[SOLVED] What are the ways to set driver parameters?

linuxbird · 12-03-2016, 12:37 PM

I just need a pointer or two in setting driver parameters (for the AHCI driver).

It can be done at boot time, but can I do it after boot? And if so, how?

Slackware 14.0

Richard Cranium · 12-03-2016, 01:04 PM

Unload the module and reload with the parameters on the command line is one way. You can also set configuration in /etc/modprobe.d/ configuration files.

"man modprobe" should tell you want you need to know.

EDIT: that only works for stuff that isn't built into the kernel.

linuxbird · 12-03-2016, 01:15 PM

The driver is already in the kernel, so I infer that mod will not work.

It looks like my option is to do a lilo change and reboot. I can live with that, I was just trying to understand my options.

Richard Cranium · 12-03-2016, 02:44 PM

Well, there might be places in the /proc filesystem where you can write config changes.

EDIT: What parameters are you setting, anyways?

Didier Spaier · 12-03-2016, 03:00 PM

From /usr/src/linux/Documentation/kernel-parameters.txt:

Quote:

Parameters for modules which are built into the kernel need to be
specified on the kernel command line. modprobe looks through the
kernel command line (/proc/cmdline) and collects module parameters
when it loads a module, so the kernel command line can be used for
loadable modules too.

dugan · 12-03-2016, 03:38 PM

Quote:

Originally Posted by Richard Cranium

Well, there might be places in the /proc filesystem where you can write config changes.

Or the /sys filesystem.

Obviously, you'd get a better answer when you say what the setting is.

linuxbird · 12-03-2016, 06:37 PM

I ended up setting it through the LILO entry and rebooting. The driver was compiled with the kernel, and I wanted to try a couple different settings, as well as experiment with related ones.

In the end, there were a couple of entries in the LILO.conf so that I could pick the one I wanted.

Oh, the parameter? I guess it's not fair to ask and have people guessing. ahci.marvell_enable=1 and =0

Richard Cranium · 12-03-2016, 11:36 PM

This might work when run as root...

echo "1" >/sys/module/ahci/parameters/marvell_enable