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README.md

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 # rtems6-powerpc
-toolchain for cross compilation to rtems6 beatnik
+
+A container that makes the RTEMS powerpc beatnik Board Support Package (BSP).
+
+This container gets the sources from RTEMS releases, builds the toolchain and then compiles the BSP.
+
+The current configuration is:-
+- rtems version: 6.1-rc2
+- patches for MVME5500 boards used at DLS
+- legacy network stack
+
+This container can be run to experiment with building components with the RSP and prebuilt rtems6 toolchain.
+
+See https://docs.rtems.org/branches/master/user/start/index.html
+
+To just get the Board Support Package (BSP) with toolchain, you can extract these products into your own container with:
+
+```
+ENV RTEMS_VERSION=6.1-rc2
+ENV RTEMS_TOP=/rtems${RTEMS_VERSION}-beatnik-legacy/rtems/${RTEMS_VERSION}/
+ENV RTEMS_BSP_IMAGE=ghcr.io/epics-containers/rtems6-powerpc-linux-developer
+
+COPY --from=${RTEMS_BSP_IMAGE}:${RTEMS_VERSION} ${RTEMS_TOP} ${RTEMS_TOP}
+```
+
+Or you can get the BSP locally with:
+```
+docker run --rm -v $(pwd):/workdir ghcr.io/epics-containers/rtems6-powerpc-linux-developer:6.1-rc2
+# in another terminal
+mkdir -p /rtems6-beatnik-legacy/rtems/
+docker cp $(docker ps -lq):/rtems6-beatnik-legacy/rtems/6.1-rc2/ /rtems6-beatnik-legacy/rtems/6.1-rc2/
+```
+
+IMPORTANT: the BSP contains absolute paths so you must copy it to the same path as inside the container.