Booting from firmware RAID

Ilya Kazakevich kazakevichilya at
Wed Mar 16 18:05:47 UTC 2011

My boot0 freezes. I found discussion where guy told that extipl works fine
but boot0 not because extipl uses LBA instead of CHS and some raids do not
support CHS.
It is new to me that BIOS allows LBA but I will try extipl now.

On Wed, Mar 16, 2011 at 5:11 PM, b. f. <bf1783 at> wrote:

> > This is probably more PC-specific than freebsd-specific question. I have
> > intel firmware raid. OS needs drivers to work with it. FreeBSD sees it as
> > ar0, so it has drivers.
> > But I want my OS to be installed on this drive and boot from it. It is
> not
> > good idea, but I really want to do it:)
> > Is it possible?
> >
> > boot0 and boot1 both work with HDD via BIOS interrupts and CHS, right?
> So,
> > how do they know how to access RAID? They has no drivers.
> > Or BIOS supports interrupts to access RAID with out of drivers? If so --
> > what for drivers are needed? To access drive via ATA interface?
> >
> > Is it possible to boot freebsd from "firmware raid"?
> Sometimes: it depends on the firmware, and your bios.  I had a add-in
> PCIe SATA RAID controller based on a Marvell SE9128 chipset, and using
> a Marvell firmware.  The bios and the FreeBSD 9-CURRENT bootloader
> were able to boot from a JBOD drive attached to the controller, up
> until the point where the ahci driver tried to take control of the
> drive.  Then the Marvell firmware presented a fictitious configuration
> to the ahci driver and returned invalid device signatures, so the boot
> process failed.  On the same machine, however, I was able to boot
> without problems from a JBOD drive attached to a PCI-X SATA RAID
> controller based on the Silicon Image SiI3124 chipset, using a Silicon
> Image firmware.
> b.

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