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>

1 files 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 */