arch/arm64: Add Revision, Serial, Model to cpuinfo

raspberrypi inclusion
category: feature
bugzilla: 50432

--------------------------------
Signed-off-by: NPhil Elwell <phil@raspberrypi.org>
Signed-off-by: NFang Yafen <yafen@iscas.ac.cn>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

arch/arm64/kernel/cpuinfo.c

@@ -17,6 +17,7 @@
 #include <linux/elf.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
+#include <linux/of_platform.h>
 #include <linux/personality.h>
 #include <linux/preempt.h>
 #include <linux/printk.h>
@@ -137,6 +138,10 @@ static int c_show(struct seq_file *m, void *v)
 {
 	int i, j;
 	bool aarch32 = personality(current->personality) == PER_LINUX32;
+	struct device_node *np;
+	const char *model;
+	const char *serial;
+	u32 revision;
 
 	for_each_online_cpu(i) {
 		struct cpuinfo_arm64 *cpuinfo = &per_cpu(cpu_data, i);
@@ -197,6 +202,26 @@ static int c_show(struct seq_file *m, void *v)
 		seq_printf(m, "CPU revision\t: %d\n\n", MIDR_REVISION(midr));
 	}
 
+	seq_printf(m, "Hardware\t: BCM2835\n");
+
+	np = of_find_node_by_path("/system");
+	if (np) {
+		if (!of_property_read_u32(np, "linux,revision", &revision))
+			seq_printf(m, "Revision\t: %04x\n", revision);
+		of_node_put(np);
+	}
+
+	np = of_find_node_by_path("/");
+	if (np) {
+		if (!of_property_read_string(np, "serial-number",
+					     &serial))
+			seq_printf(m, "Serial\t\t: %s\n", serial);
+		if (!of_property_read_string(np, "model",
+					     &model))
+			seq_printf(m, "Model\t\t: %s\n", model);
+		of_node_put(np);
+	}
+
 	return 0;
 }