From 237674e050ae8ea40a432412df6c15d60b7ae8a6 Mon Sep 17 00:00:00 2001
From: Magnus Damm <damm@igel.co.jp>
Date: Sat, 15 Aug 2009 02:53:42 +0000
Subject: [PATCH] sh: sh7724 ddr self-refresh changes

This patch updates the SuperH Mobile sleep assembly code with
support for DBSC memory controller found in the sh7724 processor.

Without this fix the memory hooked up to the sh7724 processor
will never enter self-refresh mode before suspending to ram. The
effect of this is that the memory contents most likeley will be
lost upon resume which may or may not be what you want.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
---
 arch/sh/kernel/cpu/shmobile/sleep.S | 70 ++++++++++++++++++++++++++++-
 1 file changed, 68 insertions(+), 2 deletions(-)

diff --git a/arch/sh/kernel/cpu/shmobile/sleep.S b/arch/sh/kernel/cpu/shmobile/sleep.S
index 5d888ef53d82..baf2d7d46b05 100644
--- a/arch/sh/kernel/cpu/shmobile/sleep.S
+++ b/arch/sh/kernel/cpu/shmobile/sleep.S
@@ -26,8 +26,30 @@ ENTRY(sh_mobile_standby)
 
 	tst	#SUSP_SH_SF, r0
 	bt	skip_set_sf
+#ifdef CONFIG_CPU_SUBTYPE_SH7724
+	/* DBSC: put memory in self-refresh mode */
 
-	/* SDRAM: disable power down and put in self-refresh mode */
+	mov.l	dben_reg, r4
+	mov.l	dben_data0, r1
+	mov.l	r1, @r4
+
+	mov.l	dbrfpdn0_reg, r4
+	mov.l	dbrfpdn0_data0, r1
+	mov.l	r1, @r4
+
+	mov.l	dbcmdcnt_reg, r4
+	mov.l	dbcmdcnt_data0, r1
+	mov.l	r1, @r4
+
+	mov.l	dbcmdcnt_reg, r4
+	mov.l	dbcmdcnt_data1, r1
+	mov.l	r1, @r4
+
+	mov.l	dbrfpdn0_reg, r4
+	mov.l	dbrfpdn0_data1, r1
+	mov.l	r1, @r4
+#else
+	/* SBSC: disable power down and put in self-refresh mode */
 	mov.l	1f, r4
 	mov.l	2f, r1
 	mov.l	@r4, r2
@@ -35,6 +57,7 @@ ENTRY(sh_mobile_standby)
 	mov.l   3f, r3
 	and	r3, r2
 	mov.l	r2, @r4
+#endif
 
 skip_set_sf:
 	tst	#SUSP_SH_SLEEP, r0
@@ -84,7 +107,36 @@ done_sleep:
 	tst	#SUSP_SH_SF, r0
 	bt	skip_restore_sf
 
-	/* SDRAM: set auto-refresh mode */
+#ifdef CONFIG_CPU_SUBTYPE_SH7724
+	/* DBSC: put memory in auto-refresh mode */
+
+	mov.l	dbrfpdn0_reg, r4
+	mov.l	dbrfpdn0_data0, r1
+	mov.l	r1, @r4
+
+	/* sleep 140 ns */
+	nop
+	nop
+	nop
+	nop
+
+	mov.l	dbcmdcnt_reg, r4
+	mov.l	dbcmdcnt_data0, r1
+	mov.l	r1, @r4
+
+	mov.l	dbcmdcnt_reg, r4
+	mov.l	dbcmdcnt_data1, r1
+	mov.l	r1, @r4
+
+	mov.l	dben_reg, r4
+	mov.l	dben_data1, r1
+	mov.l	r1, @r4
+
+	mov.l	dbrfpdn0_reg, r4
+	mov.l	dbrfpdn0_data2, r1
+	mov.l	r1, @r4
+#else
+	/* SBSC: set auto-refresh mode */
 	mov.l	1f, r4
 	mov.l	@r4, r2
 	mov.l   4f, r3
@@ -98,15 +150,29 @@ done_sleep:
 	add	r4, r3
 	or	r2, r3
 	mov.l	r3, @r1
+#endif
 skip_restore_sf:
 	rts
 	 nop
 
 	.balign 4
+#ifdef CONFIG_CPU_SUBTYPE_SH7724
+dben_reg:	.long	0xfd000010 /* DBEN */
+dben_data0:	.long	0
+dben_data1:	.long	1
+dbrfpdn0_reg:	.long	0xfd000040 /* DBRFPDN0 */
+dbrfpdn0_data0:	.long	0
+dbrfpdn0_data1:	.long	1
+dbrfpdn0_data2:	.long	0x00010000
+dbcmdcnt_reg:	.long	0xfd000014 /* DBCMDCNT */
+dbcmdcnt_data0:	.long	2
+dbcmdcnt_data1:	.long	4
+#else
 1:	.long	0xfe400008 /* SDCR0 */
 2:	.long	0x00000400
 3:	.long	0xffff7fff
 4:	.long	0xfffffbff
+#endif
 5:	.long	0xa4150020 /* STBCR */
 6:	.long   0xfe40001c /* RTCOR */
 7:	.long   0xfe400018 /* RTCNT */
-- 
2.30.2