Re: [PATCH 2/5] I2O: SPARC fixes

From: Markus Lidel
Date: Sun Nov 20 2005 - 16:38:40 EST


Alan Cox wrote:
On Gwe, 2005-11-18 at 17:22 -0800, David S. Miller wrote:
Ho hum, I guess keep it a config option for now until we find a
way to auto-detect this reliably.
The notify functionality is mandatory. You are seeing the same cards
fail on sparc but work on x86. This sounds to me a lot more like an
unfound endian bug that needs fixing than a real lack of support
That's very possible, but it also could be that the cards
that fail only on Sparc have Sun forth firmware on them,
which would thus only load firmware on Sparc boxes.
The firmware on the DPT I2O card processor is kept in flash on the
processor. The BIOS setup code might be different but nothing at the
business end of things

That's right there are two different firmwares. One for "Intel"-cards and one for SUN-cards. The LCT-Notify function works as follow.

The LCT on the I2O controller has a change indicator which is incremented by the I2O controller each time something changes (e. g. a disk is removed or added or so). The i2o_exec_lct_notify() function only send a number to the I2O controller. If this number is <= then the current change indicator of the LCT, then the controller send out the new LCT to the OS. On startup the change indicator is normally 1. So if there is some BE<->LE issue, then the function wouldn't send in 0x00000002 but 0x02000000. What should happen then is that you won't be notified for a long time. But that didn't happened, and the controller immediately send out the LCT, although if you send in 0xffffffff. And as i'm told, this is wanted for some reason for the "SUN"-firmware.

It should probably be "fixed" if you upload a "Intel"-firmware onto the I2O controller, but because i don't own a SPARC machine with a PCI slot myself, i don't want to try it out on someones else machine and probably break it :-)

If someone has a SPARC machine with an I2O controller, and he want to try it out, please let me know...

Markus Lidel (Senior IT Consultant)

Shadow Connect GmbH
Carl-Reisch-Weg 12
D-86381 Krumbach

Phone: +49 82 82/99 51-0
Fax: +49 82 82/99 51-11

E-Mail: Markus.Lidel@xxxxxxxxxxxxxxxxx
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