nuttx

arch/x86/include/README.txt

^^^^^^^^^^^^^^^^^^^^^^^^^^^



This directory holds x86-specific header files.  The top-level header files in

arch/x86/include simply include corresponding header files from lower lower-

level chip-specific and architecture-specific directories.



Architecture-Specific Directories

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^



Architecture-specific directories hold common header files for specific x86

architectures.  Separating these header file makes it easy to manage such

things as differences in sizeof(long) on 32- and 64-bit x86 architectures.



i486

  This directory holds definitions appropriate for any instantiation of the

  32-bit i486 architecture.



Chip-Specific directories

^^^^^^^^^^^^^^^^^^^^^^^^^



The same x86 architecture may be realized in different chip implementations.

For SoC chips, in particular, on-chip devices and differing interrupt

structures may require special, chip-specific definitions in these chip-

specific directories.



qemu

  This is the implementation of NuttX on the QEMU x86 simulation.