- 启动流程分析及各环节文件生成流程(ZedBoard为例)

4. SD卡文件内容二(BOOT.bin)
SDK会生成FSBL的elf文件，另外加上从XPS导出的System.bit，以及我们在第一篇文章中编译生成的u-boot.elf，就可以生成用来实现SD卡启动系统的完整Bootloader。

集齐u-boot.elf、system.bit和fsbl.elf就可以生成Image文件了，在SDK软件中点击Xilinx Tools→CreateBoot Image，然后选择3个文件，点击Create Image，生成文件，其中

u-boot.bin文件就是需要的u-boot image文件，将其重命名为BOOT.BIN后拷贝到SD卡中。

4.1. Elf文件(FSBL)
fsbl.elf文件需要在SDK软件中生成，首先新建工程，选择Xilinx C Project，然后选择Zynq FSBL，编译工程即可生成zynq_fsbl_0.elf文件。

4.2. System.bit文件
system.bit是PL部分的BIT文件，首先在ISE软件中新建工程，加入zynq系统，在EDK中配置ARM核及其外设，返回ISE生成TOP HDL Source，点击generate Programming File即可生

成Bit文件，然后点击Export Hardware Design To SDK with Bitstream进入下一步。

4.3. U-boot.elf文件(SSBL)
1. 首先Git下载Xilinx U-Boot代码

git clone git://git.xilinx.com/u-boot-xlnx.git

2. 配置u-boot，在上一篇博客中介绍了交叉编译环境的建立，此处可直接进行配置

cd u-boot-xlnx

make zynq_zed_config

3. 编译u-boot

Make

以上步骤完成之后会生成一个u-boot文件，将其另存为u-boot.elf文件，此文件在生成Bootimage文件时会使用到。

5. SD卡文件内容三(Device Tree Blob)
5.1. Xilinx官网方法
This how-to describes the process of compiling a device tree blob.
Build Device Tree Blob is a part of the Xilinx design flow described in Getting Started.

Task Dependencies (Pre-requisites)

· Fetch Sources(Device Tree Generator sources and Linux sources)

· Hardware Project

Input Files Required

· Hardware Project directory

· Linux source directory

Output Files Produced

· *.dts, *.dtb

Task Description

Creating a Device Tree Source (.dts) file

1 Open the hardware project in XPS.

Export the hardware system to SDK:
XPS Menu: Project > Export Hardware Design to SDK... > Export & Launch SDK

2 The Device Tree Generator Git repository needs to be downloaded as specified on the Fetch Sources page. In order for SDK to be able to import the Device

Tree Generator correctly, the downloaded Git repository device-tree/ will need to be placed under /bsp/ (create this directory hierarchy, if needed). The file hierarchy needs to look like:
/bsp/device-tree/data/device-tree_v2_1_0.mld
/bsp/device-tree/data/device-tree_v2_1_0.tcl

Add the BSP repository in SDK:
SDK Menu: Xilinx Tools > Repositories > New... () > OK

Create a Device Tree Board Support Package (BSP):
SDK Menu: File > New > Board Support Package > Board Support Package OS: device-tree > Finish

3 A BSP settings window will appear. This window can also be accessed by opening the Device Tree BSP's system.mss file and clicking 'Modify this BSP's Settings'.

Fill in the values as appropriate:

o The 'bootargs' parameter specifies the arguments passed to the kernel at boot time (kernel command line). ***

o The 'console device' parameter specifies which serial output device will be used. Select a value from the drop-down.

The .dts file is now located in //
/libsrc/device-tree_v*/xilinx.dts.