I am using prototype board based on i.mx28.
power supply is configured for VDD5V only. Based on the Application note AN4199: "Using i.MX28 power management unit and battery charger" on Pg#20.
To enable the VDD5V only, I am referring Patch L2.6.35_10.12_SDK_5V_SUPPLY_PATCH.tar.gz at freescale website. I have applied the patch to bootlet code imx-bootlets-src-10.12.01.tar.gz.
I followed below steps to boot the u-boot:
1) Copied the u-boot under imx-bootlets-src directory after untaring and patching the source. Prototype uses the same Winbond RAM so no changes.
2) Export Toolchain path and added "BOARD = iMX28_EVK" to the Makefile
3) Performed "make" to create imx28_ivt_uboot.sb
4) Boot the prototype with USB boot option
5) load the image via command "sb_loader.exe -f imx28_ivt_uboot.sb"
Output on console:
PowerPrep start initialize power...
Configured for 5v only power source. Battery powered operation disabled.
Apr 3 201414:02:29
memory type is DDR2
Wait for ddr ready 1power 0x00820616
start change cpu freq
start test memory accress
finish simple test
U-Boot 2013.04-00053-g08868db-dirty (Mar 31 2014 - 15:23:12)
CPU: Freescale i.MX28 rev1.2 at 454 MHz
DRAM: 61 Bytes
Any suggestions why U-boot fails to find the boot mode and fails to execute? Is there any way I can test the same code on EVK, as looking to the EVK schematics, it seems that it has implemented DCDC_BATT source hardware configuration?