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The following commit(s) were added to refs/heads/master by this push:
new f66c4a0733 Documentation/guides: add the guide:how to port.
f66c4a0733 is described below
commit f66c4a07330538b485e001be800c039a0e5f5c81
Author: Takuya Miyasita <[email protected]>
AuthorDate: Wed Dec 11 11:41:56 2024 +0900
Documentation/guides: add the guide:how to port.
I think the guy who wants to port NuttX is expected to understand NuttX
kernel code and related configurations,
but the getting enough knowledge needs to read the kernel codes deeply.
To reduce the time for NuttX beginner who wants to port,
I tried to make the guide (how to port) based on my porting journey.
---
.../guides/image/port_bootsequence-12.4.0.png | Bin 0 -> 75705 bytes
Documentation/guides/index.rst | 3 +-
Documentation/guides/port.rst | 75 ++
Documentation/guides/port_arm_cm4.rst | 969 +++++++++++++++++++++
Documentation/guides/port_bootsequence.rst | 13 +
.../guides/port_relatedkernelconfigrations.rst | 67 ++
6 files changed, 1126 insertions(+), 1 deletion(-)
diff --git a/Documentation/guides/image/port_bootsequence-12.4.0.png
b/Documentation/guides/image/port_bootsequence-12.4.0.png
new file mode 100644
index 0000000000..e6337ad416
Binary files /dev/null and
b/Documentation/guides/image/port_bootsequence-12.4.0.png differ
diff --git a/Documentation/guides/index.rst b/Documentation/guides/index.rst
index 32ca1ad1b8..52e2cced76 100644
--- a/Documentation/guides/index.rst
+++ b/Documentation/guides/index.rst
@@ -55,4 +55,5 @@ Guides
renode.rst
signal_events_interrupt_handlers.rst
signaling_sem_priority_inheritance.rst
- smaller_vector_tables.rst
\ No newline at end of file
+ smaller_vector_tables.rst
+ port.rst
\ No newline at end of file
diff --git a/Documentation/guides/port.rst b/Documentation/guides/port.rst
new file mode 100644
index 0000000000..377edbeaa4
--- /dev/null
+++ b/Documentation/guides/port.rst
@@ -0,0 +1,75 @@
+.. include:: /substitutions.rst
+===========================================
+How to port
+===========================================
+
+This guide explains "How to port NuttX".
+
+At this guide, the scope of porting is adding a new SoC or board directory,
+which can be built and has a working example that boots to the NuttShell (NSH).
+
+The goal of porting is to comfirm the booting NuttShell(NSH), the pass of
"ostest"
+and the timer.
+
+Porting a new SoC and board to NuttX requires modifications on arch,
+SoC and board directories.
+For the details,
+see :doc:`/quickstart/organization`,
+:doc:`/components/arch/index`,
+:doc:`/components/boards`.
+
+To port NuttX properly, we have to understand the boot sequence and
+related kernel configurations.
+Following links explain them, although these depend on
+specific kernel version and configurations.
+(To understand them, we have to read the code deeply.)
+
+.. toctree::
+ port_bootsequence.rst
+ port_relatedkernelconfigrations.rst
+
+About the implementation, the build system tells you minimal implementation of
SoC/Board directory,
+these implementations are almost done by copying and pasting from other
SoC/Board
+directory if there is the source code for the target HW IP in upstream.
+If there is not the source code in upstream, the porter has to implement it by
himself.
+
+Porting procedure
+=================
+
+At first, you have to read and execute :doc:`/quickstart/install` and
:doc:`/quickstart/compiling_make`.
+After that, try follwoing procedure.
+
++------+---------------+--------------------------------------------------------------------+
+| Step | Process | Comment
|
++------+---------------+--------------------------------------------------------------------+
+| 1 | Add the SoC |
|
++------+---------------+--------------------------------------------------------------------+
+| 2 | Add the Board | If the board was not sold in the market,
|
+| | | the board directory should be located out-of-tree.
|
+| | | For details see :doc:`/guides/customboards`.
|
+| | | And if you wanted to add own apps, see
:doc:`/guides/customapps`. |
++------+---------------+--------------------------------------------------------------------+
+| 3 | Configure | The configure needs to understand related kernel
configurations. |
+| | | see :doc:`/guides/port_relatedkernelconfigrations`.
|
++------+---------------+--------------------------------------------------------------------+
+| 4 | Compile | The compile tells you which source files are needed
in SoC/Board |
+| | | directory to pass the compile.
|
++------+---------------+--------------------------------------------------------------------+
+| 5 | Link | The link tells you which symbols are needed in
SoC/Board directory |
+| | | to pass the link.
|
++------+---------------+--------------------------------------------------------------------+
+| 6 | Implement | Do implement the symbols which are needed by the
link. |
++------+---------------+--------------------------------------------------------------------+
+| 7 | Verify | Do "apps/testing/ostest".
|
+| | | I think the pass of ostest is the one of proof for
proper porting. |
+| | | And check the timer implementation whether the kernel
could |
+| | | count the time accurately or not.
|
++------+---------------+--------------------------------------------------------------------+
+
+The result of porting procedure
+===============================
+
+Although these depend on specific kernel version.
+
+.. toctree::
+ port_arm_cm4.rst
diff --git a/Documentation/guides/port_arm_cm4.rst
b/Documentation/guides/port_arm_cm4.rst
new file mode 100644
index 0000000000..3bbfed2488
--- /dev/null
+++ b/Documentation/guides/port_arm_cm4.rst
@@ -0,0 +1,969 @@
+The case of ARM CM4 & cxd32xx @NuttX12.4.0
+==========================================
+
+Step1 : Add the SoC
+-------------------
+
+Create the SoC directory.
+
+.. code-block::
+
+ $ touch arch/arm/include/cxd32xx
+ $ touch arch/arm/src/cxd32xx
+
+Modify "arch/arm/Kconfig" to register the SoC directory.
+
+Add "Kconfig" and "Make.defs" for the SoC directory.
+
+.. code-block::
+
+ $ touch arch/arm/src/cxd32xx/Kconfig
+ $ touch arch/arm/src/cxd32xx/Make.defs
+
+For details about these files, see `apache/nuttx/pull/12441`_
+
+Step2 : Add the Board
+---------------------
+
+There are two ways about adding the Board directory.
+The one is in-of-tree, another one is out-of-tree.
+For details see :doc:`/guides/customboards`.
+And if you wanted to add own apps, see :doc:`/guides/customapps`.
+
+This time, the way of out-of-tree is selected.
+The directory structure is following :
+
+.. code-block::
+
+ apps/
+ nuttx/
+ out-of-tree/cxd32xx_boards
+
+Create the board : cb2sdb2 as the board of cxd32xx.
+
+.. code-block::
+
+ $ touch out-of-tree/cxd32xx_boards/cb2sdb2/configs/nsh
+ $ touch out-of-tree/cxd32xx_boards/cb2sdb2/include
+ $ touch out-of-tree/cxd32xx_boards/cb2sdb2/scripts
+ $ touch out-of-tree/cxd32xx_boards/cb2sdb2/src
+
+Add "Kconfig", "defconfig", "Make.defs" and "Makefile".
+
+.. code-block::
+
+ $ touch out-of-tree/cxd32xx_boards/cb2sdb2/Kconfig
+ $ touch out-of-tree/cxd32xx_boards/cb2sdb2/configs/nsh/defconfig
+ $ touch out-of-tree/cxd32xx_boards/cb2sdb2/scripts/Make.defs
+ $ touch out-of-tree/cxd32xx_boards/cb2sdb2/src/Makefile
+
+For details about these files, see :ref:`out-of-tree`.
+
+Step3 : Configure
+-----------------
+
+Now you can do configure by following commands.
+It is important to confirm these commands are working.
+
+.. code-block::
+
+ $ cd nuttx
+ $ ./tools/configure.sh -l ../out-of-tree/cxd32xx_boards/cb2sdb2/configs/nsh
+
+And you can do menuconfig by following command.
+
+.. code-block::
+
+ $ make menuconfig
+
+And you can do distclean by following command.
+
+.. code-block::
+
+ $ make distclean
+
+Step4 : Compile
+---------------
+
+Try to buid with the implementation of Step1-2, you would face the error as
following
+if you implemented only directory / Kconfig / Make.defs / Makefile / defconfig
about Step1-2.
+
+.. code-block::
+
+ $ make
+ Create version.h
+ LN: platform/board to /home/lassdk/workdir/nuttx1/apps/platform/dummy
+ In file included from
/home/lassdk/workdir/nuttx1/nuttx/include/nuttx/irq.h:37:0,
+ from
/home/lassdk/workdir/nuttx1/nuttx/include/nuttx/sched.h:40,
+ from
/home/lassdk/workdir/nuttx1/nuttx/include/nuttx/arch.h:87,
+ from ./clock/clock_initialize.c:37:
+ /home/lassdk/workdir/nuttx1/nuttx/include/arch/irq.h:43:27:
+ fatal error: arch/chip/irq.h: No such file or directory
+ compilation terminated.
+ ERROR: arm-none-eabi-gcc failed: 1
+ command: arm-none-eabi-gcc -MT ./clock_initialize.o -M
'-Wstrict-prototypes'
+ '-Wno-attributes' '-Wno-unknown-pragmas' '-Wno-psabi' '-Os'
+ '-fno-strict-aliasing' '-fomit-frame-pointer' '-fno-common' '-Wall'
+ '-Wshadow' '-Wundef'
+ '-ffunction-sections' '-fdata-sections' '-mlittle-endian'
+ '-march=armv7e-m' '-mtune=cortex-m4'
+ '-mfpu=fpv4-sp-d16' '-mfloat-abi=hard' '-mthumb' '-Wa,-mthumb'
+ '-Wa,-mimplicit-it=always' '-isystem'
+ '/home/lassdk/workdir/nuttx1/nuttx/include'
+ '-D__NuttX__' '-DNDEBUG' '-D__KERNEL__' '-pipe' '-I'
+ '/home/lassdk/workdir/nuttx1/nuttx/sched'
./clock/clock_initialize.c
+ make[2]: *** [/home/lassdk/workdir/nuttx1/nuttx/tools/Config.mk:230:
+ clock_initialize.ddc] Error 1
+ make[1]: *** [Makefile:71: .depend] Error 2
+ make: *** [tools/Unix.mk:619: pass2dep] Error 2
+
+Try to add "irq.h" with referring to cxd56xx and retry to build.
+This time, the build system will teach that you have to implement "chip.h" as
following.
+
+.. code-block::
+
+ $ make
+ CC: clock/clock_initialize.c In file included from
+ /home/lassdk/workdir/nuttx2/nuttx/include/arch/armv7-m/irq.h:37:0,
+ from
/home/lassdk/workdir/nuttx2/nuttx/include/arch/irq.h:56,
+ from
/home/lassdk/workdir/nuttx2/nuttx/include/nuttx/irq.h:37,
+ from
/home/lassdk/workdir/nuttx2/nuttx/include/nuttx/sched.h:40,
+ from
/home/lassdk/workdir/nuttx2/nuttx/include/nuttx/arch.h:87,
+ from clock/clock_initialize.c:37:
+ /home/lassdk/workdir/nuttx2/nuttx/include/arch/armv7-m/nvicpri.h:28:28
+ fatal error: arch/chip/chip.h: No such file or directory
+ compilation terminated.
+ make[1]: *** [Makefile:61: clock_initialize.o] Error 1
+ make: *** [tools/LibTargets.mk:65: sched/libsched.a] Error 2
+
+Continue this try and error until pass the Compiling.
+
+Step5 : Link
+------------
+
+After the pass of Compiling, you will get following error.
+To resolve this error, you have to implement the linker script.
+
+.. code-block::
+
+ $ make
+ make[1]: *** No rule to make target
+
'/home/lassdk/workdir/nuttx1/nuttx/../cxd32xx_boards/cb2sdb2/scripts/cb2sdb2.ld',
+ needed by
'/home/lassdk/workdir/nuttx1/nuttx/../cxd32xx_boards/cb2sdb2/scripts/cb2sdb2.ld.tmp'.
+ Stop.
+ make: *** [tools/Unix.mk:545: nuttx] Error 2
+
+Try to add the linker script with referring to some board(cxd56xx, lpc43xx,
etc) or :ref:`out-of-tree`
+and retry to build, the build system will teach that you have to implement
some symbols as following.
+
+.. code-block::
+
+ $ make
+ CPP:
/home/lassdk/workdir/nuttx1/nuttx/../cxd32xx_boards/cb2sdb2/scripts/cb2sdb2.ld->
+ /home/lassdk/workdir/nuttx1/nuttx/../boarLD: nuttx
+ arm-none-eabi-ld: warning: cannot find entry symbol __start; defaulting to
24011000
+
/home/lassdk/workdir/nuttx1/nuttx/staging/libarch.a(arm_vectors.o):(.vectors+0x4):
+ undefined reference to `__start'
+ /home/lassdk/workdir/nuttx1/nuttx/staging/libarch.a(arm_doirq.o): In
function `arm_doirq':
+ arm_doirq.c:(.text.arm_doirq+0x12): undefined reference to `arm_ack_irq'
+ /home/lassdk/workdir/nuttx1/nuttx/staging/libdrivers.a(syslog_channel.o):
+ In function `syslog_default_putc':
+ syslog_channel.c:(.text.syslog_default_putc+0x2): undefined reference to
`up_putc'
+ /home/lassdk/workdir/nuttx1/nuttx/staging/libarch.a(arm_nputs.o): In
function `up_nputs':
+ arm_nputs.c:(.text.up_nputs+0x10): undefined reference to `up_putc'
+ make[1]: *** [Makefile:197: nuttx] Error 1
+ make: *** [tools/Unix.mk:545: nuttx] Error 2
+
+Step6 : Implement
+-----------------
+
+There are some implementation items, major items are bellow listed. To pass
the Linking,
+try to implement these symboles.
+
++-----------------+------------------------+--------------------------------------------------------------------+
+| Category | Item | Comment
|
++-----------------+------------------------+--------------------------------------------------------------------+
+| SoC directory | entory point : __start | `apache/nuttx/pull/12441`_
|
++ +------------------------+
+
+| | Serial Driver |
|
++ +------------------------+
+
+| | IDLE task stack |
|
++ +------------------------+
+
+| | INTC |
|
++ +------------------------+
+
+| | Timer |
|
++-----------------+------------------------+------------------------------------------------+-------------------+
+| Board directory | board_app_initialize |
:doc:`/applications/nsh/customizing` |:ref:`out-of-tree` |
++
+------------------------+------------------------------------------------+
|
+| |<arch>_board_initialize | `sched/Kconfig`_
:BOARD_<EARLY/LATE>_INITIALIZE| |
++-----------------+------------------------+------------------------------------------------+-------------------+
+
+.. _apache/nuttx/pull/12441: https://github.com/apache/nuttx/pull/12441
+.. _sched/Kconfig: https://github.com/apache/nuttx/blob/master/sched/Kconfig
+
+If got the pass of Linking, you would see follwoing result.
+
+.. code-block::
+
+ $ make
+ Create version.h
+ LN: platform/board to /home/lassdk/workdir/nuttx2/apps/platform/dummy
+ Register: nsh
+ Register: sh
+ CPP:
/home/lassdk/workdir/nuttx2/nuttx/../boards/cb2sdb2/scripts/cb2sdb2.ld->
+ /home/lassdk/workdir/nuttx2/nuttx/../boarLD: nuttx
+
+Step7 : Verify
+--------------
+
+To execute and debug on the evalutaion board, add following configurations.
+
+.. code-block::
+
+ CONFIG_RAW_BINARY=y
+ CONFIG_DEBUG_SYMBOLS=y
+
+If your implementations were good, you would see following logs.
+
+.. code-block::
+
+ NuttShell (NSH) NuttX-12.4.0
+ nsh>
+ nsh>
+ nsh>
+
+After comfirming to boot NuttShell(NSH), try to execute "apps/testing/ostest".
+The "apps/testing/ostest" needs following configurations.
+
+.. code-block::
+
+ CONFIG_BUILTIN=y
+ CONFIG_NSH_BUILTIN_APPS=y
+ CONFIG_SCHED_WAITPID=y
+ CONFIG_TESTING_OSTEST=y
+
+And one more test is recomended to check the timer implementation whether
+the kernel could count the time accurately or not.
+I checked it by following code. About the function : cxd32_timerget(),
+see `apache/nuttx/pull/12441`_
+
+.. code-block::
+
+ extern uint32_t cxd32_timerget(void);
+
+ {
+ uint32_t pre;
+ uint32_t post;
+
+ pre = cxd32_timerget();
+ sleep(1);
+ post = cxd32_timerget();
+ printf("pre:%lu post:%lu exptect:1sec\n", pre, post);
+
+ pre = cxd32_timerget();
+ sleep(10);
+ post = cxd32_timerget();
+ printf("pre:%lu post:%lu exptect:10sec\n", pre, post);
+ }
+
+.. _out-of-tree:
+
+Appendix : out-of-tree code
+---------------------------
+
+.. code-block::
+
+ diff --git a/cxd32xx_apps/Make.defs b/cxd32xx_apps/Make.defs
+ new file mode 100644
+ index 0000000..2d6b86e
+ --- /dev/null
+ +++ b/cxd32xx_apps/Make.defs
+ @@ -0,0 +1 @@
+ +include $(wildcard $(APPDIR)/cxd32xx_apps/*/Make.defs)
+ diff --git a/cxd32xx_apps/Makefile b/cxd32xx_apps/Makefile
+ new file mode 100644
+ index 0000000..e451b29
+ --- /dev/null
+ +++ b/cxd32xx_apps/Makefile
+ @@ -0,0 +1,3 @@
+ +MENUDESC = "cxd32xx_apps"
+ +
+ +include $(APPDIR)/Directory.mk
+ diff --git a/cxd32xx_apps/hello/Kconfig b/cxd32xx_apps/hello/Kconfig
+ new file mode 100644
+ index 0000000..7f0b41e
+ --- /dev/null
+ +++ b/cxd32xx_apps/hello/Kconfig
+ @@ -0,0 +1,29 @@
+ +#
+ +# For a description of the syntax of this configuration file,
+ +# see the file kconfig-language.txt in the NuttX tools repository.
+ +#
+ +
+ +config CXD32XX_APPS_HELLO
+ + tristate "CXD32XX Hello App"
+ + default n
+ + ---help---
+ + Enable the CXD32XX Hello App
+ +
+ +if CXD32XX_APPS_HELLO
+ +
+ +config CXD32XX_APPS_HELLO_PROGNAME
+ + string "Program name"
+ + default "hello"
+ + ---help---
+ + This is the name of the program that will be used when the NSH ELF
+ + program is installed.
+ +
+ +config CXD32XX_APPS_HELLO_PRIORITY
+ + int "CXD32XX Hello task priority"
+ + default 100
+ +
+ +config CXD32XX_APPS_HELLO_STACKSIZE
+ + int "CXD32XX Hello stack size"
+ + default DEFAULT_TASK_STACKSIZE
+ +
+ +endif
+ diff --git a/cxd32xx_apps/hello/Make.defs b/cxd32xx_apps/hello/Make.defs
+ new file mode 100644
+ index 0000000..730329a
+ --- /dev/null
+ +++ b/cxd32xx_apps/hello/Make.defs
+ @@ -0,0 +1,3 @@
+ +ifneq ($(CONFIG_CXD32XX_APPS_HELLO),)
+ +CONFIGURED_APPS += $(APPDIR)/cxd32xx_apps/hello
+ +endif
+ diff --git a/cxd32xx_apps/hello/Makefile b/cxd32xx_apps/hello/Makefile
+ new file mode 100644
+ index 0000000..b3438e1
+ --- /dev/null
+ +++ b/cxd32xx_apps/hello/Makefile
+ @@ -0,0 +1,14 @@
+ +include $(APPDIR)/Make.defs
+ +
+ +# Custom Hello built-in application info
+ +
+ +PROGNAME = $(CONFIG_CXD32XX_APPS_HELLO_PROGNAME)
+ +PRIORITY = $(CONFIG_CXD32XX_APPS_HELLO_PRIORITY)
+ +STACKSIZE = $(CONFIG_CXD32XX_APPS_HELLO_STACKSIZE)
+ +MODULE = $(CONFIG_CXD32XX_APPS_HELLO)
+ +
+ +# Custom Hello
+ +
+ +MAINSRC = hello.c
+ +
+ +include $(APPDIR)/Application.mk
+ diff --git a/cxd32xx_apps/hello/hello.c b/cxd32xx_apps/hello/hello.c
+ new file mode 100644
+ index 0000000..b14a762
+ --- /dev/null
+ +++ b/cxd32xx_apps/hello/hello.c
+ @@ -0,0 +1,24 @@
+
+/****************************************************************************
+ + * cxd32xx_apps/hello/hello.c
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Included Files
+ +
****************************************************************************/
+ +
+ +#include <nuttx/config.h>
+ +#include <stdio.h>
+ +
+
+/****************************************************************************
+ + * Public Functions
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * hello_main
+ +
****************************************************************************/
+ +
+ +int main(int argc, FAR char *argv[])
+ +{
+ + printf("Hello, World!!\n");
+ + return 0;
+ +}
+ diff --git a/cxd32xx_apps/time/Kconfig b/cxd32xx_apps/time/Kconfig
+ new file mode 100644
+ index 0000000..64e7591
+ --- /dev/null
+ +++ b/cxd32xx_apps/time/Kconfig
+ @@ -0,0 +1,28 @@
+ +#
+ +# For a description of the syntax of this configuration file,
+ +# see the file kconfig-language.txt in the NuttX tools repository.
+ +#
+ +
+ +config CXD32XX_APPS_TIME
+ + tristate "CXD32XX Time App"
+ + default n
+ + ---help---
+ + Enable the CXD32XX Time App
+ +
+ +if CXD32XX_APPS_HELLO
+ +
+ +config CXD32XX_APPS_TIME_PROGNAME
+ + string "Program name"
+ + default "time"
+ + ---help---
+ + This apps measures the elasped time of sleep system call to confirm
the timer implementation.
+ +
+ +config CXD32XX_APPS_TIME_PRIORITY
+ + int "CXD32XX Time task priority"
+ + default 100
+ +
+ +config CXD32XX_APPS_TIME_STACKSIZE
+ + int "CXD32XX Time stack size"
+ + default DEFAULT_TASK_STACKSIZE
+ +
+ +endif
+ diff --git a/cxd32xx_apps/time/Make.defs b/cxd32xx_apps/time/Make.defs
+ new file mode 100644
+ index 0000000..cdfb4cc
+ --- /dev/null
+ +++ b/cxd32xx_apps/time/Make.defs
+ @@ -0,0 +1,3 @@
+ +ifneq ($(CONFIG_CXD32XX_APPS_TIME),)
+ +CONFIGURED_APPS += $(APPDIR)/cxd32xx_apps/time
+ +endif
+ diff --git a/cxd32xx_apps/time/Makefile b/cxd32xx_apps/time/Makefile
+ new file mode 100644
+ index 0000000..94c9007
+ --- /dev/null
+ +++ b/cxd32xx_apps/time/Makefile
+ @@ -0,0 +1,14 @@
+ +include $(APPDIR)/Make.defs
+ +
+ +# Custom Hello built-in application info
+ +
+ +PROGNAME = $(CONFIG_CXD32XX_APPS_TIME_PROGNAME)
+ +PRIORITY = $(CONFIG_CXD32XX_APPS_TIME_PRIORITY)
+ +STACKSIZE = $(CONFIG_CXD32XX_APPS_TIME_STACKSIZE)
+ +MODULE = $(CONFIG_CXD32XX_APPS_TIME)
+ +
+ +# Custom Hello
+ +
+ +MAINSRC = time.c
+ +
+ +include $(APPDIR)/Application.mk
+ diff --git a/cxd32xx_apps/time/time.c b/cxd32xx_apps/time/time.c
+ new file mode 100644
+ index 0000000..9775ef2
+ --- /dev/null
+ +++ b/cxd32xx_apps/time/time.c
+ @@ -0,0 +1,41 @@
+
+/****************************************************************************
+ + * cxd32xx_apps/time/time.c
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Included Files
+ +
****************************************************************************/
+ +
+ +#include <nuttx/config.h>
+ +#include <stdio.h>
+ +
+
+/****************************************************************************
+ + * Public Functions
+ +
****************************************************************************/
+ +
+ +extern uint32_t cxd32_timerget(void);
+ +
+
+/****************************************************************************
+ + * hello_main
+ +
****************************************************************************/
+ +
+ +int main(int argc, FAR char *argv[])
+ +{
+ + uint32_t pre;
+ + uint32_t post;
+ +
+ + printf("measures the elasped time of sleep system call to confirm \
+ + the timer implementation.\n");
+ +
+ + pre = cxd32_timerget();
+ + sleep(1);
+ + post = cxd32_timerget();
+ + printf("pre:%lu post:%lu exptect:1sec\n", pre, post);
+ +
+ + pre = cxd32_timerget();
+ + sleep(10);
+ + post = cxd32_timerget();
+ + printf("pre:%lu post:%lu exptect:10sec\n", pre, post);
+ +
+ + return 0;
+ +}
+ diff --git a/cxd32xx_boards/cb2sdb2/Kconfig b/cxd32xx_boards/cb2sdb2/Kconfig
+ new file mode 100644
+ index 0000000..f72f3c0
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/Kconfig
+ @@ -0,0 +1,4 @@
+ +#
+ +# For a description of the syntax of this configuration file,
+ +# see the file kconfig-language.txt in the NuttX tools repository.
+ +#
+ diff --git a/cxd32xx_boards/cb2sdb2/configs/nsh/defconfig
b/cxd32xx_boards/cb2sdb2/configs/nsh/defconfig
+ new file mode 100644
+ index 0000000..1d4c3e2
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/configs/nsh/defconfig
+ @@ -0,0 +1,38 @@
+ +#
+ +# This file is autogenerated: PLEASE DO NOT EDIT IT.
+ +#
+ +# You can use "make menuconfig" to make any modifications to the installed
.config file.
+ +# You can then do "make savedefconfig" to generate a new defconfig file
that includes your
+ +# modifications.
+ +#
+ +CONFIG_ARCH="arm"
+ +CONFIG_ARCH_CORTEXM4=y
+ +CONFIG_ARCH_FPU=y
+ +CONFIG_ARCH_CHIP="cxd32xx"
+ +CONFIG_ARCH_CHIP_CXD32XX=y
+ +CONFIG_ARCH_BOARD_CUSTOM=y
+ +CONFIG_ARCH_BOARD_CUSTOM_DIR="../out-of-tree/cxd32xx_boards/cb2sdb2"
+ +CONFIG_ARCH_BOARD_CUSTOM_DIR_RELPATH=y
+ +CONFIG_ARCH_BOARD_CUSTOM_NAME="cb2sdb2"
+ +CONFIG_INIT_ENTRYPOINT="nsh_main"
+ +CONFIG_UART0_SERIAL_CONSOLE=y
+ +CONFIG_SYSTEM_NSH=y
+ +CONFIG_RAM_START=0x00800000
+ +CONFIG_RAM_SIZE=244736
+ +CONFIG_ARCH_RAMVECTORS=y
+ +CONFIG_RAW_BINARY=y
+ +CONFIG_DEBUG_SYMBOLS=y
+ +CONFIG_UART_PL011=y
+ +CONFIG_UART0_PL011=y
+ +CONFIG_UART0_BASE=0x42104000
+ +CONFIG_UART0_IRQ=89
+ +CONFIG_UART0_CLK_FREQ=32000000
+ +CONFIG_UART_PL011_PLATFORMIF=y
+ +CONFIG_BUILTIN=y
+ +CONFIG_NSH_BUILTIN_APPS=y
+ +CONFIG_SCHED_WAITPID=y
+ +CONFIG_TESTING_OSTEST=y
+ +CONFIG_FS_PROCFS=y
+ +CONFIG_STACK_COLORATION=y
+ +CONFIG_CXD32XX_APPS_HELLO=y
+ +CONFIG_CXD32XX_APPS_TIME=y
+ diff --git a/cxd32xx_boards/cb2sdb2/include/board.h
b/cxd32xx_boards/cb2sdb2/include/board.h
+ new file mode 100644
+ index 0000000..eae687e
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/include/board.h
+ @@ -0,0 +1,54 @@
+
+/****************************************************************************
+ + * cxd32xx_boards/cb2sdb2/include/board.h
+ + *
+ + * Licensed to the Apache Software Foundation (ASF) under one or more
+ + * contributor license agreements. See the NOTICE file distributed with
+ + * this work for additional information regarding copyright ownership. The
+ + * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ + * "License"); you may not use this file except in compliance with the
+ + * License. You may obtain a copy of the License at
+ + *
+ + * http://www.apache.org/licenses/LICENSE-2.0
+ + *
+ + * Unless required by applicable law or agreed to in writing, software
+ + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ + * License for the specific language governing permissions and limitations
+ + * under the License.
+ + *
+ +
****************************************************************************/
+ +
+ +#ifndef __CXD32XX_BOARDS_CB2SDB2_INCLUDE_BOARD_H
+ +#define __CXD32XX_BOARDS_CB2SDB2_INCLUDE_BOARD_H
+ +
+
+/****************************************************************************
+ + * Included Files
+ +
****************************************************************************/
+ +
+ +#include <nuttx/config.h>
+ +#include <nuttx/irq.h>
+ +#include <sys/boardctl.h>
+ +#include <stdbool.h>
+ +
+
+/****************************************************************************
+ + * Pre-processor Definitions
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Public Types
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Public Function Prototypes
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Name: cxd32_boardinitialize
+ + *
+ + * Description:
+ + *
+ +
****************************************************************************/
+ +
+ +void cxd32_boardinitialize(void);
+ +
+ +#endif /* __CXD32XX_BOARDS_CB2SDB2_INCLUDE_BOARD_H */
+ diff --git a/cxd32xx_boards/cb2sdb2/scripts/Make.defs
b/cxd32xx_boards/cb2sdb2/scripts/Make.defs
+ new file mode 100644
+ index 0000000..4986d69
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/scripts/Make.defs
+ @@ -0,0 +1,40 @@
+ +############################################################################
+ +# cxd32xx_boards/cb2sdb2/scripts/Make.defs
+ +#
+ +# Licensed to the Apache Software Foundation (ASF) under one or more
+ +# contributor license agreements. See the NOTICE file distributed with
+ +# this work for additional information regarding copyright ownership. The
+ +# ASF licenses this file to you under the Apache License, Version 2.0 (the
+ +# "License"); you may not use this file except in compliance with the
+ +# License. You may obtain a copy of the License at
+ +#
+ +# http://www.apache.org/licenses/LICENSE-2.0
+ +#
+ +# Unless required by applicable law or agreed to in writing, software
+ +# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ +# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ +# License for the specific language governing permissions and limitations
+ +# under the License.
+ +#
+ +############################################################################
+ +
+ +include $(TOPDIR)/.config
+ +include $(TOPDIR)/tools/Config.mk
+ +include $(TOPDIR)/arch/arm/src/armv7-m/Toolchain.defs
+ +
+ +LDSCRIPT = cb2sdb2.ld
+ +
+ +ARCHSCRIPT += $(BOARD_DIR)$(DELIM)scripts$(DELIM)$(LDSCRIPT)
+ +
+ +ARCHPICFLAGS = -fpic -msingle-pic-base -mpic-register=r10
+ +
+ +CFLAGS := $(ARCHCFLAGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARCHINCLUDES)
$(ARCHDEFINES) $(EXTRAFLAGS) -pipe
+ +CPICFLAGS = $(ARCHPICFLAGS) $(CFLAGS)
+ +CXXFLAGS := $(ARCHCXXFLAGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS)
$(ARCHXXINCLUDES) $(ARCHDEFINES) $(EXTRAFLAGS) -pipe
+ +CXXPICFLAGS = $(ARCHPICFLAGS) $(CXXFLAGS)
+ +CPPFLAGS := $(ARCHINCLUDES) $(ARCHDEFINES) $(EXTRAFLAGS)
+ +AFLAGS := $(CFLAGS) -D__ASSEMBLY__
+ +
+ +NXFLATLDFLAGS1 = -r -d -warn-common
+ +NXFLATLDFLAGS2 = $(NXFLATLDFLAGS1)
-T$(TOPDIR)/binfmt/libnxflat/gnu-nxflat-pcrel.ld -no-check-sections
+ +LDNXFLATFLAGS = -e main -s 2048
+ diff --git a/cxd32xx_boards/cb2sdb2/scripts/cb2sdb2.ld
b/cxd32xx_boards/cb2sdb2/scripts/cb2sdb2.ld
+ new file mode 100644
+ index 0000000..34ac8ac
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/scripts/cb2sdb2.ld
+ @@ -0,0 +1,99 @@
+
+/****************************************************************************
+ + * cxd32xx_boards/cb2sdb2/scripts/cb2sdb2.ld
+ + *
+ + * Licensed to the Apache Software Foundation (ASF) under one or more
+ + * contributor license agreements. See the NOTICE file distributed with
+ + * this work for additional information regarding copyright ownership. The
+ + * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ + * "License"); you may not use this file except in compliance with the
+ + * License. You may obtain a copy of the License at
+ + *
+ + * http://www.apache.org/licenses/LICENSE-2.0
+ + *
+ + * Unless required by applicable law or agreed to in writing, software
+ + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ + * License for the specific language governing permissions and limitations
+ + * under the License.
+ + *
+ +
****************************************************************************/
+ +
+ +INCLUDE ../../../../out-of-tree/cxd32xx_boards/cb2sdb2/scripts/memmap.ld
+ +
+ +OUTPUT_ARCH(arm)
+ +ENTRY(__start) /* Treat __start as the anchor for dead code
stripping */
+ +EXTERN(_vectors) /* Force the vectors to be included in the output */
+ +SECTIONS
+ +{
+ + .text : {
+ + _stext = ABSOLUTE(.);
+ + *(.entry)
+ + *(.vectors)
+ + *(.text .text.*)
+ + *(.fixup)
+ + *(.gnu.warning)
+ + *(.rodata .rodata.*)
+ + *(.gnu.linkonce.t.*)
+ + *(.glue_7)
+ + *(.glue_7t)
+ + *(.got)
+ + *(.gcc_except_table)
+ + *(.gnu.linkonce.r.*)
+ + _etext = ABSOLUTE(.);
+ + } > flash_Cached
+ +
+ + .init_section : {
+ + _sinit = ABSOLUTE(.);
+ + KEEP(*(SORT_BY_INIT_PRIORITY(.init_array.*)
SORT_BY_INIT_PRIORITY(.ctors.*)))
+ + KEEP(*(.init_array .ctors))
+ + _einit = ABSOLUTE(.);
+ + } > flash_Cached
+ +
+ + .ARM.extab : {
+ + *(.ARM.extab*)
+ + } > flash_Cached
+ +
+ + __exidx_start = ABSOLUTE(.);
+ + .ARM.exidx : {
+ + *(.ARM.exidx*)
+ + } > flash_Cached
+ + __exidx_end = ABSOLUTE(.);
+ +
+ + _eronly = ABSOLUTE(.);
+ +
+ + .data : {
+ + _sdata = ABSOLUTE(.);
+ + *(.data .data.*)
+ + *(.gnu.linkonce.d.*)
+ + CONSTRUCTORS
+ + . = ALIGN(4);
+ + _edata = ABSOLUTE(.);
+ + } > sram AT > flash_Cached
+ +
+ + .ram_vectors : {
+ + *(.ram_vectors)
+ + } > sram
+ +
+ + .bss : { /* BSS */
+ + _sbss = ABSOLUTE(.);
+ + *(.bss .bss.*)
+ + *(.gnu.linkonce.b.*)
+ + *(COMMON)
+ + . = ALIGN(4);
+ + _ebss = ABSOLUTE(.);
+ + } > sram
+ +
+ + /* Stabs debugging sections. */
+ + .stab 0 : { *(.stab) }
+ + .stabstr 0 : { *(.stabstr) }
+ + .stab.excl 0 : { *(.stab.excl) }
+ + .stab.exclstr 0 : { *(.stab.exclstr) }
+ + .stab.index 0 : { *(.stab.index) }
+ + .stab.indexstr 0 : { *(.stab.indexstr) }
+ + .comment 0 : { *(.comment) }
+ + .debug_abbrev 0 : { *(.debug_abbrev) }
+ + .debug_info 0 : { *(.debug_info) }
+ + .debug_line 0 : { *(.debug_line) }
+ + .debug_pubnames 0 : { *(.debug_pubnames) }
+ + .debug_aranges 0 : { *(.debug_aranges) }
+ +}
+ diff --git a/cxd32xx_boards/cb2sdb2/scripts/memmap.ld
b/cxd32xx_boards/cb2sdb2/scripts/memmap.ld
+ new file mode 100644
+ index 0000000..848f336
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/scripts/memmap.ld
+ @@ -0,0 +1,13 @@
+
+/****************************************************************************
+ + * Automatically generated file; DO NOT EDIT.
+ +
****************************************************************************/
+ +
+ +MEMORY
+ +{
+ + sram (rwx) : ORIGIN = 0x00800000, LENGTH = 0x0003BC00
+ + sram_erw (rw) : ORIGIN = 0x0083BC00, LENGTH = 0x00001000
+ + sram_frw (rw) : ORIGIN = 0x0083CC00, LENGTH = 0x00002000
+ + sram_prt (rw) : ORIGIN = 0x0083EC00, LENGTH = 0x00001000
+ + sram_lib (rwx) : ORIGIN = 0x0083FC00, LENGTH = 0x00000400
+ + flash_Cached (rx) : ORIGIN = 0x24010000, LENGTH = 0x0013F000
+ +}
+ diff --git a/cxd32xx_boards/cb2sdb2/src/Makefile
b/cxd32xx_boards/cb2sdb2/src/Makefile
+ new file mode 100644
+ index 0000000..f8b1cd8
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/src/Makefile
+ @@ -0,0 +1,25 @@
+ +############################################################################
+ +# cxd32xx_boards/cb2sdb2/src/Makefile
+ +#
+ +# Licensed to the Apache Software Foundation (ASF) under one or more
+ +# contributor license agreements. See the NOTICE file distributed with
+ +# this work for additional information regarding copyright ownership. The
+ +# ASF licenses this file to you under the Apache License, Version 2.0 (the
+ +# "License"); you may not use this file except in compliance with the
+ +# License. You may obtain a copy of the License at
+ +#
+ +# http://www.apache.org/licenses/LICENSE-2.0
+ +#
+ +# Unless required by applicable law or agreed to in writing, software
+ +# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ +# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ +# License for the specific language governing permissions and limitations
+ +# under the License.
+ +#
+ +############################################################################
+ +
+ +include $(TOPDIR)/Make.defs
+ +
+ +CSRCS += cxd32_appinit.c cxd32_boot.c
+ +
+ +include $(TOPDIR)/boards/Board.mk
+ diff --git a/cxd32xx_boards/cb2sdb2/src/cxd32_appinit.c
b/cxd32xx_boards/cb2sdb2/src/cxd32_appinit.c
+ new file mode 100644
+ index 0000000..c1bef5f
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/src/cxd32_appinit.c
+ @@ -0,0 +1,90 @@
+
+/****************************************************************************
+ + * cxd32xx_boards/cb2sdb2/src/cxd32_appinit.c
+ + *
+ + * Licensed to the Apache Software Foundation (ASF) under one or more
+ + * contributor license agreements. See the NOTICE file distributed with
+ + * this work for additional information regarding copyright ownership. The
+ + * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ + * "License"); you may not use this file except in compliance with the
+ + * License. You may obtain a copy of the License at
+ + *
+ + * http://www.apache.org/licenses/LICENSE-2.0
+ + *
+ + * Unless required by applicable law or agreed to in writing, software
+ + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ + * License for the specific language governing permissions and limitations
+ + * under the License.
+ + *
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Included Files
+ +
****************************************************************************/
+ +
+ +#include <nuttx/config.h>
+ +#include <nuttx/compiler.h>
+ +
+ +#include <sys/types.h>
+ +#include <nuttx/board.h>
+ +
+
+/****************************************************************************
+ + * Pre-processor Definitions
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Public Functions
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Name: board_app_initialize
+ + *
+ + * Description:
+ + * Perform application specific initialization. This function is never
+ + * called directly from application code, but only indirectly via the
+ + * (non-standard) boardctl() interface using the command BOARDIOC_INIT.
+ + *
+ + * Input Parameters:
+ + * arg - The boardctl() argument is passed to the board_app_initialize()
+ + * implementation without modification. The argument has no
+ + * meaning to NuttX; the meaning of the argument is a contract
+ + * between the board-specific initialization logic and the
+ + * matching application logic. The value could be such things as a
+ + * mode enumeration value, a set of DIP switch switch settings, a
+ + * pointer to configuration data read from a file or serial FLASH,
+ + * or whatever you would like to do with it. Every implementation
+ + * should accept zero/NULL as a default configuration.
+ + *
+ + * Returned Value:
+ + * Zero (OK) is returned on success; a negated errno value is returned on
+ + * any failure to indicate the nature of the failure.
+ + *
+ +
****************************************************************************/
+ +
+ +int board_app_initialize(uintptr_t arg)
+ +{
+ + /* XXX : it will be implemented later */
+ +
+ + return OK;
+ +}
+ +
+
+/****************************************************************************
+ + * Name: board_late_initialize
+ + *
+ + * Description:
+ + * If CONFIG_BOARD_LATE_INITIALIZE is selected, then an additional
+ + * initialization call will be performed in the boot-up sequence to a
+ + * function called board_late_initialize(). board_late_initialize()
+ + * will be called immediately after up_initialize() is called and just
+ + * before the initial application is started. This additional
+ + * initialization phase may be used, for example, to initialize board-
+ + * specific device drivers.
+ + *
+ +
****************************************************************************/
+ +
+ +#ifdef CONFIG_BOARD_LATE_INITIALIZE
+ +void weak_function board_late_initialize(void)
+ +{
+ + /* XXX : it will be implemented later */
+ +}
+ +#endif
+ diff --git a/cxd32xx_boards/cb2sdb2/src/cxd32_boot.c
b/cxd32xx_boards/cb2sdb2/src/cxd32_boot.c
+ new file mode 100644
+ index 0000000..edf4328
+ --- /dev/null
+ +++ b/cxd32xx_boards/cb2sdb2/src/cxd32_boot.c
+ @@ -0,0 +1,56 @@
+
+/****************************************************************************
+ + * cxd32xx_boards/cb2sdb2/src/cxd32_boot.c
+ + *
+ + * Licensed to the Apache Software Foundation (ASF) under one or more
+ + * contributor license agreements. See the NOTICE file distributed with
+ + * this work for additional information regarding copyright ownership. The
+ + * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ + * "License"); you may not use this file except in compliance with the
+ + * License. You may obtain a copy of the License at
+ + *
+ + * http://www.apache.org/licenses/LICENSE-2.0
+ + *
+ + * Unless required by applicable law or agreed to in writing, software
+ + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ + * License for the specific language governing permissions and limitations
+ + * under the License.
+ + *
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Included Files
+ +
****************************************************************************/
+ +
+ +#include <nuttx/config.h>
+ +
+ +#include <debug.h>
+ +
+ +#include <nuttx/board.h>
+ +#include <arch/board/board.h>
+ +
+ +#include "arm_internal.h"
+ +
+
+/****************************************************************************
+ + * Pre-processor Definitions
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Private Functions
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Public Functions
+ +
****************************************************************************/
+ +
+
+/****************************************************************************
+ + * Name: cxd32_boardinitialize
+ + *
+ + * Description:
+ + *
+ +
****************************************************************************/
+ +
+ +void cxd32_boardinitialize(void)
+ +{
+ + /* XXX : it will be implemented later */
+ +}
+
diff --git a/Documentation/guides/port_bootsequence.rst
b/Documentation/guides/port_bootsequence.rst
new file mode 100644
index 0000000000..6887005bec
--- /dev/null
+++ b/Documentation/guides/port_bootsequence.rst
@@ -0,0 +1,13 @@
+The diagram of boot sequence
+============================
+
+The premise of this sequence diagram is NuttX12.4.0, cxd56xx, non-SMP and Flat
build.
+
+The beginning of boot sequence is __start().
+__start() will call nx_start(). nx_start() will initialize the kernel and call
nsh_main().
+nsh_main() will execute NuttShell(NSH).
+nx_start() is NuttX standard function, but the behavior depends on some kernel
configurations.
+For example, the calling nsh_main() is also configurable.
+About related kernel configurations, see
:doc:`/guides/port_relatedkernelconfigrations`.
+
+.. image:: image/port_bootsequence-12.4.0.png
diff --git a/Documentation/guides/port_relatedkernelconfigrations.rst
b/Documentation/guides/port_relatedkernelconfigrations.rst
new file mode 100644
index 0000000000..ca1d22be42
--- /dev/null
+++ b/Documentation/guides/port_relatedkernelconfigrations.rst
@@ -0,0 +1,67 @@
+The list of related kernel configurations
+=========================================
+
+The premise of this list : NuttX12.4.0, cxd56xx, non-SMP and Flat build.
+
+I found following kernel configurations by analyzing the boot sequence.
+I think it is good to consider them,
+although almost of them might be set as default.
+
++-----------------+-------------------------------+------------------+
+| Category | Item | Comment |
++-----------------+-------------------------------+------------------+
+| Memory Map | CONFIG_RAM_START | `arch/Kconfig`_ |
++ +-------------------------------+ +
+| | CONFIG_RAM_SIZE | |
++ +-------------------------------+------------------+
+| | CONFIG_IDLETHREAD_STACKSIZE | `sched/Kconfig`_ |
++ +-------------------------------+------------------+
+| | CONFIG_MM_REGIONS | `mm/Kconfig`_ |
++ +-------------------------------+------------------+
+| | CONFIG_ARCH_HAVE_EXTRA_HEAPS | `arch/Kconfig`_ |
++-----------------+-------------------------------+------------------+
+| Interrupt | CONFIG_ARCH_RAMVECTORS | `arch/Kconfig`_ |
++ +-------------------------------+ +
+| | CONFIG_ARCH_IRQPRIO | |
++ +-------------------------------+ +
+| | CONFIG_ARCH_INTERRUPTSTACK | |
++ +-------------------------------+ +
+| | CONFIG_SUPPRESS_INTERRUPTS | |
++ +-------------------------------+ +
+| | CONFIG_SUPPRESS_TIMER_INTS | |
++ +-------------------------------+------------------+
+| | CONFIG_IRQCHAIN | `sched/Kconfig`_ |
++-----------------+-------------------------------+------------------+
+| Timer | CONFIG_SYSTEMTICK_EXTCLK | `sched/Kconfig`_ |
++ +-------------------------------+ +
+| | CONFIG_SCHED_TICKLESS | |
++-----------------+-------------------------------+------------------+
+| Serial | CONFIG_STANDARD_SERIAL | `serial/Kconfig`_|
++ +-------------------------------+------------------+
+| | CONFIG_DEV_CONSOLE | `sched/Kconfig`_ |
++-----------------+-------------------------------+------------------+
+| Board | CONFIG_BOARD_EARLY_INITIALIZE | `sched/Kconfig`_ |
++ +-------------------------------+ +
+| | CONFIG_BOARD_LATE_INITIALIZE | |
++ +-------------------------------+ +
+| | CONFIG_INIT_ENTRYPOINT | |
++-----------------+-------------------------------+------------------+
+| POSIX API | CONFIG_PRIORITY_INHERITANCE | `sched/Kconfig`_ |
++ +-------------------------------+ +
+| | CONFIG_SEM_PREALLOCHOLDERS | |
++ +-------------------------------+ +
+| | CONFIG_DISABLE_MQUEUE | |
++ +-------------------------------+ +
+| | CONFIG_DISABLE_MQUEUE_SYSV | |
++ +-------------------------------+ +
+| | CONFIG_PREALLOC_MQ_MSGS | |
++ +-------------------------------+ +
+| | CONFIG_PREALLOC_MQ_IRQ_MSGS | |
++ +-------------------------------+ +
+| | CONFIG_MQ_MAXMSGSIZE | |
++-----------------+-------------------------------+------------------+
+
+.. _arch/Kconfig: https://github.com/apache/nuttx/blob/master/arch/Kconfig
+.. _sched/Kconfig: https://github.com/apache/nuttx/blob/master/sched/Kconfig
+.. _mm/Kconfig: https://github.com/apache/nuttx/blob/master/mm/Kconfig
+.. _serial/Kconfig:
https://github.com/apache/nuttx/blob/master/drivers/serial/Kconfig
