ARM: at91: pm: Add sama5d2 backup mode

The sama5d2 has a mode were it is possible to cut power to the SoC while
keeping the RAM in self refresh.
Resuming from that mode needs support in the firmware/bootloader.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Wenyou Yang <wenyou.yang@atmel.com>
diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h
index fc0f7d0..d9c6612 100644
--- a/arch/arm/mach-at91/pm.h
+++ b/arch/arm/mach-at91/pm.h
@@ -22,6 +22,7 @@
 #define AT91_MEMCTRL_DDRSDR	2
 
 #define	AT91_PM_SLOW_CLOCK	0x01
+#define	AT91_PM_BACKUP		0x02
 
 #ifndef __ASSEMBLY__
 struct at91_pm_data {
@@ -30,6 +31,9 @@ struct at91_pm_data {
 	unsigned long uhp_udp_mask;
 	unsigned int memctrl;
 	unsigned int mode;
+	void __iomem *shdwc;
+	void __iomem *sfrbu;
+	unsigned int deepest_state;
 };
 #endif