SAS/SATA controllers & KEXTs

[David Lethe]

I got myself a new macbook pro, so needless to say, I am dissatisfied with the limitations in the O/S and architecture to let me pretty much hook up anything I want and be able to talk to it within OS/X. My biggest problem is that Apple refuses to provide a generic pass-though mechanism for disk drives, and they don't have an external docking station like Dell/IBM. There is no expresscard fibre channel controller, or even a SAS controller (the SATA ones wont support SAS disks).

 

I've solved the hardware problem with a Magma expresscard -> PCI-e bridge product (very overpriced), but need to take it to the next level. I want to get RAID management configuration, tuning, and do some things that Apple will never provide, but that I need.

 

The key to this is getting a kext written that allows pass-through SCSI commands. I found some things that are promising, but this is one area of expertise I am lacking in. Has anybody managed to write one? With all of the hobbyist hardware that has been done here, I'm crossing fingers somebody has something that can be adapted.

 

For what it is worth, I have access to resources that others do not have, like non-disclosures with LSI, HP, and am intimately familiar with the MPT libraries (as they pertain to non-Apple hardware), so I think I could eventually even provide a cheap "hobbyist" SAS / RAID and/or fibre channel controller for people who have the need for speed and portability. [if for no better reason, to stick it to Magma who wants $795 for something that is little more than an enclosure, a $50 bridge chip, some simple firmware ... but I would need a kext to make it all happen.

 

If anybody has any questions about disk technology, controllers, RAID, etc, feel free to contact me. I've been a storage architect for 20 years now, so have pretty much done it all. [but I will not break any non-disclosures .. bend them a bit if I can, but won't reveal trade secrets].

[treminaor]

It sounds like you should have just sprung for the Mac Pro, not the laptop.

And, as you have made clear, Apple does not generally provide for customization or upgradability, or, at least nothing past a new hard drive or more RAM.

This forum is geared towards writing kext's for x86 based Mac's, and probably won't be able to server your needs.

 

But who knows, maybe someone here will make today your lucky day...

[SpesAdiratus]

Hi David,

 

I too would be very interested in being able to do something like this. I am new to the field, I/OKit and Mac programming in general and having a little trouble finding out how I can send ATA/SCSI commands directly to a hard drive connected to the HBA.

 

I currently have a Mac Pro and when connecting a hard drive to the HBA the I/OKit registers a series of IOAHCIFamily drivers to handle it. I have been informed that this family of drivers is not open and generally sending ATA commands through the HBA is unsupported. I found that the HBA in my Mac Pro is built into the Intel ICH10 southbridge of my chipset so I figured I could either:

 

1.) Switch the SATA controller to Legacy mode and subclass the drivers in the IOATAFamily which are open source. (having trouble finding out how to do this... supposedly ICH10 supports this but I'm not sure how to switch it)

2.) Write my own AHCI drivers from scratch (knowledge of this is close to nothing aside from a little knowledge (and I mean tiny amount) of kext development, I would have to start from the beginning.... definitely not the favored option).

 

It's quite frustrating that Apple deems that a passthrough should not be provided given that every other platform has one. If we want to be able to tinker with (or even break) the systems we paid for, shouldn't we have the right to??

 

If anyone has any information or would know of any documentation that would help me out it would be extremely appreciated.

[vladthebad]

Might consider seeing how hard it would be to port MegaRAID drivers... then just using an LSI megaraid card. If you get the MegaRAID stuff working, that'd be FREAKING AWESOME.

 

If your going that route, any chance you could make it also run the LSI 2008? (6Gb/s SAS controller)

other cards I'd LOOOVE to get working are a Megaraid 320-2E PCIe SCSI card.

 

If it helps any, OSX supports the LSI1068e in HBA mode out of the box, along with the LSI 53c1020/1030 SCSI chip. (Just not in megaraid configurations)

 

 

For testing, I've got a 1068e, a 2008 (so both 3Gb/s and 6Gb/s SAS controllers) a backplane with LSI 28 port 3Gb/s SAS expander, and the Megaraid 320-2E card.

 

Can likely get other gear to test with as well if needed.

 

Hi David,

 

I too would be very interested in being able to do something like this. I am new to the field, I/OKit and Mac programming in general and having a little trouble finding out how I can send ATA/SCSI commands directly to a hard drive connected to the HBA.

 

I currently have a Mac Pro and when connecting a hard drive to the HBA the I/OKit registers a series of IOAHCIFamily drivers to handle it. I have been informed that this family of drivers is not open and generally sending ATA commands through the HBA is unsupported. I found that the HBA in my Mac Pro is built into the Intel ICH10 southbridge of my chipset so I figured I could either:

 

1.) Switch the SATA controller to Legacy mode and subclass the drivers in the IOATAFamily which are open source. (having trouble finding out how to do this... supposedly ICH10 supports this but I'm not sure how to switch it)

2.) Write my own AHCI drivers from scratch (knowledge of this is close to nothing aside from a little knowledge (and I mean tiny amount) of kext development, I would have to start from the beginning.... definitely not the favored option).

 

It's quite frustrating that Apple deems that a passthrough should not be provided given that every other platform has one. If we want to be able to tinker with (or even break) the systems we paid for, shouldn't we have the right to??

 

If anyone has any information or would know of any documentation that would help me out it would be extremely appreciated.