Friendly zeropi uboot, kernel compilation,

I tried to compile it before uboot  After success , Bought zeropi  The board finally arrived , intermittent , Finally compiled and ran successfully ,

although zeropi wiki  It is directly provided on windos  Completion under img  and   Burning tools , It can be done with one click .

But as a beginner linux In terms of Meng Xin , It's still necessary to toss about , In this tossing process, I also learned a lot of knowledge , Process twists and turns record sorting ,

The main process reference is wiki:http://wiki.friendlyarm.com/wiki/index.php/Building_U-boot_and_Linux_for_H5/H3/H2%2B/zh

However, there is still a missing link in the process of the above tutorial , Root directory creation .

One 、uboot  compile

uboot  yes git  Branch version downloaded from ,

Downloaded nearly a dozen times, and finally successfully downloaded once ：https://github.com/friendlyarm/u-boot.git -b sunxi-v2017.x --depth 1

With the previous exercise , So there is no big problem , Pass smoothly all the way .

Two 、Linux compile

linux4.14 edition   Originally, I was going to download git  Upper , But this has also been downloaded more than a dozen times without success , Just give up ,

Later, I found a close one on the Internet 4.11 Use the version .

https://www.cnblogs.com/edan/p/9330708.html

meanwhile linux Part of the compilation also refers to this link . After all,  allwiner  Of bsp  It's also a smooth journey

3、 ... and 、busybox  compile

In limine , Also for convenience , I found a resource to download casually on the Internet , But the compilation is not a hint :undefined reference to `stime'

Baidu explained the reasons and solutions :https://blog.csdn.net/o_alpha/article/details/113487031

Then I went to the official website to get the latest https://busybox.net/downloads/

Finally, I finally compiled .

Four 、 Record and solve the problems encountered

When everything is ready, burn , Power on and run , Various problems follow :

uboot  Stage   The board can correctly identify :zeropi  But the device tree file shows  sun8i-h3-nanopi-m1-pluse  Of ,

At the same time, I didn't know at first  uboot  Also set , Direct hint   Unrecognized file system , Forget the screenshot , Probably :unrecognized fs type

To configure  bootcmd  and  bootargs  After that, I finally went on , here we are Starting kernel  Then there is no more .

I searched the Internet for answers , Also at the same time uboot  Stage jump in  linux  The stage is also understood , And this Starting kernel  Should be uboot  The last output ,

People's questions on the Internet are in the back   Also with  uncom....  What decompression image  Mirror image   What prompt , It's different from mine , My picture above has prompted  zImage  also   Device tree file   Has read .

Later, when I learned about the device tree file , I really found a problem , that 4.11 bsp Linux  In folder sun8i-h3-nanopi-m1-pluse Device tree   and  zeropi It's totally different .

zeropi wiki  Electrical schematic diagram of   http://wiki.friendlyarm.com/wiki/images/7/71/ZeroPi_20190731_Schematic.pdf

state led  Of IO mouth   It's not right .....

Later, I thought that since uboot  Medium device tree file identification sun8i-h3-nanopi-m1-pluse, Is that  uboot  Device tree file in   It should be available , and  dtb  Is the final binary , So it should be able to be used directly .

Follow this idea to directly replace   Device tree file , Unexpectedly, he really continued to run .

But in the end, I made a mistake ：end Kernel panic  .... No working init found ... At first, I only saw the last error prompt , I didn't want to look back ,

Find it directly from the error prompt :No working init found  But few of the same problems , Looked around a lot , However, the general positioning is related to the root file system , I also learned about a wave root file information by the way .

It's also a devil's errand , When turning up the print information of the kernel , Suddenly I saw mmc2  There are some problems here ：waiting for root device /dev/mmcblk2p1

Partition recognition is p1  and p2  however p1  Kernel image and device tree file partition , The file area is   Zoning is p2

So reset  bootargs  Parameters , Finally solved . 

But there are new problems ,couldn’t execute it （error -8） I searched the Internet ,

There are two main solutions , There are also permissions elf  Binary file format   atypism , But it's useless for the author to try .

But from the error prompt ： Documents exist , Combine the above sentence runaway loop modprobe  binfmt-464c  see   It should be related to binary format .

Later, I found the reason in this ：https://www.freesion.com/article/44611148946/

Recompile to solve , Then I finally entered the console , everything ok, Tested it  usb  mount , Finally, it's successful