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The ge driver is a Style 2 data link service provider.
All M_PROTO and M_PCPROTO type messages are interpreted as DLPI primitives. Valid DLPI
primitives are defined in <sys/dlpi.h>. Refer to dlpi(7P) for more
information.
You must send an explicit DL_ATTACH_REQ message to associate the opened stream with a particular device
(ppa). The ppa ID is interpreted as
an unsigned long data type and indicates the corresponding device
instance (unit) number. An error (DL_ERROR_ACK) is returned
by the driver if the ppa field value does not correspond
to a valid device instance number for the system. The device is initialized
on first attach and de-initialized (stopped) upon last detach.
The values returned by the driver in the DL_INFO_ACK primitive in response to the DL_INFO_REQ are:
- Maximum SDU is 1500 (ETHERMTU - defined in <sys/ethernet.h> ).
- Minimum SDU is 0.
-
dlsap address length is 8.
-
MAC type is DL_ETHER.
-
sap length value is -2,
meaning the physical address component is followed immediately by a 2 byte sap component within the DLSAP
address.
- Service mode is DL_CLDLS.
- Quality of service (QOS) is not supported; accordingly, QOS fields are 0.
- Provider style is DL_STYLE2.
- Version is DL_VERSION_2.
- Broadcast address value is Ethernet/IEEE broadcast address
(0xFFFFFF).
Once in the DL_ATTACHED state,
you must send a DL_BIND_REQ to associate
a particular Service Access Pointer (SAP)
with the stream. The ge driver interprets the sap field within the DL_BIND_REQ as an Ethernet type; accordingly, valid values
for the sap field are in the [0-0xFFFF] range. Only one Ethernet type can be bound to the stream
at any time.
If you select a sap with a value of 0,
the receiver will be in 802.3 mode. All frames received
from the media with a type field in the range [0-1500] are assumed to be 802.3 frames and
are routed up all open streams bound to sap value 0. If more than one stream is in 802.3 mode,
the frame will be duplicated and routed up multiple streams as DL_UNITDATA_IND messages.
In transmission, the driver checks the sap field
of the DL_BIND_REQ to determine
if the sap value is 0 and the destination
type field is in the range [0-1500].
If either is true, the driver computes the length of the message, not including
initial M_PROTO mblk (message block),
of all subsequent DL_UNITDATA_REQ
messages and transmits 802.3 frames of that value in
the MAC frame header length field.
The ge driver DLSAP address format consists of the 6 byte physical (Ethernet) address
component followed immediately by the 2 byte sap (type)
component producing an 8 byte DLSAP
address. Applications should not hard code to this
particular implementation-specific DLSAP
address format, but use information returned in the DL_INFO_ACK primitive to compose and decompose DLSAP addresses. The sap length, full DLSAP length and sap physical
ordering are included within the DL_INFO_ACK. The physical address length can be computed by subtracting the sap length from the full DLSAP
address length or by issuing the DL_PHYS_ADDR_REQ to obtain the current physical address associated with the stream.
Once in the DL_BOUND state,
you may transmit frames on the Ethernet by sending DL_UNITDATA_REQ messages to the ge driver. The ge driver will route received Ethernet frames up all open and bound
streams having a sap which matches the Ethernet type as DL_UNITDATA_IND messages. Received Ethernet
frames are duplicated and routed up multiple open streams if necessary. The DLSAP address contained within the DL_UNITDATA_REQ and DL_UNITDATA_IND messages consists of both the sap
(type) and physical (Ethernet) components.
In addition to the mandatory connectionless DLPI message set, the driver additionally supports ge primitives.
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