Re: [PATCH] sata_mv: Fix broken Marvell 7042 support.

[Mark Lord <liml@rtr.ca>]

Hein-Pieter van Braam wrote:
>> Man, what a quirky BIOS!
>>
>> Okay, so if I connect a drive and don't do anything in the Highpoint BIOS setup,
>> it then corrupts the drive by overwriting the 9th sector on every reboot.
>>
>> But.. if I connect a drive and go into the Highpoint BIOS setup,
>> and "initialize" the drive there, and then set it all as a "JBOD volume",
>> it then leaves the drive content untouched on subsequent reboots.
>>
>> Screwy to the max.
>>
>> So, I might be able to boot from it by cloning the disk *after* setting
>> it to "JBOD" in the BIOS.  That will take a (longish) while to do.
> 
> I've just managed to boot with PXE and 2.6.23.9 and I have come to the
> following:
> 
> * softraid still works
> * sata_mv is a bit slower than the proprietary highpoint drivers (I get
> 300MB/s from my array rather than 400MB/s)
..

No worries.
That performance number will eventually come up as we develop sata_mv more.

NCQ and IRQ-coalescing together oughta do it.  They're "on the list".

> * they array works
> * the content of the array seems to have shifted 'down' a bit, that's
> probably why it won't boot. 
..

Shifted "down" which way, I wonder... ?
Maybe they're using a Host Protected Area, which would explain why I don't
see them modifying the 9th sector after "initializing" (WTF?) my drive as
a JBOD using their BIOS.

What does "hdparm -g /dev/sd*" show with their driver and with our driver?