1 files changed, 86 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/idle_book3e.S b/arch/powerpc/kernel/idle_book3e.S
new file mode 100644
index 000000000000..16c002d6bdf1
--- /dev/null
+++ b/arch/powerpc/kernel/idle_book3e.S
@@ -0,0 +1,86 @@
+/*
+ * Copyright 2010 IBM Corp, Benjamin Herrenschmidt <benh@kernel.crashing.org>
+ *
+ * Generic idle routine for Book3E processors
+ *
+ * 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.
+ */
+
+#include <linux/threads.h>
+#include <asm/reg.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/ppc-opcode.h>
+#include <asm/processor.h>
+#include <asm/thread_info.h>
+
+/* 64-bit version only for now */
+#ifdef CONFIG_PPC64
+
+_GLOBAL(book3e_idle)
+        /* Save LR for later */
+        mflr    r0
+        std     r0,16(r1)
+
+        /* Hard disable interrupts */
+        wrteei  0
+
+        /* Now check if an interrupt came in while we were soft disabled
+         * since we may otherwise lose it (doorbells etc...). We know
+         * that since PACAHARDIRQEN will have been cleared in that case.
+         */
+        lbz     r3,PACAHARDIRQEN(r13)
+        cmpwi   cr0,r3,0
+        beqlr
+
+        /* Now we are going to mark ourselves as soft and hard enables in
+         * order to be able to take interrupts while asleep. We inform lockdep
+         * of that. We don't actually turn interrupts on just yet tho.
+         */
+#ifdef CONFIG_TRACE_IRQFLAGS
+        stdu    r1,-128(r1)
+        bl      .trace_hardirqs_on
+#endif
+        li      r0,1
+        stb     r0,PACASOFTIRQEN(r13)
+        stb     r0,PACAHARDIRQEN(r13)
+        
+        /* Interrupts will make use return to LR, so get something we want
+         * in there
+         */
+        bl      1f
+
+        /* Hard disable interrupts again */
+        wrteei  0
+
+        /* Mark them off again in the PACA as well */
+        li      r0,0
+        stb     r0,PACASOFTIRQEN(r13)
+        stb     r0,PACAHARDIRQEN(r13)
+
+        /* Tell lockdep about it */
+#ifdef CONFIG_TRACE_IRQFLAGS
+        bl      .trace_hardirqs_off
+        addi    r1,r1,128
+#endif
+        ld      r0,16(r1)
+        mtlr    r0
+        blr
+
+1:      /* Let's set the _TLF_NAPPING flag so interrupts make us return
+         * to the right spot
+        */
+        clrrdi  r11,r1,THREAD_SHIFT
+        ld      r10,TI_LOCAL_FLAGS(r11)
+        ori     r10,r10,_TLF_NAPPING
+        std     r10,TI_LOCAL_FLAGS(r11)
+
+        /* We can now re-enable hard interrupts and go to sleep */
+        wrteei  1
+1:      PPC_WAIT(0)
+        b       1b
+
+#endif /* CONFIG_PPC64 */