ARM: socfpga: support suspend to ram

Add code that requests that the sdr controller go into
self-refresh mode.  This code is run from ocram.

Suspend-to-RAM and EDAC support are mutually exclusive on
SOCFPGA.  If the EDAC is enabled, it will prevent the
platform from going into suspend.

Example of how to request to suspend to ram:
 $ echo enabled > \
/sys/devices/soc/ffc02000.serial0/tty/ttyS0/power/wakeup

 $ echo -n mem > /sys/power/state

Signed-off-by: Alan Tull <atull@opensource.altera.com>
Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c
index a154920b06ab..19643a756c48 100644
--- a/arch/arm/mach-socfpga/socfpga.c
+++ b/arch/arm/mach-socfpga/socfpga.c
@@ -1,5 +1,5 @@
 /*
- *  Copyright (C) 2012 Altera Corporation
+ *  Copyright (C) 2012-2015 Altera Corporation
  *
  * 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
@@ -29,6 +29,7 @@
 
 void __iomem *sys_manager_base_addr;
 void __iomem *rst_manager_base_addr;
+void __iomem *sdr_ctl_base_addr;
 unsigned long socfpga_cpu1start_addr;
 
 void __init socfpga_sysmgr_init(void)
@@ -49,6 +50,9 @@ void __init socfpga_sysmgr_init(void)
 
         np = of_find_compatible_node(NULL, NULL, "altr,rst-mgr");
         rst_manager_base_addr = of_iomap(np, 0);
+
+        np = of_find_compatible_node(NULL, NULL, "altr,sdr-ctl");
+        sdr_ctl_base_addr = of_iomap(np, 0);
 }
 
 static void __init socfpga_init_irq(void)