1ST-Ericsson U8500 Samsung "stemmy" board
2========================================
3
4The "stemmy" board supports Samsung smartphones released with
5the ST-Ericsson NovaThor U8500 SoC, e.g.
6
7	- Samsung Galaxy S III mini (GT-I8190)	"golden"
8	- Samsung Galaxy S Advance (GT-I9070)	"janice"
9	- Samsung Galaxy Xcover 2 (GT-S7710)	"skomer"
10
11and likely others as well (untested).
12
13At the moment, U-Boot is intended to be chain-loaded from
14the original Samsung bootloader, not replacing it entirely.
15
16Installation
17------------
18
191. Setup cross compiler, e.g. export CROSS_COMPILE=arm-none-eabi-
202. make stemmy_defconfig
213. make
22
23For newer devices (golden and skomer), the U-Boot binary has to be packed into
24an Android boot image. janice boots the raw U-Boot binary from the boot partition.
25
264. Obtain mkbootimg, e.g. https://android.googlesource.com/platform/system/core/+/refs/tags/android-7.1.2_r37/mkbootimg/mkbootimg
275. mkbootimg \
28    --kernel=u-boot.bin \
29    --base=0x00000000 \
30    --kernel_offset=0x00100000 \
31    --ramdisk_offset=0x02000000 \
32    --tags_offset=0x00000100 \
33    --output=u-boot.img
34
356. Enter Samsung download mode (press Power + Home + Volume Down)
367. Flash U-Boot image to Android boot partition using Heimdall:
37     https://gitlab.com/BenjaminDobell/Heimdall
38
39   heimdall flash --Kernel u-boot.(bin|img)
40
418. After reboot U-Boot prompt should appear via UART.
42
43UART
44----
45
46UART is available through the micro USB port, similar to the Carkit standard.
47With a ~619kOhm resistor between ID and GND, 1.8V RX/TX is available at D+/D-.
48
49Make sure to connect the UART cable *before* turning on the phone.
50