Roadmap
The 2011 platform integrates CPU, GPU, Northbridge, PCIe, DDR3 memory controller, and UVD on the same integrated circuit. The CPU and GPU are coupled together using a memory controller that arbitrates between coherent and non-coherent memory request. The physical memory is partitioned between the GPU (up to 512 MB) and the CPU (the remainder).
The 2012 platform allows the GPU memory controller to freely access all available CPU memory without going through a device driver.
The 2013 platform to use a completely unified CPU and GPU memory controller.
The 2014 platform to add APU hardware context switching.
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