1 files changed, 73 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/idle_power4.S b/arch/powerpc/kernel/idle_power4.S
new file mode 100644
index 000000000..f57a19348
--- /dev/null
+++ b/arch/powerpc/kernel/idle_power4.S
@@ -0,0 +1,73 @@
+/*
+ *  This file contains the power_save function for 970-family CPUs.
+ *
+ *  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/processor.h>
+#include <asm/page.h>
+#include <asm/cputable.h>
+#include <asm/thread_info.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/irqflags.h>
+
+#undef DEBUG
+
+	.text
+
+_GLOBAL(power4_idle)
+BEGIN_FTR_SECTION
+	blr
+END_FTR_SECTION_IFCLR(CPU_FTR_CAN_NAP)
+	/* Now check if user or arch enabled NAP mode */
+	LOAD_REG_ADDRBASE(r3,powersave_nap)
+	lwz	r4,ADDROFF(powersave_nap)(r3)
+	cmpwi	0,r4,0
+	beqlr
+
+	/* Hard disable interrupts */
+	mfmsr	r7
+	rldicl	r0,r7,48,1
+	rotldi	r0,r0,16
+	mtmsrd	r0,1
+
+	/* Check if something happened while soft-disabled */
+	lbz	r0,PACAIRQHAPPENED(r13)
+	cmpwi	cr0,r0,0
+	bnelr
+
+	/* Soft-enable interrupts */
+#ifdef CONFIG_TRACE_IRQFLAGS
+	mflr	r0
+	std	r0,16(r1)
+	stdu    r1,-128(r1)
+	bl	trace_hardirqs_on
+	addi    r1,r1,128
+	ld	r0,16(r1)
+	mtlr	r0
+	mfmsr	r7
+#endif /* CONFIG_TRACE_IRQFLAGS */
+
+	li	r0,1
+	stb	r0,PACASOFTIRQEN(r13)	/* we'll hard-enable shortly */
+BEGIN_FTR_SECTION
+	DSSALL
+	sync
+END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
+	CURRENT_THREAD_INFO(r9, r1)
+	ld	r8,TI_LOCAL_FLAGS(r9)	/* set napping bit */
+	ori	r8,r8,_TLF_NAPPING	/* so when we take an exception */
+	std	r8,TI_LOCAL_FLAGS(r9)	/* it will return to our caller */
+	ori	r7,r7,MSR_EE
+	oris	r7,r7,MSR_POW@h
+1:	sync
+	isync
+	mtmsrd	r7
+	isync
+	b	1b
+