[PATCH] Disable VSX instruction

[Paulo Flabiano Smorigo <pfsmorigo@linux.vnet.ibm.com>]

VSX bit is enabled by default for Power7 and Power8 CPU models,
so we need to disable them in order to avoid instruction exceptions.
Kernel will activate it when necessary.

Also-By: Adhemerval Zanella <azanella@linux.vnet.ibm.com>
---
 ChangeLog                                 | 10 ++++++++++
 grub-core/kern/powerpc/ieee1275/startup.S | 10 ++++++++++
 2 files changed, 20 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 192e8bc..c1b0637 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2014-09-25  Paulo Flabiano Smroigo  <pfsmorigo@linux.vnet.ibm.com>
+
+	Disable VSX instruction
+
+	VSX bit is enabled by default for Power7 and Power8 CPU models, so we
+	need to disable	them in order to avoid instruction exceptions. Kernel
+	will activate it when necessary.
+
+	* grub-core/kern/powerpc/ieee1275/startup.S: Disable VSX.
+
 2014-09-25  Colin Watson  <cjwatson@ubuntu.com>
 
 	Fix in-tree --platform=none
diff --git a/grub-core/kern/powerpc/ieee1275/startup.S b/grub-core/kern/powerpc/ieee1275/startup.S
index 21c884b..c4621a6 100644
--- a/grub-core/kern/powerpc/ieee1275/startup.S
+++ b/grub-core/kern/powerpc/ieee1275/startup.S
@@ -20,6 +20,8 @@
 #include <grub/symbol.h>
 #include <grub/offsets.h>
 
+#define MSR_VSX 0x80
+
 .extern __bss_start
 .extern _end
 
@@ -28,6 +30,14 @@
 	.globl	start, _start
 start:
 _start:
+ _start:
+
+    /* Disable VSX interrupt instruction */
+	mfmsr  0
+	oris   0,0,MSR_VSX
+	mtmsrd 0
+	isync
+
 	li      2, 0
 	li      13, 0
 
-- 
1.8.1.4