powerpc: Prepare xmon_save_regs for use with kdump

Today the arch/powerpc/xmon/setjmp.S file contains only the
xmon_save_regs function.  We want to use it for kdump purposes, so
let's move the file into arch/powerpc/kernel/ and give the function a
more generic name (ppc_save_regs).

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 78 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 92673b43858d..616c8891d858 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -102,6 +102,10 @@ endif
 
 obj-$(CONFIG_PPC64)             += $(obj64-y)
 
+ifneq ($(CONFIG_XMON),)
+obj-y                           += ppc_save_regs.o
+endif
+
 extra-$(CONFIG_PPC_FPU)         += fpu.o
 extra-$(CONFIG_PPC64)           += entry_64.o
 
diff --git a/arch/powerpc/kernel/ppc_save_regs.S b/arch/powerpc/kernel/ppc_save_regs.S
new file mode 100644
index 000000000000..5113bd2285e1
--- /dev/null
+++ b/arch/powerpc/kernel/ppc_save_regs.S
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 1996 Paul Mackerras.
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ *
+ * NOTE: assert(sizeof(buf) > 23 * sizeof(long))
+ */
+#include <asm/processor.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+
+/*
+ * Grab the register values as they are now.
+ * This won't do a particularily good job because we really
+ * want our caller's caller's registers, and our caller has
+ * already executed its prologue.
+ * ToDo: We could reach back into the caller's save area to do
+ * a better job of representing the caller's state (note that
+ * that will be different for 32-bit and 64-bit, because of the
+ * different ABIs, though).
+ */
+_GLOBAL(ppc_save_regs)
+        PPC_STL r0,0*SZL(r3)
+        PPC_STL r2,2*SZL(r3)
+        PPC_STL r3,3*SZL(r3)
+        PPC_STL r4,4*SZL(r3)
+        PPC_STL r5,5*SZL(r3)
+        PPC_STL r6,6*SZL(r3)
+        PPC_STL r7,7*SZL(r3)
+        PPC_STL r8,8*SZL(r3)
+        PPC_STL r9,9*SZL(r3)
+        PPC_STL r10,10*SZL(r3)
+        PPC_STL r11,11*SZL(r3)
+        PPC_STL r12,12*SZL(r3)
+        PPC_STL r13,13*SZL(r3)
+        PPC_STL r14,14*SZL(r3)
+        PPC_STL r15,15*SZL(r3)
+        PPC_STL r16,16*SZL(r3)
+        PPC_STL r17,17*SZL(r3)
+        PPC_STL r18,18*SZL(r3)
+        PPC_STL r19,19*SZL(r3)
+        PPC_STL r20,20*SZL(r3)
+        PPC_STL r21,21*SZL(r3)
+        PPC_STL r22,22*SZL(r3)
+        PPC_STL r23,23*SZL(r3)
+        PPC_STL r24,24*SZL(r3)
+        PPC_STL r25,25*SZL(r3)
+        PPC_STL r26,26*SZL(r3)
+        PPC_STL r27,27*SZL(r3)
+        PPC_STL r28,28*SZL(r3)
+        PPC_STL r29,29*SZL(r3)
+        PPC_STL r30,30*SZL(r3)
+        PPC_STL r31,31*SZL(r3)
+        /* go up one stack frame for SP */
+        PPC_LL  r4,0(r1)
+        PPC_STL r4,1*SZL(r3)
+        /* get caller's LR */
+        PPC_LL  r0,LRSAVE(r4)
+        PPC_STL r0,_NIP-STACK_FRAME_OVERHEAD(r3)
+        PPC_STL r0,_LINK-STACK_FRAME_OVERHEAD(r3)
+        mfmsr   r0
+        PPC_STL r0,_MSR-STACK_FRAME_OVERHEAD(r3)
+        mfctr   r0
+        PPC_STL r0,_CTR-STACK_FRAME_OVERHEAD(r3)
+        mfxer   r0
+        PPC_STL r0,_XER-STACK_FRAME_OVERHEAD(r3)
+        mfcr    r0
+        PPC_STL r0,_CCR-STACK_FRAME_OVERHEAD(r3)
+        li      r0,0
+        PPC_STL r0,_TRAP-STACK_FRAME_OVERHEAD(r3)
+        blr