svn commit: r215436 - head/sys/boot/powerpc/ofw

[Andreas Tobler]

Author: andreast
Date: Wed Nov 17 19:28:48 2010
New Revision: 215436
URL: http://svn.freebsd.org/changeset/base/215436

Log:
  Make sure the .bss is cleared at the beginning. The pSeries OF ELF loader does
  not clear .bss automatically.
  
  Approved by:	nwhitehorn (mentor)

Modified:
  head/sys/boot/powerpc/ofw/start.c

Modified: head/sys/boot/powerpc/ofw/start.c
==============================================================================
--- head/sys/boot/powerpc/ofw/start.c	Wed Nov 17 19:25:37 2010	(r215435)
+++ head/sys/boot/powerpc/ofw/start.c	Wed Nov 17 19:28:48 2010	(r215436)
@@ -50,7 +50,20 @@ _start:				\n\
 	addi	%r1,%r1,stack at l	\n\
 	addi	%r1,%r1,16384	\n\
 				\n\
-	b	startup		\n\
+	/* Clear the .bss!!! */	\n\
+	li      %r0,0		\n\
+	lis     %r8,_edata at ha	\n\
+	addi    %r8,%r8,_edata at l\n\
+	lis     %r9,_end at ha	\n\
+	addi    %r9,%r9,_end at l	\n\
+				\n\
+1:	cmpw    0,%r8,%r9	\n\
+	bge     2f		\n\
+	stw     %r0,0(%r8)	\n\
+	addi    %r8,%r8,4	\n\
+	b       1b		\n\
+				\n\
+2:	b	startup		\n\
 ");
 
 void