Hi Ken, In the LiveCD initrd I probe for modules needed to access CD/DVD ROMS (IDE, SATA), USB disks/sticks and network cards (in case of a diskless client). https://svn.iac.ethz.ch/pub/livecd/trunk/linux-live.sl/initrd/linuxrc https://svn.iac.ethz.ch/pub/livecd/trunk/linux-live.sl/initrd/liblinuxlive
The SATA part is very simple, I just load libata, ata_piix, ahci, sata_nv, sata_svw, sg, ... This seems to be good enough for most DVD/CD ROMS connected over SATA. Of course I would be interested in a more "intelligent" way to load the sata modules. Concerning the detection of the network card. I did it on older LiveCDs with a statically compiled lspci (running under busybox) and some grep commands looking in the file pcitable for the correct module. The static lspci is still available in https://svn.iac.ethz.ch/pub/livecd/trunk/linux-live.sl/initrd/static-binaries/ However, pcitable was always out of date and the modules could support more cards than listed in pcitable. Therefore I decided to do it with brute force. Now, I load a network module, check if I see an active link. If not, I unload the module again and load the next network module ... and so on. This is fast and works nicely. Cheers, Urs Mark Stodola wrote: > Ken, > > /proc/pci contains much of the info provided by lspci. For an initrd > script, you might want to consider looking at the linux-live scripts > used to build many of the livecds you find online (include the SL > flavor made by Urs). I believe if you look at Urs's livecd-trunk, you > will find linux-live.sl/initrd/liblinuxlive. This file has procedures > for probing all common modules for a certain type of support (e.g. > modprobe_usb_sata_modules). Brute force seems the standard way to > go. I've made livecds in several ways, and have not run into a > situation where I had to manually identify and probe modules for a > specific IDE or SATA controller. > > Are you doing something drastically different from the norm? > > Cheers, > Mark > > Ken Teh wrote: >> Hi Troy, >> >> I'm looking for something more basic. I'm trying to craft an init >> script for an initrd image to load appropriate drivers. Nothing >> fancy. Just the basics. Like what sort of hard drives are on the >> system. SATA or IDE? The SATA issue confuses me since there is a >> plethora of SATA drivers. Does the init script have to try each one >> to see if it finds a match or is there something in /proc or /sys >> that provides some identification? >> >> The only tool I have in my initrd image is busybox and it doesnt have >> an lspci equivalent. The /proc system contains a subdirectory that >> lists all devices on PCI but as bus.device files. I tried cat'ing >> the files but they are not ascii. I'm guessing it's possible to walk >> these files to extract the information I need. I can dig deeper but >> to save time, I'd ask if someone already knows the answer. >> >> Ken >> >> >> >> >> Troy Dawson wrote: >>> Mark Stodola wrote: >>>> I believe most of anaconda's "magic" comes from probing the PCI and >>>> USB bus for vendor and device IDs. If you dig into a driver (for >>>> example, e1000e), you will find a pcitable listing all of the IDs >>>> the driver supports. If you look in /lib/modules/<kernel>/ you >>>> will find a modules.pcimap and modules.usbmap among other bus types. >>>> >>>> Hope that helps. >>>> >>>> Cheers, >>>> Mark >>>> >>>> Ken Teh wrote: >>>>> How does a system determine the appropriate sata driver? >>>>> Specifically, how does anaconda figure out to write >>>>> >>>>> alias scsi_hostadapter ata_piix >>>>> >>>>> in my modprobe.conf and to bind it into my initrd image? >>>>> >>>>> I took apart boot.iso but didnt find anything "readable" that >>>>> indicated how this was determined. >>>>> >>>>> Thanks! >>>>> >>>>> Ken >>>>> >>>> >>>> >>> >>> Hi Ken, >>> On SL 5, alot of that data comes from hwdata, which is in the >>> /usr/share/hwdata directory. >>> The main ones people and programs look at is >>> pci.ids and usb.ids >>> But there are other files in there. >>> Troy >> > >
