U-Boot for the Samsung N1 device family

DISCLAMER! Moving your Samsung Galaxy R (GT-I9103) or Samsung Captivate Glide (SGH-i927) to use U-Boot assumes replacement of the sboot. Vendor android firmwares will no longer be able to run on the device. This replacement IS reversible.

Quick Start

  • Build U-Boot

  • Boot

Build U-Boot

Device support is implemented by applying config fragment to a generic board defconfig. Generic board defconfig is suitable for Samsung Galaxy R (GT-I9103) while Samsung Captivate Glide (SGH-i927) support is provided by applying bose.config fragment.

$ export CROSS_COMPILE=arm-none-eabi-
$ make n1_defconfig bose.config # For Captivate Glide
$ make

After the build succeeds, you will obtain the final u-boot-dtb-tegra.bin image, ready for further processing.

Boot

Currently, U-Boot can be preloaded into RAM via the NvFlash. To enter RCM protocol use home and volume up for Galaxy R and volume down and volume up Captivate Glide key combination plus plugging usb in. The host PC should recognize an APX device.

Built U-Boot u-boot-dtb-tegra.bin can be loaded from fusee-tools directory with

$ ./utils/nvflash_t20 --setbct --bct ./bct/i927.bct --configfile ./utils/flash.cfg --bl u-boot-dtb-tegra.bin --sbk (in form of 0xABCDABCD 4 times) --sync # For Captivate Glide

To boot Linux, U-Boot will look for an extlinux.conf on MicroSD and then on eMMC. Additionally, if the Volume Down button is pressed while loading, the device will enter bootmenu. Bootmenu contains entries to mount MicroSD and eMMC as mass storage, fastboot, reboot, reboot RCM and poweroff.