arm/dt: Allow CONFIG_OF on ARM

Add some basic empty infrastructure for DT support on ARM.

v5: - Fix off-by-one error in size calculation of initrd
    - Stop mucking with cmd_line, and load command line from dt into
      boot_command_line instead which matches the behaviour of ATAGS booting
v3: - moved cmd_line export and initrd setup to this patch to make the
      series bisectable.
    - switched to alloc_bootmem_align() for allocation when
      unflattening the device tree.  memblock_alloc() was not the
      right interface.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 7 insertions, 0 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 377a7a595b08..efc7f3c87f1d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1687,6 +1687,13 @@ endmenu
 
 menu "Boot options"
 
+config USE_OF
+        bool "Flattened Device Tree support"
+        select OF
+        select OF_EARLY_FLATTREE
+        help
+          Include support for flattened device tree machine descriptions.
+
 # Compressed boot loader in ROM.  Yes, we really want to ask about
 # TEXT and BSS so we preserve their values in the config files.
 config ZBOOT_ROM_TEXT