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+There are various issues regarding this port:
+
+
+
+1) Legal
+
+This port is written by Andrew Bray <andy@i-cubed.demon.co.uk>, and
+is copyright 1995 i-cubed ltd.
+
+Due to the current lack of a formal release note, this is a limited
+release to OAR, and other specific parties designated by OAR who
+are involved in porting RTEMS to the PowerPC architecture.
+
+This set of release files SHOULD (IMHO) include a cpu specific
+alignment exception handler.  Ours is derived from IBM sample
+code.  I am seeking a release from IBM for this file.  In the
+mean time this file is excluded (but still included in the Makefile
+as a place-holder).
+
+
+
+2) CPU support.
+
+This release fully supports the IBM PPC403GA and PPC403GB processors.
+
+It has only been tested on the PPC403GA (using software floating
+point).
+
+With the gratefully acknowledged assistance of IBM and Blue Micro,
+this release contains code to support the following processors
+  PPC601, PPC603, PPC603e, PPC604, and PPC602.
+
+The support for these processors is incomplete, especially that for
+the PPC602 for which only sketchy data is currently available.
+
+
+
+3) Application Binary INterface
+
+In the context of RTEMS, the ABI is of interest for the following
+aspects:
+
+a)  Register usage.  Which registers are used to provide static variable
+    linkage, stack pointer etc.
+
+b)  Function calling convention.  How parameters are passed, how function
+    variables should be invoked, how values are returned, etc.
+
+c)  Stack frame layout.
+
+I am aware of a number of ABIs for the PowerPC:
+
+a)  The PowerOpen ABI.  This is the original Power ABI used on the RS/6000.
+    This is the only ABI supported by versions of GCC before 2.7.0.
+
+b)  The SVR4 ABI.  This is the ABI defined by SunSoft for the Solaris port
+    to the PowerPC.
+
+c)  The Embedded ABI.  This is an embedded ABI for PowerPC use, which has no
+    operating system interface defined.  It is promoted by SunSoft, Motorola,
+    and Cygnus Support.  Cygnus are porting the GNU toolchain to this ABI.
+
+d)  GCC 2.7.0.  This compiler is partway along the road to supporting the EABI,
+    but is currently halfway in between.
+
+This port was built and tested using the PowerOpen ABI, with the following
+caveat:  we used an ELF assembler and linker.  So some attention may be required
+on the assembler files to get them through a traditional (XCOFF) PowerOpen
+assembler.
+
+This port contains support for the other ABIs, but this may prove to be incoplete
+as it is untested.
+
+In the long term, the RTEMS PowerPC port should move to the EABI as its primary
+or only port.  This should wait on a true EABI version of GCC.
+
+Andrew Bray 18/8/1995