Re: SSD SATA 3.3 and Broadcom / LSI SAS1068E PCI-Express Fusion-MPT SAS

From: Bjorn Helgaas
Date: Tue Aug 15 2023 - 13:50:23 EST


On Tue, Aug 15, 2023 at 01:35:35AM +0200, deloptes wrote:
> Bjorn Helgaas wrote:
>
> > I don't know why that would be.  Are there any hints in the dmesg log?
> > Can you collect the complete dmesg log with the old drives and again
> > with the new SSDs so we can compare them?  I assume you have good
> > cables?  I assume the same cables worked at 3.0 Gb/s with the old
> > drives.
> >
> > I would *expect* that SATA r3.3 would be completely backwards
> > compatible, so since mptsas worked just fine at 3.0 Gb/s with the old
> > SATA r3.0 drives, it should also work just fine at 3.0 Gb/s with the
> > new SATA r3.3 drives.  But I have no actual knowledge about that.
>
> Thank you for your answer. I am also confused and couldn't think of any
> meaningful reason. This is why I allowed myself to bother you.
>
> I did not change anything - wiring or such. The server has 12 disk bays on
> the front. Old disks were pulled out and new disks were inserted into the
> bays.
>
> You (probably much knowable in this matters than me) also assume negotiation
> should result in 3.0Gb/s. And if I understand correctly it should be not a
> driver issue.
>
> The only difference I could find out for now is that Rev3.3 introduced PWDIS
> on Pin 3. To check if the cables provide wiring on P3 I should disassemble
> the server, but I can do this in September :/ and it is a lot of effort.
>
> I am attaching a portion of the log and dmesg with the relevant information.
> I see that ASPM is disabled by default (could it be related to P3?).

ASPM is a PCIe feature that applies to the PCIe Links between 00:02.0
and 01:00.0 (the first 1068E) and 00:15.0 and 08:00.0 (the second
1068E).

PWDIS is a feature on the SATA cables between the SAS1068E adapters
and the SSDs.

PWDIS/P3 should not be related to ASPM. I assume you're referring to
the "disabling ASPM on pre-1.1 PCIe device" message. That should
happen with both the old r3.0 HDDs and the new r3.3 SSDs.

I wish I had some good ideas for you, but I don't know anything about
the SATA side. I googled for "1068 ssd sata 1.5 gb/s" and found a few
hints about system firmware, LSI firmware, etc, but nothing concrete.

I think some controllers have a BIOS setup user interface; have you
poked around in there?

Bjorn