MIPS: Refactor load/entry address calculations

The vmlinux load address and entry address is calculated in multiple
places:
 - arch/mips/Makefile defines load-y from CONFIG_PHYSICAL_START (or
   defined by the platform) and passes it to
   arch/mips/boot/compressed/Makefile.
 - arch/mips/boot/compressed/Makefile calculates kernel entry using nm.
 - arch/mips/lasat/image/Makefile calculates both load and entry address
   using nm.

Lets combine these in the main Makefile and then pass them as Make
parameters to each of the three boot image Makefiles (in boot/,
boot/compressed, lasat/image/). The boot/ Makefile doesn't currently use
them, but will soon need to for U-Boot image targets.

The existing load-y definition is used in preference to calculating the
load address using nm.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5794/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index 6e1ab33..91d5baa 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -194,6 +194,8 @@
 ifdef CONFIG_PHYSICAL_START
 load-y					= $(CONFIG_PHYSICAL_START)
 endif
+entry-y				= 0x$(shell $(NM) vmlinux 2>/dev/null \
+					| grep "\bkernel_entry\b" | cut -f1 -d \ )
 
 cflags-y			+= -I$(srctree)/arch/mips/include/asm/mach-generic
 drivers-$(CONFIG_PCI)		+= arch/mips/pci/
@@ -225,6 +227,9 @@
 KBUILD_CPPFLAGS += -DVMLINUX_LOAD_ADDRESS=$(load-y)
 KBUILD_CPPFLAGS += -DDATAOFFSET=$(if $(dataoffset-y),$(dataoffset-y),0)
 
+bootvars-y	= VMLINUX_LOAD_ADDRESS=$(load-y) \
+		  VMLINUX_ENTRY_ADDRESS=$(entry-y)
+
 LDFLAGS			+= -m $(ld-emul)
 
 ifdef CONFIG_CC_STACKPROTECTOR
@@ -267,7 +272,8 @@
 
 ifdef CONFIG_LASAT
 rom.bin rom.sw: vmlinux
-	$(Q)$(MAKE) $(build)=arch/mips/lasat/image $@
+	$(Q)$(MAKE) $(build)=arch/mips/lasat/image \
+		$(bootvars-y) $@
 endif
 
 #
@@ -292,12 +298,13 @@
 
 # boot
 $(boot-y): $(vmlinux-32) FORCE
-	$(Q)$(MAKE) $(build)=arch/mips/boot VMLINUX=$(vmlinux-32) arch/mips/boot/$@
+	$(Q)$(MAKE) $(build)=arch/mips/boot VMLINUX=$(vmlinux-32) \
+		$(bootvars-y) arch/mips/boot/$@
 
 # boot/compressed
 $(bootz-y): $(vmlinux-32) FORCE
 	$(Q)$(MAKE) $(build)=arch/mips/boot/compressed \
-	   VMLINUX_LOAD_ADDRESS=$(load-y) 32bit-bfd=$(32bit-bfd) $@
+		$(bootvars-y) 32bit-bfd=$(32bit-bfd) $@
 
 
 CLEAN_FILES += vmlinux.32 vmlinux.64
diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
index bb1dbf4..0048c08 100644
--- a/arch/mips/boot/compressed/Makefile
+++ b/arch/mips/boot/compressed/Makefile
@@ -25,7 +25,7 @@
 
 KBUILD_AFLAGS := $(LINUXINCLUDE) $(KBUILD_AFLAGS) -D__ASSEMBLY__ \
 	-DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE) \
-	-DKERNEL_ENTRY=0x$(shell $(NM) $(objtree)/$(KBUILD_IMAGE) 2>/dev/null | grep " kernel_entry" | cut -f1 -d \ )
+	-DKERNEL_ENTRY=$(VMLINUX_ENTRY_ADDRESS)
 
 targets := head.o decompress.o dbg.o uart-16550.o uart-alchemy.o
 
diff --git a/arch/mips/lasat/image/Makefile b/arch/mips/lasat/image/Makefile
index dfb509d..fd32075 100644
--- a/arch/mips/lasat/image/Makefile
+++ b/arch/mips/lasat/image/Makefile
@@ -13,13 +13,11 @@
 MKLASATIMG = mklasatimg
 MKLASATIMG_ARCH = mq2,mqpro,sp100,sp200
 KERNEL_IMAGE = vmlinux
-KERNEL_START = $(shell $(NM) $(KERNEL_IMAGE) | grep " _text" | cut -f1 -d\ )
-KERNEL_ENTRY = $(shell $(NM) $(KERNEL_IMAGE) | grep kernel_entry | cut -f1 -d\ )
 
 LDSCRIPT= -L$(srctree)/$(src) -Tromscript.normal
 
-HEAD_DEFINES := -D_kernel_start=0x$(KERNEL_START) \
-		-D_kernel_entry=0x$(KERNEL_ENTRY) \
+HEAD_DEFINES := -D_kernel_start=$(VMLINUX_LOAD_ADDRESS) \
+		-D_kernel_entry=$(VMLINUX_ENTRY_ADDRESS) \
 		-D VERSION="\"$(Version)\"" \
 		-D TIMESTAMP=$(shell date +%s)