File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/mips/include/asm/pm-cps.h b/arch/mips/include/asm/pm-cps.h
new file mode 100644
index 0000000..625eda5
--- /dev/null
+++ b/arch/mips/include/asm/pm-cps.h
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2014 Imagination Technologies
+ * Author: Paul Burton <paul.burton@imgtec.com>
+ *
+ * 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.
+ */
+
+#ifndef __MIPS_ASM_PM_CPS_H__
+#define __MIPS_ASM_PM_CPS_H__
+
+/*
+ * The CM & CPC can only handle coherence & power control on a per-core basis,
+ * thus in an MT system the VPEs within each core are coupled and can only
+ * enter or exit states requiring CM or CPC assistance in unison.
+ */
+#ifdef CONFIG_MIPS_MT
+# define coupled_coherence cpu_has_mipsmt
+#else
+# define coupled_coherence 0
+#endif
+
+/* Enumeration of possible PM states */
+enum cps_pm_state {
+	CPS_PM_NC_WAIT,		/* MIPS wait instruction, non-coherent */
+	CPS_PM_CLOCK_GATED,	/* Core clock gated */
+	CPS_PM_POWER_GATED,	/* Core power gated */
+	CPS_PM_STATE_COUNT,
+};
+
+/**
+ * cps_pm_support_state - determine whether the system supports a PM state
+ * @state: the state to test for support
+ *
+ * Returns true if the system supports the given state, otherwise false.
+ */
+extern bool cps_pm_support_state(enum cps_pm_state state);
+
+/**
+ * cps_pm_enter_state - enter a PM state
+ * @state: the state to enter
+ *
+ * Enter the given PM state. If coupled_coherence is non-zero then it is
+ * expected that this function be called at approximately the same time on
+ * each coupled CPU. Returns 0 on successful entry & exit, otherwise -errno.
+ */
+extern int cps_pm_enter_state(enum cps_pm_state state);
+
+#endif /* __MIPS_ASM_PM_CPS_H__ */