SATA hotplug notifications for BMC inventory updates

[Johnathan Mantey]

On 9/5/22 04:11, Paul Fertser wrote:
> Hi,
>
> An OCP Tioga Pass platform features up to 4 drive bays for SATA
> storage accessible from the front and fully hot-pluggable. The
> backplane is usually connected directly to Intel C620 PCH (aka
> Lewisburg).
>
> It would be nice to have information about the currently attached
> devices (model and serial number) available in BMC inventory but what
> are the ways to get this information?

Intel systems only get drive mdl/sn from NVMe devices that provide that 
information via MCTP over SMBus. SAS/SATA drives, to my current 
knowledge, don't supply this info in that mode.

The insertion/removal events are also managed from the BMC via I2C to a 
FPGA solution residing on the Hot Swap Backplane. The FPGA provides 
registers that allow the BMC to query the PRSTn/IFDETn pins.

>
> Is it possible there's some additional module in the all-mighty ME
> that can supply BMC with the current state of PCH SATA controller? Or
> is there some other sensible mechanism other than talking to UEFI on
> startup (which would mean BMC is showing stale and thus misleading
> data till the next reboot)?
>
> Even though the question is quite specific we'd appreciate any related
> insights on the topic; there must be some side-channels to RAID
> controllers and such for BMC to be obtaining essential information but
> so far I wasn't able to find any documentation about this.
RAID solutions are outside of scope for the Intel BMC.

-- 
Johnathan Mantey
Senior Software Engineer
*azad te**chnology partners*
Contributing to Technology Innovation since 1992
Phone: (503) 712-6764
Email: johnathanx.mantey at intel.com
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