The PA specific directory contains the remaining components necessary to build the bootstrap loader: the boot program proper and additional standalone library routines and device drivers. It also includes the mkboot program which is used to create a LIF format file from the SOM or ELF binary. This file is suitable for installation into /usr/mdec where it can be installed with the ``-B'' option of disklabel, and interpreted by the boot ROM.

The boot loader does supports the full:

devicetype(adaptor, controller, unit, partition)pathname

The bootstrap has not yet been integrated into the kernel build environment: it still uses a simple BSD-style makefile.

There is currently no machine dependent code for mig.

PA specific code in libmach all pertains to the ``standalone'' version; i.e. the version linked in with standalone Mach applications such as the Lites server. Most of these files, in the standalone sub-directory, are the so-called ``millicode'' routines which provide support for the compiler; e.g. indirect function calls, integer multiplication and division. There are also assembly versions of basic functions such as bzero, bcopy and setjmp/longjmp support.

C-threads support includes primitives for context-switching (co-routine calls), spin locks, and thread startup. Changes and fixes were also necessary to the machine independent part of cthreads to handle ``upward'' (toward higher addresses) growing stacks and reverse polarity locks which require explicit initialization (a zero-valued lock is taken on the PA). These were deemed potentially machine independent features that should be supported in a general fashion.

For the include tree, machine contains machine dependent ``specializations'' of standard include files. Here are the definition of necessary basic Mach types such as spin locks and thread state, special exception code values, the system call trap template, and architecture specific info such as page size and address ranges. sa contains a few miscellaneous files for standalone programs.

The kernel proper has a number of sub-directories. aux contains auxiliary programs for building the kernel itself, currently just the ``genassym'' program. bogus has all the device/pseudo-device header files normally created by the BSD config program. This directory should go away when a more dynamic configuration scheme is adopted. boot_ufs contains the old in-kernel bootstrap and default pager code from Mach3. This is all machine independent code, but is used only by the PA and hence wound up here. hpdev includes all the device driver code that is common between our BSD ports to the hp300/400 (68k) and hp700/800 (PA) platforms. There is an indirect console driver, a serial-port driver, the device independent code for the raw (grf) and terminal emulator (ite) interfaces to framebuffers, and a driver for the keyboard/mouse (hil) interface. All of these drivers are shared between our Mach and BSD kernels with the MACH_KERNEL ifdef providing the distinction.

More on the console interface.

Explain that HIL shared queues, and mmap'ed GRF don't work.

ITE doesn't support color or soft keys.

emulator trampoline, sysent tables, syscall stubs