AMD announced an updated SDK (software development kit) allowing programmers to tap into the GPUs (graphics processing units) of its A-Series (“Llano”) processors. Meanwhile, the Khronos Group released version 4.2 of its OpenGL specification, and AMD and Nvidia have both pledged support for it.

AMD launched its A-Series "Llano" processors in June, featuring dual- or quad-core "Stars" CPU cores as well as on-chip Radeon graphics. (The top laptop offering, the A8-3530MX4, has a 444MHz GPU clock speed and 400 GPU cores, according to the chipmaker.)

Naturally, AMD supported the processors from day one with its own "Catalyst" Windows drivers (and driver code is reportedly included in Linux 3.0 as well as a variety of earlier distros). However, Llano's onboard GPU cores can also be used for non-graphical tasks via OpenCL, the chipmaker says.

Programmers can tap into OpenCL — which the Khronos Group calls "the first open, royalty-free standard for cross-platform, parallel programming" — by using AMD's Accelerated Parallel Processing (APP) SDK. A newly released version 2.5 of this kit not only offers Llano support, but also provides enhanced performance, according to the company.

In an Aug. 1 blog entry, AMD noted that A-Series processors share common DDR3 memory, partitioning it between the CPU and the GPU. This means data can be transferred more efficiently between the CPU and the GPU, since there's no longer any constraint imposed by a PCI Express bus, the company added.

With the APP SDK version 2.5, data can now move between a CPU and GPU at up to 15GB per second, AMD says. Enhancements to the OpenCL runtime enable more efficient use of available GPU compute capabilities by reducing kernel launch times and PCI Express transfer overheads, the chipmaker adds.

In addition, according to AMD, the AMD APP SDK provides broad multi-GPU support on Windows platforms. AMD's "PowerXpress" technology is said to offer "compute performance scaling" when a device includes both a Llano processor and one or more separately installed discrete GPUs.

Graham Brown, chief technology officer of Corel Corporation, was quoted as saying, "With the introduction of the AMD A-Series APUs and these new enhancements to the SDK, AMD is removing hardware barriers and reducing coding complexity to help developers build immersive computing experiences. Leveraging open standards, AMD has created a comprehensive platform developers can use to deploy all available compute power."

An OpenGL upgrade

While the Khronos Group's OpenCL is for "general-purpose parallel programming," its OpenGL standard is described as "the most advanced and widely adopted cross-platform 2D and 3D graphics API." Coinciding with Siggraph (being held from Aug. 7-11 in Vancouver, Canada), the organization has released version 4.2 of the OpenGL spec.

According to the Khronos Group, new functionality in Open GL 4.2 includes the following:

• enabling shaders with atomic counters and load/store/atomic read-modify-write operations to a single level of a texture. These capabilities can be combined, for example, to maintain a counter at each pixel in a buffer object for single-rendering-pass order-independent transparency;
• capturing GPU-tessellated geometry and drawing multiple instances of the result of a transform feedback to enable complex objects to be efficiently repositioned and replicated; modifying an arbitrary subset of a compressed texture, without having to re-download the whole texture to the GPU for significant performance improvements;

• and packing multiple 8- and 16-bit values into a single 32-bit value for efficient shader processing with significantly reduced memory storage and bandwidth, especially useful when transferring data between shader stages.

Barthold Lichtenbelt, working group chair of the OpenGL architecture review board and and director of Tegra graphics at Nvidia, stated, "OpenGL 4.2 has integrated feedback from developers that are shipping significant OpenGL-based applications and games, making for a faster, more capable API which will continue to evolve to meet market needs." Nvidia released production Open GL 4.2 drivers for its GPUs on Aug. 8, he added.

Ben Bar-Haim, an AMD corporate vice president for software development, was quoted by the Khronos Group as having said, "AMD plans to release our OpenGL 4.2 beta drivers with the publication of the OpenGL 4.2 specification. AMD strongly supports industry standards and congratulates the Khronos Group on their success in the rapid evolution of OpenGL and its other open standards that enable brilliant computing experiences."

Further information

More information on version 2.5 of AMD's APP SDK may be found on the company's Developer Central website. The AMD APP SDK OpenCL Programming Guide is downloadable in PDF format.

More information on Nvidia's OpenGL 4.2 drivers may be found, along with downloads, on the company's Developer Zone website. Meanwhile, we could not locate updated drivers on the AMD site at the time of writing, but they should become available on AMD's graphics drivers download page.

Jonathan Angel can be reached at [email protected] and followed at www.twitter.com/gadgetsense.

This article was originally published on LinuxDevices.com and has been donated to the open source community by QuinStreet Inc. Please visit LinuxToday.com for up-to-date news and articles about Linux and open source.