diff options
| author | Jacob McDonnell <jacob@jacobmcdonnell.com> | 2026-04-25 16:08:12 -0400 |
|---|---|---|
| committer | Jacob McDonnell <jacob@jacobmcdonnell.com> | 2026-04-25 16:08:12 -0400 |
| commit | b9cde963555b6519c5dbd34a39dee3418f593437 (patch) | |
| tree | 453accad3c3286e3416d4160de4a87223aff684c /static/freebsd/man4/imcsmb.4 | |
| parent | 5cb84ec742fd33f78c8022863fadaa8d0d93e176 (diff) | |
feat: Added FreeBSD man pages
Diffstat (limited to 'static/freebsd/man4/imcsmb.4')
| -rw-r--r-- | static/freebsd/man4/imcsmb.4 | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/static/freebsd/man4/imcsmb.4 b/static/freebsd/man4/imcsmb.4 new file mode 100644 index 00000000..4a8f9e50 --- /dev/null +++ b/static/freebsd/man4/imcsmb.4 @@ -0,0 +1,130 @@ +.\" +.\" SPDX-License-Identifier: BSD-2-Clause +.\" +.\" Copyright (c) 2018 Panasas +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, +.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.Dd March 2, 2018 +.Dt IMCSMB 4 +.Os +.Sh NAME +.Nm imcsmb +.Nd Intel integrated Memory Controller (iMC) SMBus controller driver +.Sh SYNOPSIS +.Cd device pci +.Cd device smbus +.Cd device imcsmb +.Pp +Alternatively, to load the driver as a module at boot time, place the following +line in +.Xr loader.conf 5 : +.Bd -literal -offset indent +imcsmb_load="YES" +.Ed +.Sh DESCRIPTION +The +.Nm +driver provides +.Xr smbus 4 +support for the SMBus controller functionality in the integrated Memory +Controllers (iMCs) embedded in Intel Sandybridge-Xeon, Ivybridge-Xeon, +Haswell-Xeon, and Broadwell-Xeon CPUs. +Each CPU implements one or more iMCs, depending on the number of cores; +each iMC implements two SMBus controllers (iMC-SMBs). +The iMC-SMBs are used by the iMCs to read configuration information from the +DIMMs during POST. +They may also be used, by motherboard firmware or a BMC, to monitor the +temperature of the DIMMs. +.Pp +The iMC-SMBs are +.Sy not +general-purpose SMBus controllers. +By their nature, they are only ever attached to DIMMs, so they implement only +the SMBus operations need for communicating with DIMMs. +Specifically: +.Pp +.Bl -dash -offset indent -compact +.It +READB +.It +READW +.It +WRITEB +.It +WRITEW +.El +.Pp +A more detailed discussion of the hardware and driver architecture can be found +at the top of +.Pa sys/dev/imcsmb/imcsmb_pci.c . +.Sh WARNINGS +As mentioned above, firmware might use the iMC-SMBs to read DIMM temperatures. +The public iMC documentation does not describe any sort of coordination +mechanism to prevent requests from different sources -- such as the motherboard +firmware, a BMC, or the operating system -- from interfering with each other. +.Pp +.Bf Sy +Therefore, it is highly recommended that developers contact the motherboard +vendor for any board-specific instructions on how to disable and re-enable DIMM +temperature monitoring. +.Ef +.Pp +DIMM temperature monitoring should be disabled before returning from +.Fn imcsmb_pci_request_bus , +and re-enabled before returning from +.Fn imcsmb_pci_release_bus . +The driver includes comments to that effect at the appropriate locations. +The driver has been tested and shown to work, with only that type of +modification, on certain motherboards from Intel. +.Po +Unfortunately, those modifications were based on material covered under a +non-disclosure agreement, and therefore are not included in this driver. +.Pc +The driver has also been tested and shown to work as-is on various motherboards +from SuperMicro. +.Pp +The +.Xr smb 4 +driver will connect to the +.Xr smbus 4 +instances created by +.Nm . +However, since the IMC-SMBs are not general-purpose SMBus controllers, using +.Xr smbmsg 8 +with those +.Xr smb 4 +devices is not supported. +.Sh SEE ALSO +.Xr jedec_dimm 4 , +.Xr smbus 4 +.Sh HISTORY +The +.Nm +driver first appeared in +.Fx 12.0 . +.Sh AUTHORS +The +.Nm +driver was originally written for Panasas by +.An Joe Kloss . +It was substantially refactored, and this manual page was written, by +.An Ravi Pokala Aq Mt rpokala@freebsd.org |
