RE: IDE/Promise 20276 FastTrack RAID Doesn't work in 2.4.21, patchattached to fix

Bartlomiej Zolnierkiewicz
2003-07-10T22:42:34Z

On Thu, 10 Jul 2003, Chad Kitching wrote:

> I don't know. That seemed to have changed the option from merely
> mystifying to down right confusing. By that wording, does that feature
> override it into being a plain IDE controller, or an IDE RAID controller?
> The new name seems to imply the former, while the mentions
> of ataraid suggest the latter.

Hmmm... you are right. Comment is still misleading in respect to RAID.

ataraid driver is a _software_ RAID, just like Promise's binary driver.

FastTracks have software RAID. There are few true hardware FastTrak
RAID controllers with I2O interface but we probe for them properly in
pdc202xx_new.c driver and don't use IDE driver for them.

> Despite the grammatical errors, pdc202xx.c's comments perhaps describe it
> better.
> * Linux kernel will misunderstand FastTrak ATA-RAID series as Ultra
> * IDE Controller, UNLESS you enable "CONFIG_PDC202XX_FORCE"
> * That's you can use FastTrak ATA-RAID controllers as IDE controllers.

It is quite opposite.

> If this is true, may I suggest something more along the lines of:
>
> Ignore FastTrak BIOS and configure controller for RAID
> CONFIG_PDC202XX_FORCE
> Forces the driver to use the ATA-RAID capabilities, overriding the
> BIOS configuration of the controller. Do not enable if you are
> using Promise's binary module. This option is compatible with the
> ataraid driver.

What about this:

Ignore FastTrak BIOS
CONFIG_PDC202XX_FORCE
Forces the driver to use FastTrak controller even if it was disabled
by BIOS for Promise software RAID driver.

Say Y if you do not use Promise's software RAID or
if you want to use ataraid driver.

Say N if you want to use Promise's binary module.

> If the Linux driver has the same limitation in regards to using CD-ROM
> drives on the controller while it's in RAID mode as the Windows drivers
> do, it may be useful to mention the fact that the option is incompatible
> with CD-ROM drives attached to the controller.

It has. According to Andre it is doable but big pain,
also Promise gives docs under NDA which makes it even harder.

Please search lkml archive if you want know technical details.

> Of course, maybe it means the complete opposite, and I'm reading everything
> wrong, in which case, there are some comments you may want to fix, too.

Comments in Promise driver need fixing.

Thanks,
--
Bartlomiej

> -----Original Message-----
> From: Samuel Flory
> Sent: July 10, 2003 4:11 PM
> Subject: Re: IDE/Promise 20276 FastTrack RAID Doesn't work in 2.4.21,
> patchattached to fix
>
>
> Bartlomiej Zolnierkiewicz wrote:
>
> >Hi,
> >
> >Do you have "Special FastTrak Feature" enabled?
>
> Can we change the option to something that makes sense. I get the
> feeling no one understands what it does at 1st glance. This is the 2nd
> time I've seen a patch like this.