How to boot baremetal code from sd card

Hello,

booting own baremetal code from SD Card or other Flash device is quite simple.

All you need is a preloader, which is started first on bootup.

the preloader initializes the basic functions of your HPS and loads i.e. code from FLASH or SD-Card into the SDRAM.

The code that is loaded can be either an U-Boot, that loads your Linux image or it could be directly an baremetal application.

A tutorial for the preloader can be found here:

http://www.rocketboards.org/foswiki/documentation/gsrdpreloader#generating_the_preloader

if you want to store your baremetal application on a FAT partition, you have to enable some settings for the preloader:

http://www.rocketboards.org/foswiki/documentation/preloaderubootcustomization#preloaderubootfatpartition

The image for the baremetal application, stored on the SD-CARD have to be created with a command like this:

mkimage -A arm -O u-boot -T standalone -C none -a 0x01000000 -e 0x01000000 -n "Name_Of_Your_Application" -d baremetal.bin baremetal.img

The mkimage tool can be found in the source folder of the generated preloader.

That's all. If you've any more questions, just ask.