From imp@bsdimp.com Sat Jan 9 16:45:38 2016 Date: Sat, 9 Jan 2016 16:45:34 -0500 From: Warner Losh To: monthly@freebsd.org Subject: pnp report (last one) Minimal kernel with PNP-based autoloading Warner Losh imp@freebsd.org

Work on automatically loading modules based on the plug and play data from devices that are scanned and found not to have a driver progresses. Digging this information out from the kernel modules, as well as tagging relevant bits of driver tables has been committed. PC Card, USB and some PCI devices now have these markings. This data is stored in a file that the kernel, boot loader and user land processes all have access to.

When complete, a user can run a minimal kernel (currently checked in as MINIMAL config). Devices necessary for booting will be loaded by loader(8). Other devices may be loaded there, or early in the boot (depending on which gives better performance). Users will still be able to run more "monolithic" configurations, as well as limit kernel modules as today, though without the convenience that automatic loading will provide. This work is ongoing.

Need to go through all the simplebus drivers and add this information there. Some additional minor simplebus functionality is needed. There is some work in progress for this. Need to go through all the PCI drivers and add this information to them. Unlike PC Card or USB, the PCI bus doesn't have a stylized table of PCI Ids, which each driver inventing its own method, so the semi-mechanical conversion done with PC Card and USB will not be possible. Instead, customized code for each one will be needed. Since a large number of them have their own device tables, the work will be primarily writing a description of the current table style. Run time parsing and loading is still needed.