| .. 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 confirm 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 following 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. | |
| +------+---------------+--------------------------------------------------------------------+ |
| |
| Porting Case Studies |
| =============================== |
| |
| These porting guides depend on specific kernel versions, as some code structures have changed over time. They will still |
| provide a general idea on how to port. |
| |
| .. toctree:: |
| :glob: |
| :maxdepth: 1 |
| |
| porting-case-studies/* |
