Linux-libre 4.5-gnu

1 files changed, 31 insertions, 1 deletions

diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
index 04a56cc04..bab814d2f 100644
--- a/arch/arm/mach-omap2/board-generic.c
+++ b/arch/arm/mach-omap2/board-generic.c
@@ -16,7 +16,9 @@
 #include <linux/of_platform.h>
 #include <linux/irqdomain.h>
 
+#include <asm/setup.h>
 #include <asm/mach/arch.h>
+#include <asm/system_info.h>
 
 #include "common.h"
 
@@ -76,8 +78,36 @@ static const char *const n900_boards_compat[] __initconst = {
 	NULL,
 };
 
+/* Set system_rev from atags */
+static void __init rx51_set_system_rev(const struct tag *tags)
+{
+	const struct tag *tag;
+
+	if (tags->hdr.tag != ATAG_CORE)
+		return;
+
+	for_each_tag(tag, tags) {
+		if (tag->hdr.tag == ATAG_REVISION) {
+			system_rev = tag->u.revision.rev;
+			break;
+		}
+	}
+}
+
+/* Legacy userspace on Nokia N900 needs ATAGS exported in /proc/atags,
+ * save them while the data is still not overwritten
+ */
+static void __init rx51_reserve(void)
+{
+	const struct tag *tags = (const struct tag *)(PAGE_OFFSET + 0x100);
+
+	save_atags(tags);
+	rx51_set_system_rev(tags);
+	omap_reserve();
+}
+
 DT_MACHINE_START(OMAP3_N900_DT, "Nokia RX-51 board")
-	.reserve	= omap_reserve,
+	.reserve	= rx51_reserve,
 	.map_io		= omap3_map_io,
 	.init_early	= omap3430_init_early,
 	.init_machine	= omap_generic_init,