MIPS: Add hibernation support

[Ralf: SMP support requires CPU hotplugging which MIPS currently doesn't
support.  As implemented in this patch cache and tlb flushing will also be
invoked with interrupts disabled so smp_call_function() will blow up in
charming ways.  So limit to !SMP.]

Reviewed-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Yan Hua <yanh@lemote.com>
Reviewed-by: Arnaud Patard <apatard@mandriva.com>
Reviewed-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Wu Zhangjin <wuzj@lemote.com>
Signed-off-by: Hu Hongbing <huhb@lemote.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/power/cpu.c b/arch/mips/power/cpu.c
new file mode 100644
index 0000000..7995df4
--- /dev/null
+++ b/arch/mips/power/cpu.c
@@ -0,0 +1,43 @@
+/*
+ * Suspend support specific for mips.
+ *
+ * Licensed under the GPLv2
+ *
+ * Copyright (C) 2009 Lemote Inc. & Insititute of Computing Technology
+ * Author: Hu Hongbing <huhb@lemote.com>
+ *         Wu Zhangjin <wuzj@lemote.com>
+ */
+#include <asm/suspend.h>
+#include <asm/fpu.h>
+#include <asm/dsp.h>
+
+static u32 saved_status;
+struct pt_regs saved_regs;
+
+void save_processor_state(void)
+{
+	saved_status = read_c0_status();
+
+	if (is_fpu_owner())
+		save_fp(current);
+	if (cpu_has_dsp)
+		save_dsp(current);
+}
+
+void restore_processor_state(void)
+{
+	write_c0_status(saved_status);
+
+	if (is_fpu_owner())
+		restore_fp(current);
+	if (cpu_has_dsp)
+		restore_dsp(current);
+}
+
+int pfn_is_nosave(unsigned long pfn)
+{
+	unsigned long nosave_begin_pfn = PFN_DOWN(__pa(&__nosave_begin));
+	unsigned long nosave_end_pfn = PFN_UP(__pa(&__nosave_end));
+
+	return	(pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
+}