3 files changed, 33 insertions, 9 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index c5f9ae5dbd1a..5c7302e208ce 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1891,12 +1891,6 @@ config CC_STACKPROTECTOR
           neutralized via a kernel panic.
           This feature requires gcc version 4.2 or above.
 
-config DEPRECATED_PARAM_STRUCT
-        bool "Provide old way to pass kernel parameters"
-        help
-          This was deprecated in 2001 and announced to live on for 5 years.
-          Some old boot loaders still use this way.
-
 endmenu
 
 menu "Boot options"
@@ -1909,6 +1903,23 @@ config USE_OF
         help
           Include support for flattened device tree machine descriptions.
 
+config ATAGS
+        bool "Support for the traditional ATAGS boot data passing" if USE_OF
+        default y
+        help
+          This is the traditional way of passing data to the kernel at boot
+          time. If you are solely relying on the flattened device tree (or
+          the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
+          to remove ATAGS support from your kernel binary.  If unsure,
+          leave this to y.
+
+config DEPRECATED_PARAM_STRUCT
+        bool "Provide old way to pass kernel parameters"
+        depends on ATAGS
+        help
+          This was deprecated in 2001 and announced to live on for 5 years.
+          Some old boot loaders still use this way.
+
 # 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
@@ -2035,6 +2046,7 @@ config CMDLINE
 choice
         prompt "Kernel command line type" if CMDLINE != ""
         default CMDLINE_FROM_BOOTLOADER
+        depends on ATAGS
 
 config CMDLINE_FROM_BOOTLOADER
         bool "Use bootloader kernel arguments if available"
@@ -2104,7 +2116,7 @@ config KEXEC
 
 config ATAGS_PROC
         bool "Export atags in procfs"
-        depends on KEXEC
+        depends on ATAGS && KEXEC
         default y
         help
           Should the atags used to boot the kernel be exported in an "atags"
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 086c9d3bc360..79e346a5d78b 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -15,10 +15,12 @@ CFLAGS_REMOVE_return_address.o = -pg
 
 # Object file lists.
 
-obj-y           := atags_parse.o elf.o entry-armv.o entry-common.o irq.o opcodes.o \
+obj-y           := elf.o entry-armv.o entry-common.o irq.o opcodes.o \
                    process.o ptrace.o return_address.o sched_clock.o \
                    setup.o signal.o stacktrace.o sys_arm.o time.o traps.o
 
+obj-$(CONFIG_ATAGS)             += atags_parse.o
+obj-$(CONFIG_ATAGS_PROC)        += atags_proc.o
 obj-$(CONFIG_DEPRECATED_PARAM_STRUCT) += atags_compat.o
 
 obj-$(CONFIG_LEDS)              += leds.o
@@ -52,7 +54,6 @@ test-kprobes-objs		+= kprobes-test-thumb.o
 else
 test-kprobes-objs               += kprobes-test-arm.o
 endif
-obj-$(CONFIG_ATAGS_PROC)        += atags_proc.o
 obj-$(CONFIG_OABI_COMPAT)       += sys_oabi-compat.o
 obj-$(CONFIG_ARM_THUMBEE)       += thumbee.o
 obj-$(CONFIG_KGDB)              += kgdb.o
diff --git a/arch/arm/kernel/atags.h b/arch/arm/kernel/atags.h
index a888fdd381b5..9edc9692332d 100644
--- a/arch/arm/kernel/atags.h
+++ b/arch/arm/kernel/atags.h
@@ -5,4 +5,15 @@ static inline void save_atags(struct tag *tags) { }
 #endif
 
 void convert_to_tag_list(struct tag *tags);
+
+#ifdef CONFIG_ATAGS
 struct machine_desc *setup_machine_tags(phys_addr_t __atags_pointer, unsigned int machine_nr);
+#else
+static inline struct machine_desc *
+setup_machine_tags(phys_addr_t __atags_pointer, unsigned int machine_nr)
+{
+        early_print("no ATAGS support: can't continue\n");
+        while (true);
+        unreachable();
+}
+#endif