
- •Preface
- •About this book
- •Intended audience
- •Using this book
- •Typographical conventions
- •Further reading
- •Feedback
- •Feedback on ARM TCP/IP
- •Feedback on this book
- •Introduction
- •1.1 A typical embedded networking stack
- •1.2 What is PPP?
- •1.3 ARM TCP/IP requirements
- •1.3.1 Memory requirements
- •1.3.2 CPU requirements
- •1.3.3 Operating system requirements
- •1.4 ARM PPP requirements
- •1.4.1 Line management functions
- •1.4.2 Static memory
- •1.4.3 Dynamic memory
- •1.4.4 Periodic clock tick
- •1.5 Example package directories
- •1.6 Sample programs
- •TCP/IP Porting
- •2.1 Porting procedure
- •2.2 Portable and nonportable files
- •2.2.1 Portable files
- •2.2.2 Nonportable files
- •2.3 Creating the IP port file
- •2.3.1 Standard macros and definitions
- •2.3.2 CPU architecture
- •2.3.4 Debugging aids
- •2.3.5 Timers and multitasking
- •2.3.6 Stack features and options
- •2.4 Coding the glue layer
- •2.4.1 Task control
- •2.5 Specifying IP addresses
- •2.5.1 Porting programmer IP issues
- •2.5.2 End user IP issues
- •2.6 Testing the TCP/IP port
- •PPP Porting
- •3.1 Porting procedure
- •3.2 Porting PPP
- •3.2.1 Source files
- •3.2.2 Compiling PPP
- •3.2.3 Entry points and support calls
- •3.3 Testing PPP
- •3.3.1 Loopback
- •3.3.2 Client connection
- •3.3.3 Server connection
- •3.3.4 Abrupt disconnect
- •3.3.5 Multilink test
- •TCP/IP API Functions
- •4.2.1 cksum()
- •4.2.2 dprintf() and initmsg()
- •4.2.3 dtrap()
- •4.2.4 ENTER_CRIT_SECTION() and EXIT_CRIT_SECTION()
- •4.2.5 LOCK_NET_RESOURCE() and UNLOCK_NET_RESOURCE()
- •4.2.6 npalloc()
- •4.2.7 npfree()
- •4.2.8 panic()
- •4.2.9 prep_ifaces()
- •4.2.10 tcp_sleep()
- •4.2.11 tcp_wakeup()
- •4.3 Network interfaces
- •4.3.1 The NET structure
- •4.3.2 n_close()
- •4.3.3 n_init()
- •4.3.4 n_reg_type()
- •4.3.5 n_stats()
- •4.3.6 pkt_send()
- •4.3.7 raw_send()
- •PPP API Functions
- •5.2.1 _ALLOC() functions
- •5.2.2 ConPrintf()
- •5.2.3 _FREE() functions
- •5.2.4 get_secret()
- •5.2.5 ppp_port_init()
- •5.3 Serial line drivers
- •5.3.1 ln_connect()
- •5.3.2 ln_getc()
- •5.3.3 ln_hangup()
- •5.3.4 ln_putc()
- •5.3.5 ln_speed()
- •5.3.6 ln_state()
- •5.3.7 ln_write()
- •5.4 PPP entry points
- •5.4.1 lcp_lowerdown()
- •5.4.2 lcp_lowerup()
- •5.4.3 ppp_input()
- •5.4.4 ppp_timeisup()
- •5.4.5 prep_ppp()
- •Modem Functions
- •6.1 dialer.c
- •6.1.1 dial()
- •6.1.2 dial_check()
- •6.1.3 dialer_status()
- •6.1.4 modem_cmd()
- •6.1.5 modem_connect()
- •6.1.6 modem_getc()
- •6.1.7 modem_gets()
- •6.1.8 modem_hangup()
- •6.1.9 modem_init()
- •6.1.10 modem_lstate()
- •6.1.11 modem_putc()
- •6.1.12 modem_reset()
- •6.1.13 modem_speed()
- •6.1.14 modem_state()
- •6.1.15 modem_write()
- •6.2 login.c
- •6.2.1 do_script()
- •6.2.2 login()
- •6.2.3 log_input()
- •6.2.4 log_output()
- •6.2.5 logserver()
- •6.3 mdmport.c
- •6.3.1 dial_delay()
- •6.3.2 hangup()
- •6.3.3 modem_clr_dtr() and modem_set_dtr()
- •6.3.4 modem_DCD()
- •6.3.5 modem_portstat()
- •DHCP Client Functions
- •7.1 DHCP client functions
- •7.1.1 dhc_init()
- •7.1.2 dhc_discover()
- •7.1.3 dhc_set_callback()
- •7.1.4 dhc_halt()
- •7.1.5 dhc_second()
- •Low-overhead UDP Functions
- •8.1 UDP functions
- •8.1.1 udp_alloc()
- •8.1.2 udp_close()
- •8.1.3 udp_open()
- •8.1.4 udp_send()
- •8.1.5 udp_socket()
- •Sockets
- •9.1 ARM implementation of sockets
- •9.2 Socket API reference
- •9.2.1 t_accept()
- •9.2.2 t_bind()
- •9.2.3 t_connect()
- •9.2.4 t_errno()
- •9.2.5 t_getpeername()
- •9.2.6 t_getsockname()
- •9.2.7 t_getsockopt()
- •9.2.8 t_listen()
- •9.2.9 t_recv() and t_recvfrom()
- •9.2.10 t_select()
- •9.2.11 t_send() and t_sendto()
- •9.2.12 t_setsockopt()
- •9.2.13 t_shutdown()
- •9.2.14 t_socket()
- •9.2.15 t_socketclose()
- •ARM-specific Functions
- •10.1 ARM directories
- •10.1.1 armthumb
- •10.2 cksum.s
- •10.3 clock.c
- •10.3.1 clock_init()
- •10.3.2 clock_c()
- •10.4 delay.s
- •10.5 dtrap.s
- •10.6 except.s
- •10.7.1 ENTER_CRIT_SECTION() and EXIT_CRIT_SECTION()
- •10.7.2 irqDispatch()
- •10.7.3 irq_Enable() and irq_Disable()
- •10.7.4 irqInit()
- •10.8 lswap.s
- •10.10 olicom.c
- •10.11 pcmcia.c
- •10.12 stack.s
- •10.13 uart.c description
- •10.14 uart.c ring buffer management functions
- •10.14.1 ring_add()
- •10.14.2 ring_avail()
- •10.14.3 ring_new()
- •10.14.4 ring_remove()
- •10.14.5 ring_space()
- •10.15 uart.c interface functions
- •10.15.1 uart_getc()
- •10.15.2 uart_DCD()
- •10.15.3 uart_delay()
- •10.15.4 uart_do_irq()
- •10.15.5 uart_init()
- •10.15.6 uart_irq()
- •10.15.7 uart_putc()
- •10.15.8 uart_ready()
- •10.15.9 uart_reset()
- •10.15.10 uart_setup()
- •10.15.11 uart_stats()
- •10.16 uart.c debug TTY interface functions
- •10.16.1 dputchar()
- •10.16.2 getch()
- •10.16.3 kbhit()
- •Miscellaneous Library Functions
- •11.1 app_ping.c
- •11.2 in_utils.c
- •11.2.1 con_page()
- •11.2.2 hexdump()
- •11.2.3 nextarg()
- •11.2.4 ns_printf()
- •11.2.5 panic()
- •11.2.6 print_eth()
- •11.2.7 print_ipad()
- •11.2.8 print_uptime()
- •11.2.11 sysuptime()
- •11.2.12 uslash()
- •11.3 memman.c
- •11.4 menus.c, menulib.c, and nrmenus.c
- •11.5 nextcarg.c
- •11.5.1 nextcarg()
- •11.6 nvfsio.c
- •11.6.1 Overview
- •11.6.2 nv_fclose()
- •11.6.3 nv_fgets()
- •11.6.4 nv_fopen()
- •11.6.5 nv_fprintf()
- •11.6.6 nv_fwrite()
- •11.6.7 nv_initialize()
- •11.6.8 nv_writeflash()
- •11.7 nvparms.c
- •11.8 parseip.c
- •11.8.1 parseip()
- •11.9 reshost.c
- •11.9.1 in_reshost()
- •11.10 strilib.c
- •11.11 strlib.c
- •11.12 tcp_echo.c
- •11.13 ttyio.c
- •11.14 udp_echo.c
- •11.15 userpass.c
- •11.15.1 add_user()
- •11.15.2 check_permit()
- •Example Applications
- •12.1 Overview of the examples
- •12.1.1 Requirements
- •12.1.2 Building projects
- •12.1.3 Running the examples
- •12.2 Example descriptions
- •12.2.1 chargen
- •12.2.2 loopback
- •12.2.3 maildemo
- •12.2.4 menus
- •Error Codes
- •A.1 ENP_ error codes
- •A.2 Socket error codes

ARM-specific Functions
10.2cksum.s
The file cksum.s contains optimized ARM and Thumb versions of the cksum() function. IP, UDP, TCP, and PPP use this function to calculate the checksum of a block of data. The algorithm implemented is described by RFC 1072. A C version of this function is also provided, in the \inet directory, but this should only be used if you suspect that there is some problem with these optimized versions.
It is possible to optimize the ARM implementation of this function by setting the NREG variable within this file to a value between one and eight. NREG controls the number of registers used to perform the checksumming operation. The default value of five has been selected through a benchmarking process. The ARMulator is used to emulate an ARM7TDMI core without caching, while performing TCP and UDP transfers of varying block sizes using the Loopback example program. You may want to run performance tests on your system to determine the best value to use, especially if the processor you are using has a data cache.
ARM DUI 0079B |
Copyright © 1998 and 1999 ARM Limited. All rights reserved. |
10-5 |