Re: Devices behind PEX 8664 PCIe Switch not detected since 11.0-RELEASE

From: Christopher Forgeron <csforgeron_at_gmail.com>
Date: Wed, 09 Jun 2021 15:23:53 UTC
Hello,

 I'm not sure if I should try posting on a different mail list? The problem
is still here, it's beyond my ability to fix, and I'm willing to actively
help out anyone who can point me in the right direction - Anyone with any
ideas?

On Tue, Jun 1, 2021 at 10:44 PM Christopher Forgeron <csforgeron@gmail.com>
wrote:

> Hello,
>
>  I have not been able to upgrade past FreeBSD 10.3 as since versions 11.0 -> 13.0 devices behind my fileserver's PCIe Switch are not detected. The switch itself is detected, which is a PEX 8664 PCIe Switch, link below.
>
>  I'm using a Dell M610x blade server, which has a PEX/Broadcom 8664 Switch in it to provide 2 PCIe slots, which I use to run SAS controllers to a drive array.
>
>  This arrangement has worked perfectly since the early days of 7/8.0, and I've pretty much ran each version of FreeBSD since then, until 11.0 came out.
>
>  This is when I could no longer see/detect devices plugged into the PCIe slots. Things were busy, FreeBSD 10.2 worked well, so it was just left this way for years.
>
>  Now I do need to upgrade software-wise to 13.0, so I've invested some time tracking down what is happening, with the hopes that a knowledgeable person can fix this up.
>
>  - I have confirmed with 10.3-RELEASE and a 11.0-RELEASE mini-iso boot that the problem starts in 11.0, and I can confirm it's still an issue in 12.0 and 13.0. I also boot into a 10.2-RELEASE because I happen to have that handy.  Everything works/detects fine in 10.3 or lower.
>
>  - These are GENERIC kernels, fresh from the iso/img I boot from, nothing custom.
>
>  - I currently have a 10.2 (or 10.3) boot and a 13.0 boot ready to swap back and forth to try and isolate / probe info. I'll attach a few lspci dumps after this message.
>
>  - The card in question is a LSI 2008 Chipset, mps0 - But it's nothing do do with that card/brand/config. I have also installed an Intel X540 Network card in the PCIe slots and find the same issue - There's nothing behind the PEC 8664 in FreeBSD 13.0, and no problems in 10.2. I have also confirmed that 13.0 boots up and detects the mps0 without issue when I use a different system without the PEX 8664
>
>  - At some point in my research I came across a similar issue where the developer mentioned that for some reason they were not scanning behind the switch. It was a different chipset and issue, and  I don't have that thread handy at the moment, I will post if I come across it again.
>
> Ref:https://www.broadcom.com/products/pcie-switches-bridges/pcie-switches/pex8664
>
> I'm rusty, but fairly knowledgeable and useful if you need me to compile something, install patches, etc. I could give SSH access, but sending me a patch to test may be quicker.
>
> lspci dumps are in my bug report here:
>
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=256264
>
> Thanks.
>
>