[WIP] Cross-compiler for arm-none-eabi

[Ricardo Wurmus]

Hi Guix,

attached is a patch blob providing the “embedded.scm” module.  I’m using
this cross-compiler semi-successfully to build so-called “patches” for
the Axoloti audio development/prototyping board.

I’m using the cross binutils at a particular git commit; the same
applies to “gcc-arm-none-eabi”, which takes the GCC sources from SVN.
This is done because these revisions are known to work.  Axoloti
upstream uses a binary cross-compiler toolchain release, which is
available here:

    https://launchpad.net/gcc-arm-embedded/4.9/4.9-2015-q2-update

The module also contains “newlib-arm-none-eabi” and
“newlib-nano-arm-none-eabi”, which is used instead of the glibc.

In “gnu/packages/bootstrap.scm” I made a tiny change to keep
“glibc-dynamic-linker” from failing.

Now, I have a problem with this toolchain: it doesn’t seem to work
properly.  While I can build “patches” for Axoloti that are linked with
the pre-compiled firmware from upstream, I cannot seem to create a
working firmware binary (that’s ChibiOS with extensions).  There are no
errors when I build it; it generates an elf file.  But when it is
uploaded to the board the system won’t boot.  I have to flash upstream’s
binary firmware with dfu-util to revive the board.

Generating “patches” on the other hand works fine.  It’s really just
this:

~~~~~~~~~~~
/gnu/store/p787lrv17m25v0cdrdzw66r9b7hk1109-gcc-cross-sans-libc-arm-none-eabi-4.9.3-1.224288/bin/arm-none-eabi-g++
 -nostdlib -fno-exceptions -fno-rtti -mcpu=cortex-m4 -O3 -fomit-frame-pointer 
-falign-functions=16 -mfloat-abi=hard -mfpu=fpv4-sp-d16 
-fsingle-precision-constant -Wunused-parameter -DCORTEX_USE_FPU=TRUE 
-DTHUMB_PRESENT -mno-thumb-interwork -DTHUMB_NO_INTERWORKING -mthumb -DTHUMB 
-std=c++11 -DARM_MATH_CM4 -D__FPU_PRESENT -H 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/CMSIS/Include
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/ports/common/ARMCMx/CMSIS/include
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/ports/common/ARMCMx
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/ports/GCC/ARMCMx
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/ports/GCC/ARMCMx/STM32F4xx
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/kernel/include
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/include
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32F4xx
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32/GPIOv2
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32/I2Cv1
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32/OTGv1
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32/RTCv2
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32/SPIv1
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32/TIMv1
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/os/hal/platforms/STM32/USARTv1
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/boards/ST_STM32F4_DISCOVERY
 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios/ext/fatfs/src
 -I. 
-I/gnu/store/ysyi04kr6y4sbp5s6yyvpy3kl2yhppyh-axoloti-patcher-1.0.6/share/axoloti/chibios
 -Winvalid-pch -MD -MP --include /home/rekado/axoloti/build/xpatch.h -c 
/home/rekado/axoloti/build/xpatch.cpp -o /home/rekado/axoloti/build/xpatch.o 
~~~~~~~~~~~

Since the command that works does not involve the linker as far as I can
tell my guess is that the linker is somehow broken (or that maybe
linking with “newlib” instead “glibc” doesn’t quite work).

I have never before built cross-compilers and I don’t really know what
I’m doing.

If you have any suggestions I’d be glad to hear them!

~~ Ricardo

>From 18b057d628f849dd11de1756068e2bee5986f584 Mon Sep 17 00:00:00 2001
From: Ricardo Wurmus <address@hidden>
Date: Thu, 3 Mar 2016 18:07:30 +0100
Subject: [PATCH 1/2] WIP arm-none-eabi cross-compiler

---
 gnu/packages/bootstrap.scm |   1 +
 gnu/packages/embedded.scm  | 160 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 161 insertions(+)
 create mode 100644 gnu/packages/embedded.scm

diff --git a/gnu/packages/bootstrap.scm b/gnu/packages/bootstrap.scm
index f5bf069..4acbb62 100644
--- a/gnu/packages/bootstrap.scm
+++ b/gnu/packages/bootstrap.scm
@@ -169,6 +169,7 @@ successful, or false to signal an error."
 
         ;; XXX: This one is used bare-bones, without a libc, so add a case
         ;; here just so we can keep going.
+        ((string=? system "arm-eabi") "no-ld.so")
         ((string=? system "xtensa-elf") "no-ld.so")
         ((string=? system "avr") "no-ld.so")
 
diff --git a/gnu/packages/embedded.scm b/gnu/packages/embedded.scm
new file mode 100644
index 0000000..bf6b44d
--- /dev/null
+++ b/gnu/packages/embedded.scm
@@ -0,0 +1,160 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2016 Ricardo Wurmus <address@hidden>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu packages embedded)
+  #:use-module (guix utils)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix svn-download)
+  #:use-module (guix git-download)
+  #:use-module ((guix licenses) #:prefix license:)
+  #:use-module (guix build-system gnu)
+  #:use-module (gnu packages)
+  #:use-module (gnu packages bison)
+  #:use-module (gnu packages cross-base)
+  #:use-module (gnu packages flex)
+  #:use-module (gnu packages perl)
+  #:use-module (gnu packages texinfo))
+
+(define-public xbinutils-arm-none-eabi
+  (let ((parent (cross-binutils "arm-none-eabi"))
+        (commit "136a940ac535e464d2a7a86880ce1f1a5554c484"))
+    (package (inherit parent)
+      (source (origin
+                (method git-fetch)
+                (uri (git-reference
+                      (url "git://sourceware.org/git/binutils-gdb.git")
+                      (commit commit)))
+                (file-name (string-append "xbinutils-arm-none-eabi-"
+                                          (package-version parent) "-"
+                                          (string-take commit 9) "-checkout"))
+                (patches (origin-patches (package-source parent)))
+                (sha256
+                 (base32
+                  "185sfmhbplidvj8n3h1clqqf6c0wqcigzm3phn9sqfy9arsv3mg8"))))
+      (native-inputs
+       `(("texinfo" ,texinfo)
+         ("perl" ,perl)
+         ("bison" ,bison)
+         ("flex" ,flex)
+         ,@(package-native-inputs parent)))
+      (arguments
+       `(,@(substitute-keyword-arguments (package-arguments parent)
+             ((#:configure-flags flags)
+              `(cons "--enable-multilib"
+                     (delete "--disable-multilib" ,flags)))))))))
+
+;; Cannot just use the released GCC sources here, must be from SVN.
+(define-public gcc-arm-none-eabi
+  (let ((xgcc (cross-gcc "arm-none-eabi"
+                         xbinutils-arm-none-eabi))
+        (revision 224288))
+    (package (inherit xgcc)
+      (source
+       (origin
+         (method svn-fetch)
+         (uri (svn-reference
+               (url 
"svn://gcc.gnu.org/svn/gcc/branches/ARM/embedded-4_9-branch/")
+               (revision revision)))
+         (file-name (string-append "gcc-arm-embedded-"
+                                   (package-version xgcc) "-"
+                                   (number->string revision) "-checkout"))
+         (sha256
+          (base32
+           "113r98kygy8rrjfv2pd3z6zlfzbj543pq7xyq8bgh72c608mmsbr"))
+         (patches (origin-patches (package-source xgcc)))))
+      (native-inputs
+       `(("flex" ,flex)
+         ,@(package-native-inputs xgcc)))
+      (arguments
+       `(,@(substitute-keyword-arguments (package-arguments xgcc)
+             ((#:phases phases)
+              `(modify-phases ,phases
+                 (add-after 'unpack 'fix-genmultilib
+                   (lambda _
+                     (substitute* "gcc/genmultilib"
+                       (("#!/bin/sh") (string-append "#!" (which "sh"))))
+                     #t))))
+             ((#:configure-flags flags)
+              `(cons "--with-newlib"
+                     (cons "--enable-multilib"
+                           (delete "--disable-multilib" ,flags))))))))))
+
+(define-public newlib-arm-none-eabi
+  (package
+    (name "newlib")
+    (version "2.2.0")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "ftp://sourceware.org/pub/newlib/newlib-";
+                                  version ".tar.gz"))
+              (sha256
+               (base32
+                "1gimncxzq663l4gp8zd89ynfzhk2q802mcaiyjpr2xbkn1ix5bgq"))))
+    (build-system gnu-build-system)
+    (arguments
+     `(#:out-of-source? #t
+       #:configure-flags '("--target=arm-none-eabi"
+                           "--enable-newlib-io-long-long"
+                           "--enable-newlib-register-fini"
+                           "--disable-newlib-supplied-syscalls"
+                           "--disable-nls")
+       #:phases
+       (modify-phases %standard-phases
+         (add-after 'unpack 'fix-shell-shebangs-please
+           (lambda _
+             (setenv "SHELL" (which "sh"))
+             (setenv "CONFIG_SHELL" (which "sh"))
+             (substitute* '("libgloss/arm/configure"
+                            "libgloss/arm/cpu-init/Makefile.in"
+                            "libgloss/arm/Makefile.in"
+                            "libgloss/libnosys/Makefile.in"
+                            "libgloss/Makefile.in")
+               (("/bin/sh") (which "sh")))
+             #t)))))
+    (native-inputs `(("xbinutils" ,xbinutils-arm-none-eabi)
+                     ("xgcc" ,gcc-arm-none-eabi)
+                     ("texinfo" ,texinfo)))
+    (home-page "http://www.sourceware.org/newlib/";)
+    (synopsis "C library for use on embedded systems")
+    (description
+     "Newlib is a C library intended for use on embedded systems.  It is a
+conglomeration of several library parts, that are easily usable on embedded
+products.")
+    (license (license:non-copyleft
+              "https://www.sourceware.org/newlib/COPYING.NEWLIB";))))
+
+(define-public newlib-nano-arm-none-eabi
+  (package (inherit newlib-arm-none-eabi)
+    (name "newlib-nano")
+    (arguments
+     (substitute-keyword-arguments (package-arguments newlib-arm-none-eabi)
+       ((#:configure-flags flags)
+        ``("--target=arm-none-eabi"
+           "--enable-multilib"
+           "--disable-newlib-supplied-syscalls"
+           "--enable-newlib-reent-small"
+           "--disable-newlib-fvwrite-in-streamio"
+           "--disable-newlib-fseek-optimization"
+           "--disable-newlib-wide-orient"
+           "--enable-newlib-nano-malloc"
+           "--disable-newlib-unbuf-stream-opt"
+           "--enable-lite-exit"
+           "--enable-newlib-global-atexit"
+           "--enable-newlib-nano-formatted-io"
+           "--disable-nls"))))))
-- 
2.6.3