Native gfx init

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Native graphics init

Is a driver, which is written in a high level language and open source implementation to initialize the graphics hardware on a platform. It might implement only a subset of possible resolution, a subset of possible color depth and work only on a subset of available connectors.

Even though coreboot can run VGA Option ROMs, those aren't called native graphics init.

Short forms

  • NGI : native graphics initialization
  • GFX init : graphics initialization

Usage in coreboot

Usually the full color depth and native screen resolution is used. If (x86) VGA hardware is present, one can not assume that it has been initialized at all.

Libgfxinit in coreboot

libgfxinit is a graphics initialization (aka modesetting) library for embedded environments. It currently supports only Intel hardware, more specifically the Intel Core processor line.

It can query and set up most kinds of displays based on their EDID information. You can, however, also specify particular mode lines.

libgfxinit is written in SPARK, an Ada subset with formal verifica- tion aspects. Absence of runtime errors can be proved automatically with SPARK GPL 2016.

"C" native graphics init on pre haswell platforms

On some pre Haswell Intel platforms the graphics can be initialized using C code, but only on the internal LVDS connector.