The new 21.4 version of Linux for Tegra (L4T) has been released for the NVIDIA Jetson TK1 Development Kit. Go to the Linux For Tegra R21.4 release page to get the new goodness.
Here’s a list of what’s new:
 Enabled Tegra system profiler
 Fixed gst-omx compile time errors, added README and source files
 Updated Jetson TK1 pinmux configuration
 Rework of modeswitch/vt-switch handling in X/OpenGL
 xhci firmware cfgtbl and logging enhancements
 Enabled and tuned CPU frequency boost on input event
 Adds support for X.org ABI 17, 18 and 19
 Image rotation support documentation
 Improved device tuning on Jetson TK1
Also in the release are fixes for over 65 issues that have been reported in L4T. This release promises to be the best one yet, go check it out!