Hi Liu yong,
The document on the link https://community.nxp.com/docs/DOC-343242 was written by me, After I saw your questions, I re-downloaded android 9.0 source code according to steps in the document without any change.
I began to download it at 13:45 on November 2nd, and finishing download at 5:22 on November 4nd. The total download time is about 40 hours.
Several repo sync failed errors were encountered during the download process. Every time this error occurs, run the repo sync command and the download can continue. See below screenshot, please!
Below is android source code :
[Comment]
Chinese customers may not be able to download Android source code directly from Google, but Chinese customers have two ways to obtain Android source code, one is Tsinghua University image; the other is China University of science and technology mirror site. Therefore, if you think the image site of Tsinghua University is slow, you can try to use the mirror site of China University of science and technology. You can search the website of University of science and technology of China on the Internet, and then adjust the website according to that document.
In addtition, we have no way to provide full android 9.0 source code for you directly, but you can ask FAE of our distributor to provide more help for you.
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链接https://community.nxp.com/docs/doc-343242上的文档是我写的，看到你的问题后，我按照文档中的步骤重新下载了Android9.0源代码，没有任何变化。我于11月2日13:45开始下载，11月4日5:22完成下载。总下载时间约为40小时。
下载过程中遇到几个repo sync失败错误。每次出现此错误时，请运行repo sync命令，然后可以继续下载。请看下面的截图！
中国客户可能无法直接从谷歌下载Android源代码，但中国客户有两种获取Android源代码的方式，一种是清华大学镜像；另一种是中国科技大学镜像。因此，如果你认为清华大学的镜像站下载缓慢，可以尝试使用中国科技大学的镜像站。你可以在网上搜索中国科技大学的网站，然后根据该网址调整下载地址。
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另外，我们无法直接为您提供完整的android 9.0源代码，但是您可以向我们的经销商fae寻求更多帮助。
Have a nice day!
BR,
Weidong
