Board-Specific Configurations ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Table of Contents ^^^^^^^^^^^^^^^^^ o Board-Specific Configurations o Summary of Files o Supported Architectures o Configuring NuttX Board-Specific Configurations ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The NuttX configuration consists of: o Processor architecture specific files. These are the files contained in the arch// directory. o Chip/SoC specific files. Each processor processor architecture is embedded in chip or System-on-a-Chip (SoC) architecture. The full chip architecture includes the processor architecture plus chip-specific interrupt logic, general purpose I/O (GIO) logic, and specialized, internal peripherals (such as UARTs, USB, etc.). These chip-specific files are contained within chip-specific sub-directories in the arch// directory and are selected via the CONFIG_ARCH_name selection o Board specific files. In order to be usable, the chip must be contained in a board environment. The board configuration defines additional properties of the board including such things as peripheral LEDs, external peripherals (such as network, USB, etc.). These board-specific configuration files can be found in the configs// sub-directories and are discussed in this README. The configs/ subdirectory contains configuration data for each board. These board-specific configurations plus the architecture-specific configurations in the arch/ subdirectory completely define a customized port of NuttX. Directory Structure ^^^^^^^^^^^^^^^^^^^ The configs directory contains board specific configurationlogic. Each board must provide a subdirectory under configs/ with the following characteristics: |-- include/ | `-- (board-specific header files) |-- src/ | |-- Makefile | `-- (board-specific source files) |-- Make.defs |-- defconfig `-- setenv.sh Summary of Files ^^^^^^^^^^^^^^^^ include/ -- This directory contains board specific header files. This directory will be linked as include/arch/board at configuration time and can be included via '#include '. These header file can only be included by files in arch/include/ and arch//src src/ -- This directory contains board specific drivers. This directory will be linked as arch//src/board at configuration time and will be integrated into the build system. src/Makefile -- This makefile will be invoked to build the board specific drivers. It must support the following targets: libext$(LIBEXT), clean, and distclean. Make.defs -- This makefile fragment provides architecture and tool-specific build options. It will be included by all other makefiles in the build (once it is installed). This make fragment should define: Tools: CC, LD, AR, NM, OBJCOPY, OBJDUMP Tool options: CFLAGS, LDFLAGS When this makefile fragment runs, it will be passed TOPDIR which is the path to the root directory of the build. This makefile fragment may include ${TOPDIR}/.config to perform configuration specific settings. For example, the CFLAGS will most likely be different if CONFIG_DEBUG=y. defconfig -- This is a configuration file similar to the Linux configuration file. In contains varialble/value pairs like: CONFIG_VARIABLE=value This configuration file will be used at build time: (1) as a makefile fragment included in other makefiles, and (2) to generate include/nuttx/config.h which is included by most C files in the system. The following variables are recognized by the build (you may also include architecture/board-specific settings). Architecture selection: CONFIG_ARCH - Identifies the arch/ subdirectory CONFIG_ARCH_name - For use in C code CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory CONFIG_ARCH_CHIP_name - For use in C code CONFIG_ARCH_BOARD - Identifies the configs subdirectory and hence, the board that supports the particular chip or SoC. CONFIG_ARCH_BOARD_name - For use in C code Some architectures require a description of the the RAM configuration: CONFIG_DRAM_SIZE - Describes the installed DRAM. CONFIG_DRAM_START - The start address of DRAM (physical) CONFIG_DRAM_VSTART - The startaddress of DRAM (virtual) General OS setup CONFIG_EXAMPLE - identifies the subdirectory in examples that will be used in the build CONFIG_DEBUG - enables built-in debug options CONFIG_DEBUG_VERBOSE - enables verbose debug output CONFIG_HAVE_LOWPUTC - architecture supports low-level, boot time console output CONFIG_MM_REGIONS - If the architecture includes multiple regions of memory to allocate from, this specifies the number of memory regions that the memory manager must handle and enables the API mm_addregion(start, end); CONFIG_RR_INTERVAL - The round robin timeslice will be set this number of milliseconds; Round robin scheduling can be disabled by setting this value to zero. CONFIG_SCHED_INSTRUMENTATION - enables instrumentation in scheduler to monitor system performance CONFIG_TASK_NAME_SIZE - Spcifies that maximum size of a task name to save in the TCB. Useful if scheduler instrumentation is selected. Set to zero to disable. CONFIG_START_YEAR, CONFIG_START_MONTH, CONFIG_START_DAY - Used to initialize the internal time logic. CONFIG_JULIAN_TIME - Enables Julian time conversions CONFIG_DEV_CONSOLE - Set if architecture-specific logic provides /dev/console. Enables stdout, stderr, stdin. The following can be used to disable categories of APIs supported by the OS. If the compiler supports weak functions, then it should not be necessary to disable functions unless you want to restrict usage of those APIs. There are certain dependency relationships in these features. o mq_notify logic depends on signals to awaken tasks waiting for queues to become full or empty. o pthread_condtimedwait() depends on signals to wake up waiting tasks. CONFIG_DISABLE_CLOCK, CONFIG_DISABLE_POSIX_TIMERS, CONFIG_DISABLE_PTHREAD. CONFIG_DISABLE_SIGNALS, CONFIG_DISABLE_MQUEUE Misc libc settings CONFIG_NOPRINTF_FIELDWIDTH - sprintf-related logic is a little smaller if we do not support fieldwidthes Allow for architecture optimized implementations The architecture can provide optimized versions of the following to improve sysem performance CONFIG_ARCH_MEMCPY, CONFIG_ARCH_MEMCMP, CONFIG_ARCH_MEMMOVE CONFIG_ARCH_MEMSET, CONFIG_ARCH_STRCMP, CONFIG_ARCH_STRCPY CONFIG_ARCH_STRNCPY, CONFIG_ARCH_STRLEN, CONFIG_ARCH_BZERO CONFIG_ARCH_KMALLOC, CONFIG_ARCH_KZMALLOC, CONFIG_ARCH_KFREE Sizes of configurable things (0 disables) CONFIG_MAX_TASKS - The maximum number of simultaneously active tasks. This value must be a power of two. CONFIG_NPTHREAD_KEYS - The number of items of thread- specific data that can be retained CONFIG_NFILE_DESCRIPTORS - The maximum number of file descriptors (one for each open) CONFIG_NFILE_STREAMS - The maximum number of streams that can be fopen'ed CONFIG_NAME_MAX - The maximum size of a file name. CONFIG_STDIO_BUFFER_SIZE - Size of the buffer to allocate on fopen. (Only if CONFIG_NFILE_STREAMS > 0) CONFIG_NUNGET_CHARS - Number of characters that can be buffered by ungetc() (Only if CONFIG_NFILE_STREAMS > 0) CONFIG_PREALLOC_MQ_MSGS - The number of pre-allocated message structures. The system manages a pool of preallocated message structures to minimize dynamic allocations CONFIG_MQ_MAXMSGSIZE - Message structures are allocated with a fixed payload size given by this settin (does not include other message structure overhead. CONFIG_PREALLOC_WDOGS - The number of pre-allocated watchdog structures. The system manages a pool of preallocated watchdog structures to minimize dynamic allocations Stack and heap information CONFIG_BOOT_FROM_FLASH - Some configurations support XIP operation from FLASH. CONFIG_STACK_POINTER - The initial stack pointer CONFIG_PROC_STACK_SIZE - The size of the initial stack CONFIG_PTHREAD_STACK_MIN - Minimum pthread stack size CONFIG_PTHREAD_STACK_DEFAULT - Default pthread stack size CONFIG_HEAP_BASE - The beginning of the heap CONFIG_HEAP_SIZE - The size of the heap setenv.sh -- This is a script that you can include that will be installed at the toplevel of the directory structure and can be sourced to set any necessary environment variables. Supported Boards ^^^^^^^^^^^^^^^^ configs/sim A user-mode port of NuttX to the x86 Linux platform is available. The purpose of this port is primarily to support OS feature developement. This port does not support interrupts or a real timer (and hence no round robin scheduler) Otherwise, it is complete. configs/c5471evm This is a port to the Spectrum Digital C5471 evaluation board. The C5471 is a dual core processor from TI with an ARM7TDMI general purpose processor and a c54 SDP. NuttX runs on the ARM core and is built with with a GNU arm-elf toolchain*. This port is complete, verified, and included in the NuttX release. configs/mcu123-lpc214x This is a port to the mcu123.com lpc214x development board. This OS is also built with the the arm-elf toolchain* configs/ntosd-dm320 This port uses the Neuros OSD with a GNU arm-elf toolchain*: see http://wiki.neurostechnology.com/index.php/Developer_Welcome . NuttX operates on the ARM9EJS of this dual core processor. STATUS: This port is code complete, verified, and included in the NuttX 0.2.1 release. configs/mcu123-lpc214x This port is for the NXP LPC2148 as provided on the mcu123.com lpc214x development board. STATUS: This port is in progress and should be available in the nuttx-0.2.5 release. configs/m68322evb This is a work in progress for the venerable m68322evb board from Motorola. This OS is also built with the the arm-elf toolchain*. configs/pjrc-8051 8051 Microcontroller. This port uses the PJRC 87C52 development system and the SDCC toolchain. This port is not quite ready for prime time. Other ports for the for the TI TMS320DM270, M683222 and for MIPS are in various states of progress Configuring NuttX ^^^^^^^^^^^^^^^^^ Configuring NuttX requires only copying configs//Make.def to ${TOPDIR}/Make.defs configs//setenv.sh to ${TOPDIR}/setenv.sh configs//defconfig to ${TOPDIR}/.config There is a script that automates these steps. The following steps will accomplish the same configuration: cd tools ./configure.sh