SYNOPSIS

int i915_gem_object_get_fence(struct drm_i915_gem_object * obj);

ARGUMENTS

obj

object to map through a fence reg

DESCRIPTION

When mapping objects through the GTT, userspace wants to be able to write to them without having to worry about swizzling if the object is tiled. This function walks the fence regs looking for a free one for obj, stealing one if it can't find any.

It then sets up the reg based on the object's properties: address, pitch and tiling format.

For an untiled surface, this removes any existing fence.

RETURNS

0 on success, negative error code on failure.

AUTHORS

Jesse Barnes <[email protected]>
Intel Corporation,         
        

Initial version

Laurent Pinchart <[email protected]>
Ideas on board SPRL,         
        

Driver internals

Daniel Vetter <[email protected]>
Intel Corporation,         
        

Contributions all over the place

Lukas Wunner <[email protected]>

vga_switcheroo documentation

COPYRIGHT