ppc4xx: Add Canyonlands NAND booting support

460EX doesn't support a fixed bootstrap option to boot from 512 byte page
NAND devices. The only bootstrap option for NAND booting is option F for
2k page devices. So to boot from a 512 bype page device, the I2C bootstrap
EEPROM needs to be programmed accordingly.

This patch adds basic NAND booting support for the AMCC Canyonlands aval
board and also adds support to the "bootstrap" command, to enable NAND
booting I2C setting.

Tested with 512 byte page NAND device (32MByte) on Canyonlands.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/board/amcc/canyonlands/u-boot-nand.lds b/board/amcc/canyonlands/u-boot-nand.lds
new file mode 100644
index 0000000..12a5dcf
--- /dev/null
+++ b/board/amcc/canyonlands/u-boot-nand.lds
@@ -0,0 +1,137 @@
+/*
+ * (C) Copyright 2008
+ * Stefan Roese, DENX Software Engineering, sr@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program 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 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+OUTPUT_ARCH(powerpc)
+SEARCH_DIR(/lib); SEARCH_DIR(/usr/lib); SEARCH_DIR(/usr/local/lib); SEARCH_DIR(/usr/local/powerpc-any-elf/lib);
+SECTIONS
+{
+  /* Read-only sections, merged into text segment: */
+  . = + SIZEOF_HEADERS;
+  .interp : { *(.interp) }
+  .hash          : { *(.hash)		}
+  .dynsym        : { *(.dynsym)		}
+  .dynstr        : { *(.dynstr)		}
+  .rel.text      : { *(.rel.text)		}
+  .rela.text     : { *(.rela.text) 	}
+  .rel.data      : { *(.rel.data)		}
+  .rela.data     : { *(.rela.data) 	}
+  .rel.rodata    : { *(.rel.rodata) 	}
+  .rela.rodata   : { *(.rela.rodata) 	}
+  .rel.got       : { *(.rel.got)		}
+  .rela.got      : { *(.rela.got)		}
+  .rel.ctors     : { *(.rel.ctors)	}
+  .rela.ctors    : { *(.rela.ctors)	}
+  .rel.dtors     : { *(.rel.dtors)	}
+  .rela.dtors    : { *(.rela.dtors)	}
+  .rel.bss       : { *(.rel.bss)		}
+  .rela.bss      : { *(.rela.bss)		}
+  .rel.plt       : { *(.rel.plt)		}
+  .rela.plt      : { *(.rela.plt)		}
+  .init          : { *(.init)	}
+  .plt : { *(.plt) }
+  .text      :
+  {
+    /* WARNING - the following is hand-optimized to fit within	*/
+    /* the sector layout of our flash chips!	XXX FIXME XXX	*/
+
+    cpu/ppc4xx/start.o	(.text)
+
+    /* Align to next NAND block */
+    . = ALIGN(0x4000);
+    common/environment.o  (.ppcenv)
+    /* Keep some space here for redundant env and potential bad env blocks */
+    . = ALIGN(0x10000);
+
+    *(.text)
+    *(.fixup)
+    *(.got1)
+  }
+  _etext = .;
+  PROVIDE (etext = .);
+  .rodata    :
+  {
+    *(.rodata)
+    *(.rodata1)
+    *(.rodata.str1.4)
+  }
+  .fini      : { *(.fini)    } =0
+  .ctors     : { *(.ctors)   }
+  .dtors     : { *(.dtors)   }
+
+  /* Read-write section, merged into data segment: */
+  . = (. + 0x00FF) & 0xFFFFFF00;
+  _erotext = .;
+  PROVIDE (erotext = .);
+  .reloc   :
+  {
+    *(.got)
+    _GOT2_TABLE_ = .;
+    *(.got2)
+    _FIXUP_TABLE_ = .;
+    *(.fixup)
+  }
+  __got2_entries = (_FIXUP_TABLE_ - _GOT2_TABLE_) >>2;
+  __fixup_entries = (. - _FIXUP_TABLE_)>>2;
+
+  .data    :
+  {
+    *(.data)
+    *(.data1)
+    *(.sdata)
+    *(.sdata2)
+    *(.dynamic)
+    CONSTRUCTORS
+  }
+  _edata  =  .;
+  PROVIDE (edata = .);
+
+  . = .;
+  __u_boot_cmd_start = .;
+  .u_boot_cmd : { *(.u_boot_cmd) }
+  __u_boot_cmd_end = .;
+
+
+  . = .;
+  __start___ex_table = .;
+  __ex_table : { *(__ex_table) }
+  __stop___ex_table = .;
+
+  . = ALIGN(256);
+  __init_begin = .;
+  .text.init : { *(.text.init) }
+  .data.init : { *(.data.init) }
+  . = ALIGN(256);
+  __init_end = .;
+
+  __bss_start = .;
+  .bss (NOLOAD)       :
+  {
+   *(.sbss) *(.scommon)
+   *(.dynbss)
+   *(.bss)
+   *(COMMON)
+  }
+
+  _end = . ;
+  PROVIDE (end = .);
+}