BSP Developer's Guide

VxWorks 5.5
BSP Developer’s Guide
information on configuring the agent and the agent’s initialization sequence, see
the Tornado User’s Guide: Setup and Startup.
If the INCLUDE_USR_APPL is defined, the code executes the USER_APPL_INIT
macro. However, you must make sure the USER_APPL_INIT macro is a valid C
statement.
2.4 Mistakes To Be Avoided
Most of the mistakes listed below could be summarized as doing the right thing in
the wrong place or at the wrong time. Context matters.
Forgetting About LOCAL_MEM_LOCAL_ADRS
Many BSP writers assume that LOCAL_MEM_LOCAL_ADRS is zero and fail to
include it in macros that need to be offset by the start of memory. Most users do not
change the value of LOCAL_MEM_LOCAL_ADRS, but this problem tends to be
copied and replicated throughout development projects.
Doing Too Much in romInit.s
Many BSP writers try to put too much device initialization code into romInit.s. Use
the initialization in romInit.s as just a preliminary step. Handle the real device
initialization in sysHwInit( ) in sysLib.c. See romInit.s: romInit( ), p.33.
Doing Too Little in sysALib.s
Many BSP writers believe that any initialization done in romInit.s only needs to be
done once. The routine sysInit( ), in sysALib.s, should repeat all initialization
done by romInit.s. It may skip memory controller setup in some situations. Failure
to do this requires users to rebuild boot ROMs for simple configuration changes in
their VxWorks images. See sysALib.s: sysInit( ), p.34.
Modified Drivers Put in the Wrong Directory
BSP writers frequently modify Wind River device drivers, as well as provide their
own drivers. These BSP-specific drivers must be delivered in BSP-specific
directories and not in the Wind River directories target/src/drv and target/h/drv.
BSP-specific code belongs in the BSP-specific directory target/config/bspname. This
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