SMSC LAN9312 - Manual (Page 68)

High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface
Datasheet
Revision 1.4 (08-19-08) 68 SMSC LAN9312
DATASHEET
The transmit queue priority is based on the packet type and device configuration as shown in
Figure 6.5 . Refer to Section 14.5.3.16, "Switch Engine Global Ingress Configuration Register
(SWE_GLOBAL_INGRSS_CFG)," on page 383 for definitions of the configuration bits.
Figure 6.5 Switch Engine Transmit Queue Calculation
Queue =
ALR Priority
DA Highest
Priority
ALR Static Bit
Y
Y
Resolved Priority =
Priority Regen[VLAN
Priority]
N
Packet is IPv 4/v6
& Use IP
Resolved Priority =
IP Precedence
Y
Use Precedence
Y N
Resolved Priority =
DIFFSERV[TC]
N
N
Y
VLAN Enable &
Packet is
Tagged
Y
N
N
Resolved Priority =
Default Priority[Source
Port]
wait for ALR result
Queue =
Traffic Class[Resolved Priority]
Packet is IPv 4
Resolved Priority =
DIFFSERV[TOS]
Y
N
Get Queue Done
VL Higher
Priority
VLAN Enable &
Packet is
Tagged
N
Y
Get Queue
Packet from Host
N
Y