Boot Loaders


Das U-Boot (Universal Bootloader) is an open source, primary boot loader used in embedded devices. A wide variety of MIPS cores and boards are supported in head-of-tree U-Boot. It’s used extensively on a wide variety MIPS development and production boards.

Source can be obtained from


Boot MIPS is example code for MIPS IP Cores. It is intended to aid you in becoming familiar with the initialization of a MIPS Core. Boot-MIPS is a stand-alone executable that runs from reset, initializing core resources to the point where every processing element in the system is executing shared C code, with its own stack and coherent shared global data.

An application note outlining Boot-MIPS can be downloaded by clicking here


YAMON™ is the PROM monitor used on MIPS development boards. Yamon is still in use on legacy development boards but is deprecated for new projects. To support existing users of these, and the QEMU project, YAMON is now available under the GPL License.

  • The same binary image is used for all boards and CPUs supported by YAMON
  • YAMON detects the specific board and CPU at run-time
  • The binary image contains both little and big-endian code
  • YAMON detects the endianness at run-time and executes the appropriate code
  • The size of SRAM as well as other SDRAM parameters are detected at run-time
  • PCI auto-detection and auto-configuration is performed for boards supporting PCI
  • Applications can be downloaded using serial ports or Ethernet (as supported in hardware)
  • Includes traditional shell commands (load, go, dump, etc.)
  • Shell implements command line history and editing functionality
  • Includes GDB stub allowing remote GDB debug using serial port
  • Includes floation point emulator
  • BIOS-like functionality intended for applications using vector based call interface

YAMON includes boot code as well as traditional monitor functionality used for loading, executing and debugging applications. YAMON source code is highly portable to other MIPS-based platforms. The source code and build environment for YAMON is available from MIPS.

Documentation and Downloads