| Stephan Gerhold | 3f1d3e4 | 2020-01-04 18:45:19 +0100 | [diff] [blame] | 1 | ST-Ericsson U8500 Samsung "stemmy" board |
| 2 | ======================================== |
| 3 | |
| 4 | The "stemmy" board supports Samsung smartphones released with |
| 5 | the 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 | |
| 11 | and likely others as well (untested). |
| 12 | |
| 13 | At the moment, U-Boot is intended to be chain-loaded from |
| 14 | the original Samsung bootloader, not replacing it entirely. |
| 15 | |
| 16 | Installation |
| 17 | ------------ |
| 18 | |
| 19 | 1. Setup cross compiler, e.g. export CROSS_COMPILE=arm-none-eabi- |
| 20 | 2. make stemmy_defconfig |
| 21 | 3. make |
| 22 | |
| 23 | For newer devices (golden and skomer), the U-Boot binary has to be packed into |
| 24 | an Android boot image. janice boots the raw U-Boot binary from the boot partition. |
| 25 | |
| 26 | 4. Obtain mkbootimg, e.g. https://android.googlesource.com/platform/system/core/+/refs/tags/android-7.1.2_r37/mkbootimg/mkbootimg |
| 27 | 5. 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 | |
| 35 | 6. Enter Samsung download mode (press Power + Home + Volume Down) |
| 36 | 7. 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 | |
| 41 | 8. After reboot U-Boot prompt should appear via UART. |
| 42 | |
| 43 | UART |
| 44 | ---- |
| 45 | |
| 46 | UART is available through the micro USB port, similar to the Carkit standard. |
| 47 | With a ~619kOhm resistor between ID and GND, 1.8V RX/TX is available at D+/D-. |
| 48 | |
| 49 | Make sure to connect the UART cable *before* turning on the phone. |