It's a bug fix release, here are the resolved issues:
Release Note for Development Tools v11.2.1
Previous release: 11.2.0
* Debug view in XDE was incorrect making it difficult/impossible to switch threads
* XTAG-2 JTAG state machine reset now works correctly without TRST
* reset command after device detach now functions correctly
* UART connection now closed correctly on xgdb exit
* Debugger on OSX no longer drops connection to FTDI based development boards during execution
* board support
* Duplicated link endpoints in XN are now reported.
* Additional notation for link endpoints on L devices is now supported: XLx where x is [ABCDEFGHIJKLMNOP].
* Clearer XMOS link naming scheme used in L2 XN file
* Flash programming
* The 11.2 version of xflash could not produce a flash image to boot a system with more than 2 switches. This is now fixed.
* Enhancement to SPI specs: changed unnecessarily large sector size (32768) to 4096 for Atmel AT25FS010.
* Applications written to flash by xflash using an XN file which contains streaming debug links (for xscope) will often fail to run correctly. To avoid this, xflash now declines to operate with any XN file which includes streaming debug links.
* Previously the default boot loader would choose the last image in flash with a non-zero version number rather than the one with the highest version number overall. This is now fixed.
* Fixed boot failure with N-L1/2 systems with multiple boot sites.
* XScope print redirection now flushes host buffer correctly
* client tools installer
* SetEnv.bat can now be run from any directory
Download the new version here