Mini howto build toolschain and initramfs on Linux

This is about how to update uClibc to 0.9.28 stable release.

http://www.uclibc.org/downloads/uclibc-0.9.28.tar.bz2 (http://www.uclibc.org/downloads/uclibc-0.9.28.tar.bz2)

You should config the lib install dir to a new place.

And change the UCLIBC_PLUGIN for busybox and apps to this new place.

You should turn on "wide char support" in "string and stdio support" for busybox to work.

After installed the new uclibc, make clean and rebuild busybox and apps.

Then update kernel image with initramfs.

The daily snapshot of uClibc is still broken for nios2.

Patch,

--- Rules.mak    2005/12/29 07:20:49    1.1
+++ Rules.mak    2005/12/30 01:43:32
@@ -266,7 +266,9 @@
#  If -msoft-float isn't supported, we want an error anyway.
#  Hmm... might need to revisit this for arm since it has 2 different
#  soft float encodings.
+ifneq ($(strip $(TARGET_ARCH)),nios2)
     CPU_CFLAGS += -msoft-float
+endif
 ifeq ($(strip $(TARGET_ARCH)),arm)
#  No longer needed with current toolchains, but leave it here for now.
#  If anyone is actually still using gcc 2.95 (say), they can uncomment it.
--- libc/sysdeps/linux/nios2/crt0.S    2005/12/29 07:03:01    1.1
+++ libc/sysdeps/linux/nios2/crt0.S    2005/12/30 03:07:54
@@ -6,7 +6,8 @@
  * This file is subject to the terms and conditions of the GNU Lesser
  * General Public License.  See the file COPYING.LIB in the main
  * directory of this archive for more details.
  *
  * Written by Wentao Xu <wentao@microtronix.com>
+ * udpated by hippo  for  uClibc 0.9.28 and newer
  * 
  */
@@ -18,7 +19,8 @@
     .type   __start,@function
     .weak   _init
     .weak   _fini
-    .type   __uClibc_start_main,@function
+    .type   main,@function
+    .type   __uClibc_main,@function
     .type   __h_errno_location, @function
     .type   _stdio_init, @function
     .type   _stdio_term, @function
@@ -36,9 +38,10 @@
     addi gp, gp, %lo(_gp)
 
     /* load argc, argv, envp from stack */
-    ldw r4, 0(sp)
-    ldw r5, 4(sp)
-    ldw r6, 8(sp)
+    movhi r4, %hi(main)
+    ori  r4, r4, %lo(main)    /* main */
+    ldw r5, 0(sp)  /* argc */
+    ldw r6, 4(sp)  /* argv */
     
     /* load the 4th arg */
     movhi r7, %hi(_init)
@@ -48,17 +51,19 @@
     movhi r8, %hi(_fini)
     ori  r8, r8, %lo(_fini)
     stw  r8, 0(sp)
-   
+    stw  r2, 4(sp)  /* rtld_fini */
+    stw  sp, 8(sp)  /* stack_end */
+    
     /* call uClibc_main, shouldn&#39;t return */
# ifdef __PIC__
     /* just pray 16 bit offset is enough */
-    br __uClibc_start_main
+    br __uClibc_main
# else
-    call __uClibc_start_main
+    call __uClibc_main
# endif
 
     /* crash in the event of return */
 __exit:
     movui r2, TRAP_ID_SYSCALL
     movui r3, __NR_exit
-    trap
+    trap

Run,

#fix for autoconf.h
make ARCH_CFLAGS="-I(your kernel build/include)" menuconfig
make ARCH_CFLAGS="-I(your kernel build/include)"
make ARCH_CFLAGS="-I(your kernel build/include)" install

The .config must have,

##  Target Architecture Features and Options# 
KERNEL_SOURCE="your kernel source linux-2.6.x"# #  uClibc development/debugging options# 
CROSS_COMPILER_PREFIX="nios2-elf-"