the following patch was just integrated into master: commit b92e54333f75baa86bcda67b1beeb19669250f03 Author: Vadim Bendebury vbendeb@chromium.org Date: Fri Oct 3 09:47:13 2014 -0700
mips: do not place branch instructions in branch delay slot
A branch instruction in a branch delay slot confuses the execution pipeline and causes an exception.
bootblock.S was written 'by hand', has a branch instruction in branch delay slot and includes '.set noreorder' directive, which causes it to crash when trying to branch to main().
Adding a nop instruction fixes the problem. Also adding a nop after the last branch in the file just in case main() returns and the object linked next starts with a branch.
BUG=chrome-os-partner:31438 TEST=Running on the simulator can reach main() now
Change-Id: I0882b2eb5ce426f5a311018ffbb6f37a2ca64d98 Signed-off-by: Vadim Bendebury vbendeb@chromium.org Reviewed-on: https://chromium-review.googlesource.com/221421 Reviewed-by: Aaron Durbin adurbin@chromium.org Reviewed-on: http://review.coreboot.org/9183 Reviewed-by: Ronald G. Minnich rminnich@gmail.com Tested-by: build bot (Jenkins)
See http://review.coreboot.org/9183 for details.
-gerrit