From 07b3693f175a0a601a53cba656940aaec8bd9949 Mon Sep 17 00:00:00 2001 From: Joel Sherrill Date: Fri, 28 Aug 1998 13:21:53 +0000 Subject: Base files --- doc/bsp_howto/target.t | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 doc/bsp_howto/target.t (limited to 'doc/bsp_howto/target.t') diff --git a/doc/bsp_howto/target.t b/doc/bsp_howto/target.t new file mode 100644 index 0000000000..5248390cf0 --- /dev/null +++ b/doc/bsp_howto/target.t @@ -0,0 +1,34 @@ +@chapter = Target Dependent and Board Dependent Files + +RTEMS divides board dependencies into two parts : + +@itemize @bullet + +@item the CPU dependant code : it provides basics calls to the kernel, +just as the context switch or the interrupt subroutine implementations. +Sources for the supported families of processors can be found in +$RTEMS_ROOT/c/src/exec/score/cpu. A good starti ng point for a new family +of processors is the no_cpu directory, which holds both prototypes and +descriptions of each needed CPU dependant function. + +@item the board dependant code : it includes support for a given board, +such as the board initialization code and drivers for the various devices: +clock, UARTs, ethernet board, etc. + + +@end itemize + +Porting RTEMS on a new board should raise two questions : + +@itemize @bullet + +@item is the main board CPU supported ? + +@item does a BSP for a similar board exists ? + +@end itemize + +If the main board CPU is supported, you will only have do write the Board +Support Package. Otherwise you'll have to write both CPU dependant code +and the BSP. One should always start writing a BSP from a similar one. + -- cgit v1.2.3