BSP Developer's Guide

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Implementing a MUX-Based Network Interface Driver
typedef struct net_funcs
{
STATUS (*start) (void*); /* driver’s start func */
STATUS (*stop) (void*); /* driver’s stop func */
STATUS (*unload) (void*); /* Driver’s unload func */
int (*ioctl) (void*, int, caddr_t); /* driver’s ioctl func */
STATUS (*send) (void* , M_BLK_ID); /* driver’s send func */
STATUS (*mCastAddrAdd) (void*, char*); /* driver’s mcast add func */
STATUS (*mCastAddrDel) (void*, char*); /* driver’s mcast delete func */
STATUS (*mCastAddrGet) (void*, MULTI_TABLE*);
/* driver’s mcast get fun. */
STATUS (*pollSend) (void*, M_BLK_ID); /* driver’s poll send func */
STATUS (*pollRcv) (void*, M_BLK_ID); /* driver’s poll receive func */
STATUS (*addressForm) (M_BLK_ID, M_BLK_ID, M_BLK_ID);
/* driver’s addr formation func */
STATUS (*packetDataGet) (M_BLK_ID, M_BLK_ID);
/* driver’s pkt data get func */
STATUS (*addrGet) (M_BLK_ID, M_BLK_ID, M_BLK_ID, M_BLK_ID, M_BLK_ID);
/* driver’s pkt addr get func */
} NET_FUNCS;
Within your endLoad( ), initialize these members to point to the appropriate
driver entry points. Thus, start should contain a pointer to your endStart( ), stop
to your endStop( ), unload to your endUnload( ), and so on.
Tracking Link-Level Information: LL_HDR_INFO
The MUX uses LL_HDR_INFO structures to keep track of link-level header
information associated with packets passed from an END to the MUX and from
there up to a protocol. An LL_HDR_INFO structure is passed as an argument to all
stack receive routines (see, Passing a Packet Up to the Protocol: stackRcvRtn( ), p.307).
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typedef struct llHdrInfo
{
int destAddrOffset; /* destination addr offset in mBlk */
int destSize; /* destination address size */
int srcAddrOffset; /* source address offset in mBlk */
int srcSize; /* source address size */
int ctrlAddrOffset; /* control info offset in mBlk */
int ctrlSize; /* control info size */
int pktType; /* type of the packet */
int dataOffset; /* data offset in the mBlk */
} LL_HDR_INFO;
destAddrOffset
Offset into mBlk structure at which the destination address starts.
destSize
Size of destination address.
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