xscale: some wp detail added to user manual

Hi everyone (again),

Watchpoints on xscale are quirky, so I thought a little explanation in the
user's manual was warranted.

Comments gratefully received.

Last one, Øyvind :-)

Thanks,
Mike

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
This commit is contained in:
Mike Dunn 2010-09-19 15:30:59 -07:00 committed by Øyvind Harboe
parent ebfb2f4f37
commit 103c1f9525
1 changed files with 9 additions and 0 deletions

View File

@ -6390,6 +6390,15 @@ the @code{xscale debug_handler} command. The allowed locations for the
debug handler are either (0x800 - 0x1fef800) or (0xfe000800 -
0xfffff800). The default value is 0xfe000800.
XScale has resources to support two hardware breakpoints and two
watchpoints. However, the following restrictions on watchpoint
functionality apply: (1) the value and mask arguments to the @code{wp}
command are not supported, (2) the watchpoint length must be a
power of two and not less than four, and can not be greater than the
watchpoint address, and (3) a watchpoint with a length greater than
four consumes all the watchpoint hardware resources. This means that
at any one time, you can have enabled either two watchpoints with a
length of four, or one watchpoint with a length greater than four.
These commands are available to XScale based CPUs,
which are implementations of the ARMv5TE architecture.