rockchip: configs: mk808: change CONFIG_TPL_TEXT_BASE

Currently the Rockchip rk3066a u-boot-tpl.bin file needs
to add the characters "RK30", while the other SoCs replace
the first 4 bytes. Bring this in line with the rest by
lowering CONFIG_TPL_TEXT_BASE and update rockchip.rst
instructions.

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>

configs/mk808_defconfig

@@ -18,7 +18,7 @@ CONFIG_SPL_TEXT_BASE=0x60000000
 CONFIG_DM_RESET=y
 CONFIG_ROCKCHIP_RK3066=y
 # CONFIG_ROCKCHIP_STIMER is not set
-CONFIG_TPL_TEXT_BASE=0x10080C04
+CONFIG_TPL_TEXT_BASE=0x10080c00
 CONFIG_TPL_STACK=0x1008FFFF
 CONFIG_TARGET_MK808=y
 CONFIG_SPL_STACK_R_ADDR=0x70000000

doc/board/rockchip/rockchip.rst

@@ -390,9 +390,8 @@ Program with commands in a bash script ./flash.sh:
 
         #!/bin/sh
 
-        printf "RK30" > tplspl.bin
-        dd if=u-boot-tpl.bin >> tplspl.bin
-        truncate -s %2048 tplspl.bin
+        printf "RK30" | dd conv=notrunc bs=4 count=1 of=u-boot-tpl.bin
+        truncate -s %2048 u-boot-tpl.bin
         truncate -s %2048 u-boot-spl.bin
         ../tools/boot_merger --verbose config-flash.ini
         ../tools/upgrade_tool ul ./RK30xxLoader_uboot.bin
@@ -416,7 +415,7 @@ config-flash.ini:
         NUM=2
         LOADER1=FlashData
         LOADER2=FlashBoot
-        FlashData=tplspl.bin
+        FlashData=u-boot-tpl.bin
         FlashBoot=u-boot-spl.bin
         [OUTPUT]
         PATH=RK30xxLoader_uboot.bin