I am compiling linux process as below.
but compile was failed, because there no meta-altera folder…on the github
Altera Opensource · GitHub link.
where is the meta-altera folder?
Are you guys maintaining this web???
I want to compile rootfs using this legacy method.
But Intel fpga SOC support is very poor…
So that’s why we can not win Xilinx zynq…
This page has the details about how to use meta-altera. Strange that the link is on github.com/kraj/meta-altera 
I went through the same pain when building yocto for my de10-nano and finally figured out a way to get debian working with it. Main benefit is you can use the cutting edge kernel and have a reasonably flexible general purpose linux OS on your device. I don’t know which board you are using, but if it’s cylcone V, many of the steps should be useable. Here is the link in case you find it useful: