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diff --git a/bsps/powerpc/shared/start/ppc_idle.c b/bsps/powerpc/shared/start/ppc_idle.c
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+/*
+ *  ppc_idle.c
+ *
+ * Authorship
+ * ----------
+ * This software was created by
+ *     Till Straumann <strauman@slac.stanford.edu>, 2010,
+ * 	   Stanford Linear Accelerator Center, Stanford University.
+ *
+ * Acknowledgement of sponsorship
+ * ------------------------------
+ * This software was produced by
+ *     the Stanford Linear Accelerator Center, Stanford University,
+ * 	   under Contract DE-AC03-76SFO0515 with the Department of Energy.
+ *
+ * Government disclaimer of liability
+ * ----------------------------------
+ * Neither the United States nor the United States Department of Energy,
+ * nor any of their employees, makes any warranty, express or implied, or
+ * assumes any legal liability or responsibility for the accuracy,
+ * completeness, or usefulness of any data, apparatus, product, or process
+ * disclosed, or represents that its use would not infringe privately owned
+ * rights.
+ *
+ * Stanford disclaimer of liability
+ * --------------------------------
+ * Stanford University makes no representations or warranties, express or
+ * implied, nor assumes any liability for the use of this software.
+ *
+ * Stanford disclaimer of copyright
+ * --------------------------------
+ * Stanford University, owner of the copyright, hereby disclaims its
+ * copyright and all other rights in this software.  Hence, anyone may
+ * freely use it for any purpose without restriction.
+ *
+ * Maintenance of notices
+ * ----------------------
+ * In the interest of clarity regarding the origin and status of this
+ * SLAC software, this and all the preceding Stanford University notices
+ * are to remain affixed to any copy or derivative of this software made
+ * or distributed by the recipient and are to be affixed to any copy of
+ * software made or distributed by the recipient that contains a copy or
+ * derivative of this software.
+ *
+ * ------------------ SLAC Software Notices, Set 4 OTT.002a, 2004 FEB 03
+ */
+#include <bsp.h>
+#include <stdint.h>
+
+#ifdef BSP_IDLE_TASK_BODY
+
+/* Provide an idle-task body which switches the
+ * CPU into power-save mode when idle. Any exception
+ * (including an interrupt/external-exception)
+ * wakes it up.
+ *
+ * IIRC - this cannot be used on real hardware due
+ *        to errata on many chips which is a real
+ *        pity. However, when used under qemu it
+ *        saves host-CPU cycles.
+ *        While qemu-0.12.4 needed to be patched
+ *        (would otherwise hang because an exception
+ *        didn't clear MSR_POW) qemu-0.14.1 seems
+ *        to work fine.
+ */
+
+#include <rtems/powerpc/registers.h>
+#include <libcpu/cpuIdent.h>
+#include <libcpu/spr.h>
+
+SPR_RW(HID0)
+
+void *
+bsp_ppc_idle_task_body(uintptr_t ignored)
+{
+uint32_t msr;
+
+	switch ( current_ppc_cpu ) {
+
+		case PPC_7400:
+		case PPC_7455:
+		case PPC_7457:
+			/* Must enable NAP mode in HID0 for MSR_POW to work */
+			_write_HID0( _read_HID0() | HID0_NAP );
+		break;
+
+		default:
+		break;
+	}
+
+	for ( ;; ) {
+		_CPU_MSR_GET(msr);
+		msr |= MSR_POW;
+		asm volatile(
+				"1: sync       \n"
+				"	mtmsr %0   \n"
+				"   isync      \n"
+				"   b 1b       \n"
+				::"r"(msr)
+				);
+	}
+
+	return 0;
+}
+
+#endif