[U-Boot] Getting started with SPL

[Heshsham Abdul Basit]

*HI, *


*OS:* petalinux <https://github.com/Xilinx/u-boot-xlnx/tree/master-next>

*Board:* Xilinx z702 evaluation
board<http://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC702-G.htm>
having
ARM Cortex A9 and FPGA on the zc700 SoC

* Background:* I observed that first message on the console comes after 1
second. It is the message from u-boot. Why this was happening? Because I
had to use a fsbl (first stage boot
loader)<http://blog.fakultaet-technik.de/development-with-zynq-part-3-build-boot-files/>
for
initialization of hardware. I suspected that it is this fsbl that is
consuming 1 second initializing useless hardware which I will not use at
all. in fact I am not going to use any fpga bitstream also.

So I am trying to boot my Linux image using uboot-SPL
method<http://www.denx.de/en/pub/Documents/Presentations/EWC2012_Roeder_Zundel_Fastboot.pdf>
bypassing
fsbl.

The main advantage I can get is perhaps fastest possible boot.

I found this<https://github.com/Xilinx/u-boot-xlnx/blob/master/doc/README.SPL>
(README.SPL) document
that explains how to work with SPL. However I have following question w.r.t
to the this passage in the document:

The building of SPL images can be with:
define CONFIG_SPL

Because SPL images normally have a different text base, one has to be
configured by defining CONFIG_SPL_TEXT_BASE. The linker script has to be
defined with CONFIG_SPL_LDSCRIPT.

Questions:

1- In which file I should define #define CONFIG_SPL and
CONFIG_SPL_TEXT_BASE?

2-Where is the linker script? Do I need to define CONFIG_SPL_LDSCRIPT in
the linker script ?
Source code of SPL enabled u-boot for xilinx board I am using is
this<https://github.com/Xilinx/u-boot-xlnx/tree/master-next>

This is the first time I am trying to play with SPL so kindly help me
proceed.

Thanks and regards,

HB