Tim, Thanks for the reply. The 2900 that we have in our lab has no BIOS option for AHCI support that I can see. The Dell support staff could not tell me much about this either and suggested that I post here. In fact, even though they didn't seem to know much about AHCI, they had heard of it and believed it is disabled on many PE platforms.
Is AHCI the common API for communicating to the SATA H/W by most O/S's? Is this what Linux uses or is there another API that provides cross platform support? The AHCI emulation mode sounds nice since it would allow our existing IDE driver to support SATA here with little work. Having said that, I am not opposed to writing a new SATA driver which does not use emulation mode providing that it will offer cross platform support. Would this also be AHCI but without emulation mode? I keep thinking there may be some other API (other than AHCI) to consider since Dell may be disabling the AHCI on many PE platforms. Our bootstrap logic which examines PCI configuration space seems to find an AHCI footprint but the IRQ is zero which doesn't seem right. Our RMS operating system was created in 1980 and we still have a lot of customers who use applications written for it on Dell PowerEdge platforms. Larry -----Original Message----- From: Tim Small [mailto:[email protected]] Sent: Saturday, December 05, 2009 6:47 AM To: Larry White Cc: [email protected] Subject: Re: PowerEdge 2900 Onboard SATA API? Difficult to say really - AHCI is probably a cleaner interface from what I know, and is likely to be more future-proof. Dunno about the 2900, but at least some PEs don't give a BIOS option to put the Intel ICH SATA controllers into AHCI mode, but you can always just do that yourself by reprogramming the necessary register (see the Intel datasheet - it says that the OS should leave this to the firmware, but I'm think it's probably safe to do so between bootstrap and controller init time). As soon as I have a client who will fund it, I'm planning to implement this myself as a Linux PCI fixup... Might be worth looking at doing this yourselves as a simple proof of concept / sanity-check. Out of interest why do you maintain your own OS? Hard realtime? Cheers, Tim. _______________________________________________ Linux-PowerEdge mailing list [email protected] https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
