Compiling uboot

Steps to build uboot
1. Clone the repository by
```
git clone -b sunxi
https://github.com/androportal/uboot-allwinner.git
```
2. cd into uboot-allwinner
```
cd uboot-allwinner
```
3. To compile uboot download and install Sourcery CodeBench Lite Edition, then issue:
```
make a13_olinuxino CROSS_COMPILE=arm-none-linux-gnueabi-
```
4. After successful compilation u-boot.bin will be available at root of the directory and sunxi-spl.bin will be in spl directory
Installing uboot on SDcard
1. Insert sdcard in card reader or MMC reader available in laptops/netbooks
2. Backup all your sdcard data, and issue the following commands carefully, replace X in /dev/sdX with suitable letter(a lower case alphabet) alloted for your sdcard, remember X will never be a if you have a hard disk installed, so keep in mind it must be something like /dev/sdb or /dev/sdc etc. Please check twice and if you are still unsure leave this README right now otherwise you may end up with non bootable machine
```
sudo fdisk -u=sectors /dev/sdX
```
3. Now from same uboot-allwinner directory issue these commands, again replace X with suitable value, now to burn sunxi-spl.bin to sdcard issue
```
sudo dd if=spl/sunxi-spl.bin of=/dev/sdX bs=1024 seek=8
```
  Similarly to burn u-boot.in issue
```
sudo dd if=u-boot.bin of=/dev/sdX bs=1024 seek=32
```
  At this point we have a bootable sdcard readly. Get kernel and rootfs to make a usuable Linux for your tablet.

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