OMAP Frame Buffer ARGB4444

Andrew Poole

I am currently using the PowerVR SGX to draw some graphics. I have noticed that it is possible to output ARGB8888 to an EGL Window Surface for which the OMAP outputs the RGB components to the DSS Data pins. This appears to draw all 32 bits of data to the frame buffer.

Is it possible to output ARGB4444 to an EGL Window Surface instead? Thereby drawing a full 16bit ARGB pixel into the frame buffer and outputting a full 16bit ARGB pixel on the DSS data pins per pixel clock cycle.

Thanks,

Andy

over 13 years ago

0 Andrew Poole over 13 years ago

Intellectual 570 points

I have tried modifying the omaplfb_displayclass.c file (in the omaplfb kernel module) to add a new pixel format; PVRSRV_PIXEL_FORMAT_ARGB4444, which is defined in include4/servicesext.h. After setting the framebuffer (using fbset) to the new ARGB4444 format, my application recognizes an ARGB4444 EGL Window Surface. The problem is that the application crashes when it attempts to draw anything to the framebuffer.

Does anyone from TI have any thoughts on this? Is what I am trying to do even possible?

Thanks,

Andy

0 Ranjith Parakkal over 13 years ago in reply to Andrew Poole

TI__Prodigy 390 points

ARGB4444 colour format is not supported by the SGX.

0 Ranjith Parakkal over 13 years ago in reply to Ranjith Parakkal

TI__Prodigy 390 points

ARGB32 is supported by both SGX and DSS.

0 Andrew Poole over 13 years ago in reply to Ranjith Parakkal

Intellectual 570 points

Hi Ranjith,

Thank you for your reply. So the format is a limitation of the PowerVR SGX? I know the SGX appears to support RGB565 and ARGB8888, do you know what other formats it supports? I am very interested in knowing if I can render ARGB in a lower depth than 32 bit.

Thanks,

Andy

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OMAP Frame Buffer ARGB4444