Specifications

BMC Messaging Interfaces QSSC-S4R Technical Product Specification
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Bu t,  (per channel session limi t ) (bulle t 4) > ( t o t al session slo t s) (bulle t 3) ; t his is done so t ha t t he available slo t s can
be used op t imally . Even t hen , t he user migh t no t be able t o open t he Maximum # sessions per channel on a par t icular
channel . The Maximum per channel session limi t is used only t o main t ain f airness in session usage across t he
Channels . The Ge t Session I n f o() command will re t urn t he hard- coded (see bulle t 3) value o f t he t o t al MAX session
slo t s available .
The Se t UserAccess() Command can be used t o limi t t he number o f concurren t sessions open per user . This user
con f igured value t oge t her wi t h t he in t ernal hard- coded per channel session limi t s (bulle t 4) migh t some t imes no t
allow t he usage o f all session slo t s . Finally (bulle t 5) f ur t her resource cons t rain t s migh t no t allow t he f ull u t iliza t ion o f
t he session slo t s , in t hose cases t he FW migh t dynamically reduce t he number o f slo t s available .
On QSSC-S4R platform, maximum no of IPMI over LAN sessions are configured as 16 (par LAN channel) and to
ensure web server availability, 4 session slots are reserved for Embedded Web Server. Total no of possible sessions
at any point of time are 36.
25.4 Media Bridging
The BMC suppor t s bridging be t ween t he LAN and I PMB in t er f aces . This allows t he s t a t e o f o t her in t elligen t con t rollers
in t he chassis t o be queried by remo t e console so ft ware . Reques t s may be direc t ed t o con t rollers on t he I PMB , bu t
reques t s origina t ing on t he I PMB canno t be direc t ed t o t he LAN in t er f ace unless t he reques t is origina t ed by t he ME
on t he secondary I PMB .
Available bridging combina t ions :
x
KCS t o I PMB (Primary)
x
KCS t o I PMB (Secondary)
x
LAN t o I PMB (Primary)
x
LAN t o I PMB (Secondary)
x
I PMB (Secondary) t o LAN
25.5 Request / Response Protocol
The pro t ocols are reques t / response pro t ocols . A reques t message is issued t o an in t elligen t device . The in t elligen t
device responds wi t h a response message . For example , wi t h respec t t o t he I PMB in t er f ace , bo t h reques t messages
and response messages are t ransmi tt ed on t he bus using I
2
C mas t er wri t e t rans f ers . An in t elligen t device ac t ing as
an I
2
C mas t er issues a reques t message . This is received by an in t elligen t device as an I
2
C slave . The corresponding
response message is issued f rom t he responding in t elligen t device as an I
2
C mas t er , and is received by t he reques t
origina t or as an I
2
C slave .
25.6 Host to BMC Communication Interface
25.6.1 LPC / KCS Interface
The BMC f irmware suppor t s t wo 8042 keyboard con t roller s t yle (KCS) in t er f ace por t s as described in t he I n t elligen t
Pla tf orm Managemen t I n t er f ace Speci f ica t ion Second Genera t ion v2 . 0 . These in t er f aces are mapped in t o t he hos t I/ O
space and accessed via t he chipse t LPC bus . These in t er f aces are assigned wi t h t he f ollowing uses and addresses :
Table 195. Keyboard Controller Style Interfaces
Name
Use Address
SMS Interface
SMS, BIOS POST, and utility
access
0CA2h –
0CA3h
SMM Interface
SMI handling for error logging 0CA4h –
0CA5h
The
BMC gives higher priori t y t o t rans f ers occurring t hrough t he server managemen t mode (SMM) in t er f ace . This
provides minimum la t ency during SM I accesses . The BMC ac t s as a bridge be t ween t he server managemen t
so ft ware (SMS) and t he I PMB in t er f aces . I n t er f ace regis t ers provide a mechanism f or communica t ions be t ween t he
BMC and t he hos t sys t em . Mos t pla tf orms implemen t t he in t er f aces as hos t I/ O space mapped regis t ers . The
in t er f aces consis t o f t hree se t s o f t wo 1-by t e- wide regis t ers .