[ARM] 4423/1: add ATAGS support

Examines the ATAGS pointer (r2) at boot, and interprets
a nonzero value as a reference to an ATAGS structure. A
suitable ATAGS structure replaces the kernel's command line.

Signed-off-by: Bill Gatliff <bgat@billgatliff.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 650eac1bc0a6..5be2e987b843 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -63,6 +63,8 @@ unsigned int processor_id;
 unsigned int __machine_arch_type;
 EXPORT_SYMBOL(__machine_arch_type);
 
+unsigned int __atags_pointer __initdata;
+
 unsigned int system_rev;
 EXPORT_SYMBOL(system_rev);
 
@@ -780,7 +782,9 @@ void __init setup_arch(char **cmdline_p)
         if (mdesc->soft_reboot)
                 reboot_setup("s");
 
-        if (mdesc->boot_params)
+        if (__atags_pointer)
+                tags = phys_to_virt(__atags_pointer);
+        else if (mdesc->boot_params)
                 tags = phys_to_virt(mdesc->boot_params);
 
         /*