Add section to provide some documentation for cross-compiling.

[openocd.git] / README

diff --git a/README b/README
index 07aaf9a4967df6f12078686ca032b063ee0c0408..537bb0cbd28857e0f211269646f8650394f87f03 100644 (file)
--- a/README
+++ b/README
@@ -51,10 +51,11 @@ The OpenOCD User's Guide can be produced in two different format:
 The OpenOCD Developer Manual contains information about the internal
 architecture and other details about the code:
 
+  # NB! make sure doxygen is installed, type doxygen --version
   make doxygen
 
   # If HTMLVIEWER is set, this views the HTML Doxygen output.
-  ${HTMLVIEWER} doxyegen/index.html
+  ${HTMLVIEWER} doxygen/index.html
 
 The remaining sections describe how to configure the system such that
 you can build the in-tree documentation.
@@ -117,18 +118,23 @@ Building OpenOCD
 
 The INSTALL file contains generic instructions for running 'configure'
 and compiling the OpenOCD source code.  That file is provided by default
-for all GNU automake packages, and 
+for all GNU automake packages.  If you are not familiar with the GNU
+autotools, then you should read those instructions first.  
 
-if you are not familiar with the GNU autotools, then you should read
-those instructions first.  
-Still, the
-remainder of this document tries to provide complete instructions for
-those looking for a quick-install
+The remainder of this document tries to provide some instructions for
+those looking for a quick-install.
 
 OpenOCD Dependencies
 --------------------
 
-You will need to install the appropriate driver files, if you want to
+Presently, GCC is required to build OpenOCD.  The developers have begun
+to enforce strict code warnings (-Wall, -Werror, -Wextra, and more) and
+use C99-specific features: inline functions, named initializers, mixing
+declarations with code, and other tricks.  While it may be possible to
+use other compilers, they must be somewhat modern and could require
+extending support to conditionally remove GCC-specific extensions.
+
+Also, you need to install the appropriate driver files, if you want to
 build support for a USB or FTDI-based interface:
 
 - ft2232, jlink, rlink, vsllink, usbprog, arm-jtag-ew:
@@ -136,9 +142,14 @@ build support for a USB or FTDI-based interface:
 - ft2232 also requires:
   - libftdi: http://www.intra2net.com/opensource/ftdi/  *OR*
   - ftd2xx: http://www.ftdichip.com/Drivers/D2XX.htm,
-    or the Amontec version (from @uref{http://www.amontec.com}), for
+    or the Amontec version (from http://www.amontec.com), for
     easier support of JTAGkey's vendor and product IDs.
 
+Many Linux distributions provide these packages through their automated
+installation and update mechanisms; however, some Linux versions include
+older versions of libftdi.  In particular, using Ubuntu 8.04 has been
+problematic, but newer versions of Ubuntu do not have this problem.
+
 Compiling OpenOCD
 -----------------
 
@@ -155,6 +166,29 @@ will build OpenOCD and place the final executable in ./src/.  The
 final (optional) step, ``make install'', places all of the files in the
 required location.
 
+Cross-Compiling Options
+-----------------------
+
+To cross-compile, you must specify both --build and --host options to
+the 'configure' script.  For example, you can configure OpenOCD to
+cross-compile on a x86 Linux host to run on Windows (MinGW32), you could
+use the following configuration options:
+
+  ./configure --build=i686-pc-linux-gnu --host=i586-mingw32msvc ... 
+
+Likewise, the following options allow OpenOCD to be cross-compiled for
+an ARM target on the same x86 host:
+
+  ./configure --build=i686-pc-linux-gnu --host=arm-elf ...
+
+Both must be specified to work around bugs in autoconf.
+
+Scripts for producing ARM cross-compilers can be found on the web with a
+little searching.  A script to produce an x86 Linux-hosted MinGW32
+cross-compiler can be downloaded from the following URL:
+
+  http://www.mingw.org/wiki/LinuxCrossMinGW
+
 Configuration Options
 ---------------------
 
@@ -242,11 +276,6 @@ The following additional options may also be useful:
   --disable-wextra        Disable extra compiler warnings
   --disable-werror        Do not treat warnings as errors
 
-  --enable-release        Enable building of an OpenOCD release.  This
-                         option is intended for project maintainers.
-                         It simply omits the svn version string when
-                         the openocd -v is executed (to KISS).
-
   --disable-option-checking
                           Ignore unrecognized --enable and --with options.
   --disable-dependency-tracking  speeds up one-time build
@@ -367,7 +396,7 @@ called "openocd" in the current directory):
 
    svn checkout svn://svn.berlios.de/openocd/trunk openocd
 
-If you prefer GIT based tools, the @command{git-svn} package works too:
+If you prefer GIT based tools, the git-svn package works too:
 
    git svn clone -s svn://svn.berlios.de/openocd
 
@@ -376,7 +405,7 @@ Tips For Building From The Subversion Repository
 
 Building OpenOCD from a repository requires a recent version of the GNU
 autotools (autoconf >= 2.59 and automake >= 1.9).  For building on
-Windows, you have to use Cygwin. Make sure that your @env{PATH}
+Windows, you have to use Cygwin. Make sure that your PATH
 environment variable contains no other locations with Unix utils (like
 UnxUtils) - these can't handle the Cygwin paths, resulting in obscure
 dependency errors.  This was an observation gathered from the logs of