Ubuntu 15.10 Server; W: Possible missing firmware /lib/firmware/ast_dp501_fw.bin for module ast

Its annoying, but harmless. That is coming from the Aspeed VGA module from the IPMI on your server/workstation. It can be safely ignored for now. I took a quick look at the source code of the aspeed DRM driver. It is hardcoded at runtime to look for /lib/firmware/ast_dp501_fw.bin. This provides a way to update for firmware issues at runtime versus needing to be flashed onto the hardware.

Here is the lspci output showing the video card in question from my Asus Workstation which has the same "issue" as it were:

lspci |grep -i aspeed
 01:01.0 VGA compatible controller: ASPEED Technology, Inc. ASPEED Graphics Family (rev 10)

Aspeed's drivers and source for drivers are here (but you shouldn't need them from there unless you have a Windows server):

http://www.aspeedtech.com/support.php?fPath=24

Here is the Bug report: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1751613

Final(?) Update: I assume this particular error will be there forever since it's on End of Life hardware. The bug above remains in expired status since 2018-04-28.

Supermicro provide a Google Drive (lol) link to this file here: https://www.supermicro.com/support/faqs/faq.cfm?faq=26876 but I wouldn't use it unless a) you have a Supermicro board and b) you're having problems with the IPMI VGA controller (you're not).

Josip Medved proposed a solution in a post to avoid the warning:

sudo touch /lib/firmware/ast_dp501_fw.bin

It looks like an empty file is also safe and the warning will stop.