rockchip: add CONFIG_IRAM_BASE for all SoCs

Rockchip SoCs have internal sram for bootrom data area and for
sdram init program space. Introduce the base address in case
we need to use it.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/include/configs/rk3368_common.h b/include/configs/rk3368_common.h
index 1a859a7..340413d 100644
--- a/include/configs/rk3368_common.h
+++ b/include/configs/rk3368_common.h
@@ -23,6 +23,8 @@
 #define CONFIG_ROCKCHIP_STIMER_BASE	0xff830020
 #define COUNTER_FREQUENCY		24000000
 
+#define CONFIG_IRAM_BASE		0xff8c0000
+
 #define CONFIG_SYS_INIT_SP_ADDR		0x00300000
 #define CONFIG_SYS_LOAD_ADDR		0x00280000