Graphics address remapping table

The graphics address remapping table (GART), sometimes known as the graphics translation table (GTT), is an I/O memory management unit (IOMMU) used by Accelerated Graphics Port (AGP) and PCI Express (PCIe) graphics cards. The GART allows the graphics card direct memory access (DMA) to the host system memory, through which buffers of textures, polygon meshes and other data are loaded.

GART is used as a means of data transfer between the main memory and video memory, but can also be used to expand the amount of video memory available for graphics cards, particularly for cards with no dedicated video memory such as Intel HD Graphics processors.

Jeff Hartmann served as the primary maintainer of the Linux kernel's agpgart driver, which began as part of Brian Paul's Utah GLX accelerated Mesa 3D driver project. The developers primarily targeted Linux 2.4.x kernels, but made patches available against older 2.2.x kernels. Dave Jones heavily reworked agpgart for the Linux 2.6.x kernels, along with more contributions from Jeff Hartmann.

In FreeBSD, the agpgart driver appeared in its 4.1 release.

AGPgart support was introduced into Solaris Express Developer Edition as of its 7/05 release.

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