powerpc: Add helper functions for transactional memory context switching

Here we add the helper functions to be used when context switching.  These
allow us to fully reclaim and recheckpoint a transaction.

We introduce a new paca field called tm_scratch to help us store away register
values when doing the low level tm reclaim register save.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/tm.h b/arch/powerpc/include/asm/tm.h
new file mode 100644
index 0000000..4b4449a
--- /dev/null
+++ b/arch/powerpc/include/asm/tm.h
@@ -0,0 +1,20 @@
+/*
+ * Transactional memory support routines to reclaim and recheckpoint
+ * transactional process state.
+ *
+ * Copyright 2012 Matt Evans & Michael Neuling, IBM Corporation.
+ */
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+extern void do_load_up_transact_fpu(struct thread_struct *thread);
+extern void do_load_up_transact_altivec(struct thread_struct *thread);
+#endif
+
+extern void tm_enable(void);
+extern void tm_reclaim(struct thread_struct *thread,
+		       unsigned long orig_msr, uint8_t cause);
+extern void tm_recheckpoint(struct thread_struct *thread,
+			    unsigned long orig_msr);
+extern void tm_abort(uint8_t cause);
+extern void tm_save_sprs(struct thread_struct *thread);
+extern void tm_restore_sprs(struct thread_struct *thread);