added doc/CROSSBUILD - some guidelines

diff --git a/doc/CHANGELOG b/doc/CHANGELOG
index 43028d6..f3b1504 100644 (file)
--- a/doc/CHANGELOG
+++ b/doc/CHANGELOG
@@ -1,5 +1,6 @@
 *) 2004-07-25
 
+- added CROSSBUILD file - just some guidelines for hacking it the hdw way
 - fixed unrealircd package
 - do not build linux mandocs
 - removed unneeded libmustux patch

diff --git a/doc/CROSSBUILD b/doc/CROSSBUILD
new file mode 100644 (file)
index 0000000..0902dee
--- /dev/null
+++ b/doc/CROSSBUILD
@@ -0,0 +1,59 @@
+# hdw - linux CROSS-BUILD howto
+
+with the toolchain concept introduced in version 0.3 of hdw-linux,
+crosscompiling a minimal linux system - which will be used to continue with
+native builds on the foreign architecture hardware - or even building complete
+distributions for slow/embedded hardware should be possible.
+
+here are some guidelines for people developing for aliens.
+
+1) 'straight forward' crossbuilds
+
+  - in Config file set:
+   o hdw_arch          to the alien target architecture
+   o hdw_arch_opt      and the supported cpu optimization
+   o hdw_crossbuild    to "1", so the scripts know about it
+
+  - hack ./scipts/Config file to fix/improve/support your alien architecture
+
+  - add conditional actions to the toolchain and early base packages
+
+  - for architecture specific patches:
+   o use -u option of diff
+   o create patches being applied in the package directory via p1
+   o put these patches to config directory with ending .patch.${hdw_arch}
+
+  - most important: submit your changes!
+
+2) 'tricky' crossbuilds (WTF? - yes, i just dont know any better word ... )
+
+   what are tricky crossbuilds? as i am not able to explain that, i will
+   just give you 2 examples:
+
+   1)
+       host system: sparc64 running 64bit kernel with 32bit userland
+       target system: sparc64 (including 64bit userland)
+
+   2)
+       host system: ia32 i686
+       target system: ia32 i586
+
+   to get around some troubles here diffrent things were implemented:
+
+       o misc/crossbuild/fake_utsname/ - a kernel module to fake the
+         uname output
+       o hdw_real_build - a config parameter that will cause the
+         --build configure flag to the real host system compilers
+
+as you see, crossbuilds are still devel. feel free to hack the scripts, ask
+questions or even kill me for that braindead implementations.
+
+interesting files:
+Config
+scripts/Config
+scripts/optimize
+packages/toolchain/*
+misc/crossbuild/fake_utsname/*
+
+have fun, hackbard.
+