Add support for a saving build objects in a separate directory.

Modifications are based on the linux kernel approach and
support two use cases:

  1) Add O= to the make command line
  'make O=/tmp/build all'

  2) Set environement variable BUILD_DIR to point to the desired location
  'export BUILD_DIR=/tmp/build'
  'make'

The second approach can also be used with a MAKEALL script
'export BUILD_DIR=/tmp/build'
'./MAKEALL'

Command line 'O=' setting overrides BUILD_DIR environent variable.

When none of the above methods is used the local build is performed and
the object files are placed in the source directory.

1 files changed, 35 insertions, 6 deletions

diff --git a/drivers/nand/Makefile b/drivers/nand/Makefile
index 96f67dfca88..d7076586121 100644
--- a/drivers/nand/Makefile
+++ b/drivers/nand/Makefile
@@ -1,16 +1,45 @@
+#
+# (C) Copyright 2006
+# Wolfgang Denk, DENX Software Engineering, wd@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
+#
+
 include $(TOPDIR)/config.mk
 
-LIB := libnand.a
+LIB 	:= $(obj)libnand.a
+
+COBJS 	:= nand.o nand_base.o nand_ids.o nand_ecc.o nand_bbt.o
+
+SRCS 	:= $(COBJS:.o=.c)
+OBJS 	:= $(addprefix $(obj),$(COBJS))
 
-OBJS := nand.o nand_base.o nand_ids.o nand_ecc.o nand_bbt.o
 all:	$(LIB)
 
-$(LIB):	$(OBJS)
+$(LIB):	$(obj).depend $(OBJS)
 	$(AR) crv $@ $(OBJS)
 
 #########################################################################
 
-.depend:	Makefile $(OBJS:.o=.c)
-		$(CC) -M $(CFLAGS) $(OBJS:.o=.c) > $@
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
 
-sinclude .depend
+sinclude $(obj).depend
+
+#########################################################################