claim 1, wherein the transmitted pixels of the scan and pixel lines comprise an entire frame of pixels in response to modified scan and pixel lines being scattered around a surface of a frame.

8. A computer-readable medium stored on a fixed medium comprising instructions, which when executed by a machine, cause the machine to:

receive a request to render a drawing, wherein the request identifies whether the drawing is to be written to a frame buffer and the frame buffer is to be flipped;

identify each rectangle associated with the request that is changed from a previous display of a frame;

determine line and pixel locations of each rectangle associated with the request that is changed from a previous display of a frame; and

request transmission to a target buffer of one of (1) the images associated with the determined line and pixel locations or (2) an entire frame buffer.

9. The medium of claim 8, wherein the machine is to request transmission of images of an entire frame buffer when the determined line and pixel locations are scattered around a frame.

10. The medium of claim 8, wherein to request transmission of one of the images associated with the determined line and pixel locations comprises a request to overwrite the determined scan and pixel lines in the target buffer.

11. The medium of claim 8, further comprising instructions that cause a computer to:

request powering down a display engine in response to transmitting one of the images associated with the determined line and pixel locations or an entire frame buffer to the target buffer.

12. The medium of claim 8, further comprising instructions that cause a computer to:

place a graphics memory in lower power mode in response to transmitting one of the images associated with the determined line and pixel locations or an entire frame buffer to the target buffer.

13. The medium of claim 8, further comprising instructions that cause a computer to:

request refresh of a display using contents of the target buffer.

14. A system comprising:

a display device;

a target buffer accessible to the display device; and

a host system configured to;

determine modified scan lines and pixel locations relative to a previously displayed frame based on a request to draw a rectangle and

transmit pixels associated with the request to the target buffer, wherein the pixels comprise the pixels of the modified scan lines and pixel locations.

15. The system of claim 14, wherein the target buffer is to overwrite pixels with the transmitted pixels.

16. The system of claim 14, wherein to determine modified scan lines and pixels relative to a previously displayed frame based on a request to draw a rectangle, the host system is to determine whether a flip request is associated with a buffer that stores the rectangle.

17. The system of claim 14, wherein to transmit pixels, the host system is to transmit an entire frame stored in a frame buffer instead of pixels of the modified scan lines and pixel locations in response to the pixels of the modified scan lines and pixel locations being scattered around a surface of a frame.

18. The system of claim 14, wherein the host system comprises a display engine and a memory device and wherein the host system is to reduce power consumption of the display engine and the memory device in response to transmission of pixels to the target buffer.

19. The system of claim 14, further comprising a controller, wherein the host system is to inform the controller of scan lines and pixel locations of the transmitted pixels.

20. The system of claim 14, further comprising a controller, wherein the controller is to refresh the display with image from the target buffer.