Building a ChorusOS System Image with a New BSP/DRV Component

A kernonly system image is a minimal system image that contains no POSIX file system or networking layers. It is recommended that when creating a system image for a new board you initially create a kernonly system image, to limit the testing and debugging to the essential microkernel components only. Once this minimal configuration works, you can enable the support of other devices used by the POSIX OS layer and configure and build a standard ChorusOS system image that includes this layer.

To create a new ChorusOS kernonly system image you need to create a build directory and use the configure(1CC) command to prepare the build directory for ChorusOS, as shown below.

% cd build_dir
% configure -b $TOOLS $KERNEL -s $DRV $BSP
% make
% make kernonly

The two components DRV and BSP indicate the paths of your new BSP and you will notice that they are source components (indicated by the -s option). For more detailed information on building a system image with a new BSP component and booting the ChorusOS system image on a new target board see the ChorusOS 5.0 Source Delivery Guide and Part II of the ChorusOS 5.0 Installation Guide.

• DRV: the generic and family specific drivers and BSP source component. This must be set to the installed directory pathname source_dir/nucleus/bsp. If you have added other drivers that are not within the ChorusOS DRV source tree then you may need to add a MYDRV component which is set to the pathname of your driver source.

• BSP: the platform-specific source component. This must be set as the pathname of the my_board directory which contains the boot, reboot and debug agent parts of the BSP.

It is important to note that when adding new drivers to an existing BSP, the BSP should be considered as a new one. This is because the addition of new drivers to an existing BSP modifies some source files, in particular the initial device tree and the target.xml. (On some platforms the target.xml file may be split into multiple files: drivers.xml, drvlist.xml and target.xml. In this situation the drivers.xml and drvlist.xml files are included in the target.xml file. )