[OpenBIOS] [commit] r1096 - trunk/openbios-devel/arch/sparc32

repository service svn at openbios.org
Sat Jan 26 13:50:15 CET 2013


Author: blueswirl
Date: Sat Jan 26 13:50:15 2013
New Revision: 1096
URL: http://tracker.coreboot.org/trac/openbios/changeset/1096

Log:
SPARC32: WIM register update delay

The SparcV8 standard states, page 134:
"If any of the three instructions after a write state register
instruction reads any field that was changed by the original
write state register instruction, the contents of that
field read by that instruction are undefined."

The restore instruction depends on the %WIM register,
three NOPs must be inserted.

Signed-off-by: Olivier DANET <odanet at caramail.com>
Signed-off-by: Blue Swirl <blauwirbel at gmail.com>

Modified:
   trunk/openbios-devel/arch/sparc32/wuf.S

Modified: trunk/openbios-devel/arch/sparc32/wuf.S
==============================================================================
--- trunk/openbios-devel/arch/sparc32/wuf.S	Sat Jan 26 13:50:13 2013	(r1095)
+++ trunk/openbios-devel/arch/sparc32/wuf.S	Sat Jan 26 13:50:15 2013	(r1096)
@@ -131,6 +131,7 @@
 	/* LOCATION: Window 'O' */
 
 	restore %g0, %g0, %g0
+        WRITE_PAUSE
 
 	/* LOCATION: Window 'W' */
 



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