RPM support for BSPs
	====================

Introduction
------------

Building an rpm requires to have a tar archive of the sources, and a
rpm-spec files specifying the details of building.

To support per bsp rpms, one rpm-spec is used per BSP. 
Instead of writing one rpm-spec for each BSP, I have written a shell script
(mkspec) which generates one *.spec (rtems-<target_alias>-<bsp>.spec) per BSP
bsp from an rpm-spec template (rtems.spec.in).

A second shell script (mkrpms) is a convienience script which invokes a
sequence of building rpms for several bsps.

mkspec
------

mkspec takes two arguments: 
$1 ... the bsp to be built
$2 ... the target_alias this bsp belongs to

Invoking mkspecs will generate a rtems-<target_alias>-<bsp>.spec either in
/usr/src/packages/SPECS (SuSE convention) or 
/usr/src/redhat/SPECS (Redhat convention) or
/usr/src/SPECS

Eg. ./mkspec gensh1 sh-rtemself generates
/usr/src/packages/SPECS/rtems-sh-rtemself-gensh1.spec on SuSE-6.2.

Building BSP-rpms
-----------------

0. Login as root.

1. Install a tarball of RTEMS's sources (with version number attached!) to
/usr/src/[packages|redhat]/SOURCES
Eg. 
tar czvf /usr/src/packages/SOURCES/rtems-<VERSION>.tar.gz rtems-<VERSION>

2. Generate and install the required rpm-spec file[s]
cd rtems-<VERSION>/scripts/
mkspec <bsp> <target_alias>

3. Build the rpms
Building a binary rpm:
rpm -bb /usr/src/[packages|redhat]/SPECS/rtems-<target_alias>-<bsp>.spec

Building a source and binary rpm
rpm -ba /usr/src/[packages|redhat]/SPECS/rtems-<target_alias>-<bsp>.spec

Note: a BSP's src.rpm contains its spec-file and the tar-archive of the
sources (approx. 4-5MB per BSP). 

Known Bugs/Deficiencies
-----------------------

* All files mentioned in here are in its early infancy ;-)

* Building for a single bsp requires an own copy of the source tree inside
rpm's build directory.
* Building inside the RTEMS source tree doesn't work.
* Dependencies on toolchain-rpms not yet supported in rtems.spec.in.
* Installing multiple binary bsp rpms for the same target can cause 
warnings from rpm, because these bsp-rpms share files.
* rtems.spec.in is prepared for rpm relocation support, but RTEMS is not
relocatible (yet?)
* rtems.spec.in deserves to be extended (description, authors etc)
* The final packaging stage to build a binary rpm takes an awful lot of
time - deserves to be investigated.
* Some RTEMS's cross executables (eg. hello.exe for sparc-rtems/erc32) cause 
warnings from rpm and/or objdump. AFAIS, this is a bug in rpm.
* Probably many more ...

* Last but not least: RTEMS should be split.

Remarks
-------
* It would make sense to split RTEMS host/cross-tools and files depending on
the target only (<target_alias>/make/*.cfg -- Whow, RTEMS really has files 
which depend on the target only :) into separate rpms.
* Instead of using a single rpm-spec for each bsp, RTEMS could also use a
single rpm-spec for all (or at least a given subset of all) bsps of a target.
* rpm -b[b|a] leaves its built trees unpacked in 
/usr/src/[packages|redhat]/BUILD. Therefore you will rather soon run out of disc
space if not removing them. (Use rpm --clean -b[a|b] for cleaning them up 
automatically after building) 
* The size of binary rpms can differ up to one magnitude depending on the
target/bsp (eg. sh-rtems/gensh1 ~10MB vs. sh-rtemself/gensh1 ~32MB) 

Ralf Corsepius, 1999/10/14