RTEMS 4.6.1 On-Line Library

Network Configuration

RTEMS Network Supplement

3.3.2: Network Configuration

The network configuration is specified by declaring and initializing the rtems_bsdnet_config structure.

struct rtems_bsdnet_config {
  /*
   * This entry points to the head of the ifconfig chain.
   */
  struct rtems_bsdnet_ifconfig *ifconfig;

  /*
   * This entry should be rtems_bsdnet_do_bootp if BOOTP
   * is being used to configure the network, and NULL
   * if BOOTP is not being used.
   */
  void                    (*bootp)(void);

  /*
   * The remaining items can be initialized to 0, in
   * which case the default value will be used.
   */
  rtems_task_priority  network_task_priority;  /* 100        */
  unsigned long        mbuf_bytecount;         /* 64 kbytes  */
  unsigned long        mbuf_cluster_bytecount; /* 128 kbytes */
  char                *hostname;               /* BOOTP      */
  char                *domainname;             /* BOOTP      */
  char                *gateway;                /* BOOTP      */
  char                *log_host;               /* BOOTP      */
  char                *name_server[3];         /* BOOTP      */
  char                *ntp_server[3];          /* BOOTP      */
};

The structure entries are described in the following table. If your application uses BOOTP/DHCP to obtain network configuration information and if you are happy with the default values described below, you need to provide only the first two entries in this structure.

struct rtems_bsdnet_ifconfig *ifconfig: A pointer to the first configuration structure of the first network device. This structure is described in the following section. You must provide a value for this entry since there is no default value for it.
void (*bootp)(void): This entry should be set to rtems_bsdnet_do_bootp if your application will use BOOTP/DHCP to obtain network configuration information. It should be set to NULL if your application does not use BOOTP/DHCP.
int network_task_priority: The priority at which the network task and network device receive and transmit tasks will run. If a value of 0 is specified the tasks will run at priority 100.
unsigned long mbuf_bytecount: The number of bytes to allocate from the heap for use as mbufs. If a value of 0 is specified, 64 kbytes will be allocated.
unsigned long mbuf_cluster_bytecount: The number of bytes to allocate from the heap for use as mbuf clusters. If a value of 0 is specified, 128 kbytes will be allocated.
char *hostname: The host name of the system. If this, or any of the following, entries are NULL the value may be obtained from a BOOTP/DHCP server.
char *domainname: The name of the Internet domain to which the system belongs.
char *gateway: The Internet host number of the network gateway machine, specified in `dotted decimal' (129.128.4.1) form.
char *log_host: The Internet host number of the machine to which syslog messages will be sent.
char *name_server[3]: The Internet host numbers of up to three machines to be used as Internet Domain Name Servers.
char *ntp_server[3]: The Internet host numbers of up to three machines to be used as Network Time Protocol (NTP) Servers.

In addition, the following fields in the rtems_bsdnet_ifconfig are of interest.

int port: The I/O port number (ex: 0x240) on which the external Ethernet can be accessed.
int irno: The interrupt number of the external Ethernet controller.
int bpar: The address of the shared memory on the external Ethernet controller.

RTEMS Network Supplement