=====
Misoc
=====

This README applies to a port to NuttX running on a Qemu LM32 system.  You can
find the Qemu setup at https://bitbucket.org/key2/qemu

This initial release supports two UARTs, but does not have a system timer or
other peripherals. More to come.

Buildroot Toolchain
===================

A GNU GCC-based toolchain is assumed. The ``PATH`` environment variable should
be modified to point to the correct path to the LM32 GCC toolchain (if different
from the default in your ``PATH`` variable).

If you have no LM32 toolchain, one can be cloned from the NuttX Bitbucket GIT
repository (https://bitbucket.org/nuttx/buildroot). This GNU toolchain builds
and executes in the Linux or Cygwin environment.

1. You must have already configured NuttX in ``<some-dir>/nuttx``.

.. code:: console

   $ tools/configure.sh misoc:<sub-dir>
   $ make oldconfig context

2. Clone the latest buildroot package into <some-dir>/buildroot

.. code:: console

   $ git clone git@bitbucket.org:nuttx/buildroot.git <some-dir>/buildroot

or

.. code:: console

   $ git clone https://patacongo@bitbucket.org/nuttx/buildroot.git <some-dir>/buildroot

3. 

.. code:: console

   $ cd <some-dir>/buildroot
   $ cp lm32-elf-defconfig-6.1.0 .config
   $ make oldconfig
   $ make

4. By default, the tools will be at the absolute path: ``<some-dir>/buildroot/build_lm32/staging_dir/bin``

   Or the NuttX relative path: ``../buildroot/build_lm32/staging_dir/bin``

   Make sure that the PATH variable includes the path to the newly built binaries.

See the file ``boards/README.txt`` in the buildroot source tree.  That has more
detailed PLUS some special instructions that you will need to follow if you are
building a LM32 toolchain for Cygwin under Windows.  Also included in that
README file is a FAQ of frequent build issues that their work-arounds.

In order to use the buildroot toolchain, you also must set the following
in your ``.config`` file: ``CONFIG_LM3S_TOOLCHAIN_BUILDROOT=y``

``boards/misoc/lm32/misoc/include/generated``
=============================================

In order to build this configuration, you must provide the
``boards/misoc/lm32/misoc/include/generated`` directory.  It contains the generated
Misoc files and may be a symbolic link.  The base configuration will NOT build
without this directory!

There is a sample generated directory at
``boards/misoc/include/generated-sample``. If you want to do a test build
without generating the architecture, then you can simply link this sample
directory like:

.. code:: console

   $ ln -s boards/misoc/lm32/misoc/include/generated-sample boards/misoc/lm32/misoc/include/generated

That should permit a test build.