powerpc/85xx: add DOZE/NAP support for e500 core

The e500 core enter DOZE/NAP power-saving modes when the core go to
cpu_idle routine.

The power management default running mode is DOZE, If the user

echo 1 > /proc/sys/kernel/powersave-nap

the system will change to NAP running mode.

Signed-off-by: Dave Liu <daveliu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 47 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 7c2b65380658..c4268500e856 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -39,6 +39,7 @@
 #include <asm/thread_info.h>
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
+#include <asm/cache.h>
 #include "head_booke.h"
 
 /* As with the other PowerPC ports, it is expected that when code
@@ -1071,6 +1072,52 @@ _GLOBAL(set_context)
 	isync			/* Force context change */
 	blr
 
+_GLOBAL(flush_dcache_L1)
+	mfspr	r3,SPRN_L1CFG0
+
+	rlwinm	r5,r3,9,3	/* Extract cache block size */
+	twlgti	r5,1		/* Only 32 and 64 byte cache blocks
+				 * are currently defined.
+				 */
+	li	r4,32
+	subfic	r6,r5,2		/* r6 = log2(1KiB / cache block size) -
+				 *      log2(number of ways)
+				 */
+	slw	r5,r4,r5	/* r5 = cache block size */
+
+	rlwinm	r7,r3,0,0xff	/* Extract number of KiB in the cache */
+	mulli	r7,r7,13	/* An 8-way cache will require 13
+				 * loads per set.
+				 */
+	slw	r7,r7,r6
+
+	/* save off HID0 and set DCFA */
+	mfspr	r8,SPRN_HID0
+	ori	r9,r8,HID0_DCFA@l
+	mtspr	SPRN_HID0,r9
+	isync
+
+	lis	r4,KERNELBASE@h
+	mtctr	r7
+
+1:	lwz	r3,0(r4)	/* Load... */
+	add	r4,r4,r5
+	bdnz	1b
+
+	msync
+	lis	r4,KERNELBASE@h
+	mtctr	r7
+
+1:	dcbf	0,r4		/* ...and flush. */
+	add	r4,r4,r5
+	bdnz	1b
+	
+	/* restore HID0 */
+	mtspr	SPRN_HID0,r8
+	isync
+
+	blr
+
 /*
  * We put a few things here that have to be page-aligned. This stuff
  * goes at the beginning of the data segment, which is page-aligned.