[IA64-SGI] SGI Altix cross partition functionality (2nd

This patch contains the shim module (XP) which interfaces between the
communication module (XPC) and the functional support modules (like XPNET).

Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/arch/ia64/sn/kernel/xp_nofault.S b/arch/ia64/sn/kernel/xp_nofault.S
new file mode 100644
index 000000000000..b772543053c9
--- /dev/null
+++ b/arch/ia64/sn/kernel/xp_nofault.S
@@ -0,0 +1,31 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2004-2005 Silicon Graphics, Inc.  All Rights Reserved.
+ */
+
+
+/*
+ * The xp_nofault_PIOR function takes a pointer to a remote PIO register
+ * and attempts to load and consume a value from it.  This function
+ * will be registered as a nofault code block.  In the event that the
+ * PIO read fails, the MCA handler will force the error to look
+ * corrected and vector to the xp_error_PIOR which will return an error.
+ *
+ *      extern int xp_nofault_PIOR(void *remote_register);
+ */
+
+        .global xp_nofault_PIOR
+xp_nofault_PIOR:
+        mov     r8=r0                   // Stage a success return value
+        ld8.acq r9=[r32];;              // PIO Read the specified register
+        adds    r9=1,r9                 // Add to force a consume
+        br.ret.sptk.many b0;;           // Return success
+
+        .global xp_error_PIOR
+xp_error_PIOR:
+        mov     r8=1                    // Return value of 1
+        br.ret.sptk.many b0;;           // Return failure
+