sh: kexec: Add PHYSICAL_START

Add PHYSICAL_START kernel configuration parameter to set the address at
which the kernel should be loaded.

It has been observed on an sh7757lcr that simply modifying MEMORY_START
does not achieve this goal for 32bit sh. This is due to MEMORY_OFFSET in
arch/sh/kernel/vmlinux.lds.S bot being based on MEMORY_START on such
systems.

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/boot/Makefile b/arch/sh/boot/Makefile
index ba515d8..e4ea31a 100644
--- a/arch/sh/boot/Makefile
+++ b/arch/sh/boot/Makefile
@@ -19,6 +19,7 @@
 CONFIG_BOOT_LINK_OFFSET	?= 0x00800000
 CONFIG_ZERO_PAGE_OFFSET	?= 0x00001000
 CONFIG_ENTRY_OFFSET	?= 0x00001000
+CONFIG_PHYSICAL_START	?= $(CONFIG_MEMORY_START)
 
 suffix-y := bin
 suffix-$(CONFIG_KERNEL_GZIP)	:= gz
@@ -48,7 +49,7 @@
 	$(Q)$(MAKE) $(build)=$(obj)/romimage $@
 
 KERNEL_MEMORY	:= $(shell /bin/bash -c 'printf "0x%08x" \
-		     $$[$(CONFIG_MEMORY_START) & 0x1fffffff]')
+		     $$[$(CONFIG_PHYSICAL_START) & 0x1fffffff]')
 
 KERNEL_LOAD	:= $(shell /bin/bash -c 'printf "0x%08x" \
 		     $$[$(CONFIG_PAGE_OFFSET)  + \
@@ -114,4 +115,5 @@
 	@echo '  Image $@ is ready'
 
 export CONFIG_PAGE_OFFSET CONFIG_MEMORY_START CONFIG_BOOT_LINK_OFFSET \
-       CONFIG_ZERO_PAGE_OFFSET CONFIG_ENTRY_OFFSET KERNEL_MEMORY suffix-y
+       CONFIG_PHYSICAL_START CONFIG_ZERO_PAGE_OFFSET CONFIG_ENTRY_OFFSET \
+       KERNEL_MEMORY suffix-y