Add build instructions

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@1481 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 87 insertions, 0 deletions

diff --git a/misc/buildroot/configs/README.txt b/misc/buildroot/configs/README.txt
index c27affd7f..43ac6ce74 100644
--- a/misc/buildroot/configs/README.txt
+++ b/misc/buildroot/configs/README.txt
@@ -1,3 +1,6 @@
+AVAILABLE CONFIGURATIONS
+^^^^^^^^^^^^^^^^^^^^^^^^
+
 arm-defconfig
 	Builds an ARM toolchain using gcc 3.4.5
 
@@ -18,3 +21,87 @@ m68k-config
 
 sh-defconfig
 	Builds an SH-1/2 toolchain using gcc 3.4.5
+
+GENERAL BUILD STEPS
+^^^^^^^^^^^^^^^^^^^
+
+1. CD to the correct directory.
+
+   Change to the directory just above the NuttX installation.  If <nuttx-dir> is
+   where NuttX is installed, then cd to <nuttx-dir>/..
+
+2. Get and Install the buildroot Module
+
+   a. Using a release tarball:
+
+     cd <nuttx-dir>/..
+     Download the appropriate buildroot package.
+     unpack the buildroot package
+     rename the directory to buildroot
+
+   b. Using CVS
+   
+     Check out the misc/buildroot module. CVS checkout instructions:
+
+        cvs -d:pserver:anonymous@nuttx.cvs.sourceforge.net:/cvsroot/nuttx login
+        cvs -z3 -d:pserver:anonymous@nuttx.cvs.sourceforge.net:/cvsroot/nuttx co -P misc/buildroot
+
+     Move the buildroot Source Tree and create the archive directory
+
+        mv misc/buildroot .
+
+   Make the archive directory:
+  
+     mkdir archive
+
+   The <nuttx-dir>/../buildroot is where the toolchain is built;
+   The <nuttx-dir>/../archive directory is where toolchain sources will be downloaded.
+
+3. Make sure that NuttX is configured
+
+     cd <nuttx-dir>/tools
+     ./configure.sh <nuttx-configuration>
+     
+4. Configure and Make the buildroot
+
+     cd buildroot
+     cp configs/<config-file> .config
+     make oldconfig
+     make
+
+   This will download the large source packages for the toolchain and build the toolchain.
+   The resulting binaries will be under buildroot/build_<arch>.  There will also be a
+   large build directory called something like toolchain_build_<arch>; this directory
+   can be removed once the build completes successfully.
+
+   Where <config-file> is one of the configuration files listed above and <arch> is an
+   archtecture name.  Examples: build_m32c, build_arm_nofpu, etc.
+
+Cygwin GCC BUILD NOTES
+^^^^^^^^^^^^^^^^^^^^^^
+   On Cygwin, the buildroot 'make' command will fail with an error like:
+
+   "...
+      build/genchecksum cc1-dummy > cc1-checksum.c
+      opening cc1-dummy: No such file or directory
+   ..."
+
+   This is caused because on Cygwin, host executables will be generated with the extension .exe
+   and, apparently, the make variable "exeext" is set incorrectly.  A work around after the
+   above occurs is:
+
+      cd toolchain_build_<arch>/gcc-4.2.4-initial/gcc	# Go to the directory where error occurred
+      mv cc1-dummy.exe cc1-dummy			# Rename the executable without .exe
+      rm cc1-checksum.c					# Get rid of the bad generated file
+
+   Then resume the buildroot make:
+
+      cd -						# Back to the buildroot make directory
+      make						# Restart the build
+
+   GCC is built twice.  First a initial, "bootstap" GCC is produced in
+   toolchain_build_<arch>/gcc-4.2.4-initial, then the final GCC is produced in
+   toolchain_build_<arch>/gcc-4.2.4-final.  The above error will occur twice:  Once for
+   the intial GCC build (see above) and once for the final GCC build. For the final GCC
+   build, the workaround is the same except that the directory will be
+   toolchain_build_<arch>/gcc-4.2.4-final/gcc.