BSP Developer's Guide

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BSP Organization
The entry point of the VxWorks image, _sysInit, is located in sysALib.s. It is the
first code executed after booting (see sysALib.s: sysInit( ), p.34). It is usual here to
perform all the functions performed by romInit.s, except for system memory
setup. The memory system should be initialized at this stage of the startup
procedure.
Unlike romInit.s, code in sysALib.s does not need to be written as PIC or to use
the ROM_ADRS macro to remap absolute addresses. It can call out to other
modules and routines.
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sysLib.c
sysSerial.c
sysScsi.c
This file contains the C source of target-specific, system-dependent sysLib
routines. These routines provide the board-level interface on which VxWorks and
application code can be built in a system-independent way. Note that sysLib.c can
include drivers from the src/drv directory and that these drivers can include some
of the routines listed below. For more information, see 5. Driver Guidelines and
F. Generic Drivers.
Driver setup and initialization is usually done in a subfile, which is included in
sysLib.c. Common subfiles are named: sysSerial.c, sysScsi.c, sysNet.c, and so on.
The purpose of using subfiles is keeping the setup and initialization of a particular
device constant across all architectures. The setup file for one board using a
particular device should be the same for any other board using that same device.
Not every feature of a particular board is necessarily supported by this BSP
abstraction. Some boards provide functions with jumpers or PALs instead of
software controllable/readable registers. Other hardware configurations might
not support some normally expected basic features.
When features are missing, it is usually safe to code an empty stub that returns
ERROR or NULL (whichever is appropriate), if any return value is required.
This optional file contains all the serial I/O setup and initialization for the SIO
device drivers. It is not separately compiled, but is included from sysLib.c. The
purpose of separating serial initialization from sysLib.o is to modularize the code
and allow reuse of code between BSPs.
This optional file contains the SCSI-2 setup and initialization for the BSP. Like
sysSerial.c, it is included in sysLib.c.
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