What does i915 gmbus DPB mean?

On my machine, i915 gmbus dpb refers to my DVI-connected monitor. i915 is the Intel graphics module. The Display Data Channel (DDC) runs on the I²C bus and is mainly used to transmit Extended Display Identification Data (EDID) information from the display to the computer.

Which Intel integrated graphics chipsets does the drm/i915 driver support?

The drm/i915 driver supports all (with the exception of some very early models) integrated GFX chipsets with both Intel display and rendering blocks. This excludes a set of SoC platforms with an SGX rendering unit, those have basic support through the gma500 drm driver.

What is the i915 driver?

The i915 driver supports dynamic enabling and disabling of entire hardware blocks at runtime. This is especially important on the display side where software is supposed to control many power gates manually on recent hardware, since on the GT side a lot of the power management is done by the hardware.

Why i915 is used for FBC?

It comes from keeping the memory footprint small and having fewer memory pages opened and accessed for refreshing the display. i915 is responsible to reserve stolen memory for FBC and configure its offset on proper registers. The hardware takes care of all compress/decompress.