[PATCH 0/6] Integrator devicetree support

On Thu, Aug 16, 2012 at 3:44 PM, Arnd Bergmann [off-list ref] wrote:

On Thursday 16 August 2012, Linus Walleij wrote:

quoted

This patch set moves all the non-DT platform code into
#ifndef CONFIG_OF sections for clarity. The plan is to
delete them after deprecation.

I'm fine with your playing around with this in any way you
like, but I think in general we should have a new CONFIG_ATAG
symbol, so you can build a kernel that supports booting
both with and without DT for the same platform, depending
on what the boot loader supports.

Then you can enclose all the non-DT sections in #ifdef
CONFIG_ATAG and we can remove them at some later stage.

Since we already have CONFIG_USE_OF I think
CONFIG_USE_ATAGS is more apropriate, but I get the
idea. So it begins like this:

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index e91c7cd..0764ef7 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig

@@ -1907,6 +1907,12 @@ endmenu

 menu "Boot options"

+config USE_ATAGS
+       bool "ATAGS support"
+       default y
+       help
+         Include support for ATAGS-based machine descriptions.
+
 config USE_OF
        bool "Flattened Device Tree support"
        select OF

@@ -2110,6 +2116,7 @@ config KEXEC

 config ATAGS_PROC
        bool "Export atags in procfs"
+       depends on USE_ATAGS
        depends on KEXEC
        default y
        help

But then we hit #ifdeffing and compiling out a lot of dangerous stuff
in arch/arm/kernel and then I get the creeps. I can try, but I think
this is typical Nico territory for example...

Yours,
Linus Walleij