rockchip: rk3368: spl: add memory layout for TPL and SPL

For the RK3368, we use a multi-stage boot-process consisting of the
following:
  1.  TPL: initalises DRAM, returns to boot-ROM (which then loads
           the next stage and transfers control to it)
  2.  SPL: a full-features SPL stage including OF_CONTROL and FIT
           image loading, which fetches the ATF, DTB and full U-Boot
	   and then transfers control to the ATF (using the BL31
	   parameter block to indicate the location of BL33/U-Boot)
  3.  ATF: sets up the secure world and exits to BL33 (i.e. a full
           U-Boot) in the normal world
  4.  full U-Boot

TPL/SPL and the full U-Boot are built from this tree and need to
run from distinct text addresses and with distinct initial stack
pointer addresses.

This commit sets up the configuration to run:
  -  TPL from the SRAM at 0xff8c0000 (note that the first 0x1000
     	 are reserved for use by the boot-ROM and contain the SP
	 when the TPL is entered)
  -  SPL from DRAM at 0x0
  -  U-Boot from DRAM at 0x200000

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

include/configs/rk3368_common.h

@@ -29,6 +29,17 @@
 #define CONFIG_SYS_INIT_SP_ADDR		0x00300000
 #define CONFIG_SYS_LOAD_ADDR		0x00280000
 
+#define CONFIG_SPL_TEXT_BASE            0x00000000
+#define CONFIG_SPL_MAX_SIZE             0x40000
+#define CONFIG_SPL_BSS_START_ADDR       0x400000
+#define CONFIG_SPL_BSS_MAX_SIZE         0x20000
+
+#define CONFIG_TPL_LDSCRIPT \
+	  "arch/arm/mach-rockchip/rk3368/u-boot-tpl.lds"
+#define CONFIG_TPL_TEXT_BASE		0xff8c1000
+#define CONFIG_TPL_MAX_SIZE		0x7000
+#define CONFIG_TPL_STACK		0xff8cffff
+
 #define CONFIG_BOUNCE_BUFFER
 
 #ifndef CONFIG_SPL_BUILD