Blackfin: adjust asm constraints with NMI workaround
authorMike Frysinger <vapier@gentoo.org>
Tue, 31 Jul 2012 09:38:56 +0000 (05:38 -0400)
committerSonic Zhang <sonic.zhang@analog.com>
Mon, 13 May 2013 07:47:24 +0000 (15:47 +0800)
commit2e2ed3f4ff5f21a5c39394c55d361e826238ce2d
tree558ea823e0acbeb2005fbd996f5df582c8e36a7b
parente0ae433e9283728ce3f25e0d3794291c11e48f5e
Blackfin: adjust asm constraints with NMI workaround

Newer gcc versions will sometimes use a Preg when "r" constraints, but
that'll fail if we use an Ireg in the assignment.  So force the code
to always use a Dreg.

This also fixes early boot crashes for older Blackfin parts when compiled
with gcc-4.5.  This version ends up selecting the same register for the
input and output variables which corrupts the output assignment triggering
an exception.
P2 = 0xffe02008; /* EVT2 */
R0 = RETS;
CALL 1f;
RTN;
1: P2 = RETS; <-- BAD
RETS = R0;
[P2] = P2; <-- BAD

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
arch/blackfin/cpu/initcode.c