The NVIDIA Tegra 3 (Kal-El) is the forthcoming quad-core platform that's derived from the ARM Cortex-A9 MPCore and boasts a 12-core NVIDIA GPU with 3D stereo support. This is a very low-power NVIDIA GPU on a 40nm TSMC process and can handle 1080p H.264/AVC video decode. It's expected that the first Tegra 3 hardware should be shipping before year's end while it will become more common in 2012. It's said that Kal-El will be about five times faster than NVIDIA's current Tegra 2 platform.
Published on Tuesday, a day after the Linux 3.1 kernel release, was a patch series that enables the "Tegra 30" (also referred to as the T30) support for the Linux kernel (here's the start) on the kernel mailing list. The new kernel config entry describes it as, "Support for NVIDIA Tegra T30 processor family, based on the ARM CortexA9MP CPU and the ARM PL310 L2 cache controller."
The patch series supports the Tegra 3 SoC as well as NVIDIA's "Cardhu" development board for this soon-to-ship platform.
While Texas Instruments and Samsung have been working on their own open-source DRM drivers that provide KMS support (although no open 3D acceleration) for some of their SoCs, NVIDIA hasn't published any specifications or code to enable a DRM/KMS driver for the Tegra 3 Kal-El or previous-generations of their ARM-based platform. In talking with some from NVIDIA's Tegra team back in August at LinuxCon Vancouver 2011, their open-source position is unlikely to change for graphics in the near future.