openwrtv3/target/linux/brcm2708/patches-4.4/0013-ARM-bcm2835-Set-Serial-number-and-Revision.patch

From 7ce5cbfba6e930c2178f342a4390972f1efd75ef Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= <noralf@tronnes.org>
Date: Wed, 3 Jun 2015 12:26:13 +0200
Subject: [PATCH 013/232] ARM: bcm2835: Set Serial number and Revision
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The VideoCore bootloader passes in Serial number and
Revision number through Device Tree. Make these available to
userspace through /proc/cpuinfo.

Mainline status:

There is a commit in linux-next that standardize passing the serial
number through Device Tree (string: /serial-number):
ARM: 8355/1: arch: Show the serial number from devicetree in cpuinfo

There was an attempt to do the same with the revision number, but it
didn't get in:
[PATCH v2 1/2] arm: devtree: Set system_rev from DT revision

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
---
 arch/arm/mach-bcm/board_bcm2835.c | 9 +++++++++
 1 file changed, 9 insertions(+)

--- a/arch/arm/mach-bcm/board_bcm2835.c
+++ b/arch/arm/mach-bcm/board_bcm2835.c
@@ -17,12 +17,16 @@
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/clk/bcm2835.h>
+#include <asm/system_info.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
 
 static void __init bcm2835_init(void)
 {
+	struct device_node *np = of_find_node_by_path("/system");
+	u32 val;
+	u64 val64;
 	int ret;
 
 	bcm2835_init_clocks();
@@ -33,6 +37,11 @@ static void __init bcm2835_init(void)
 		pr_err("of_platform_populate failed: %d\n", ret);
 		BUG();
 	}
+
+	if (!of_property_read_u32(np, "linux,revision", &val))
+		system_rev = val;
+	if (!of_property_read_u64(np, "linux,serial", &val64))
+		system_serial_low = val64;
 }
 
 static const char * const bcm2835_compat[] = {