xref: /OK3568_Linux_fs/kernel/arch/arm/mach-s3c/cpu.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun //
3*4882a593Smuzhiyun // Copyright (c) 2009-2011 Samsung Electronics Co., Ltd.
4*4882a593Smuzhiyun //		http://www.samsung.com
5*4882a593Smuzhiyun //
6*4882a593Smuzhiyun // Samsung CPU Support
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #include <linux/module.h>
9*4882a593Smuzhiyun #include <linux/kernel.h>
10*4882a593Smuzhiyun #include <linux/init.h>
11*4882a593Smuzhiyun #include <linux/io.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #include <mach/map-base.h>
14*4882a593Smuzhiyun #include "cpu.h"
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun unsigned long samsung_cpu_id;
17*4882a593Smuzhiyun 
s3c64xx_init_cpu(void)18*4882a593Smuzhiyun void __init s3c64xx_init_cpu(void)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun 	samsung_cpu_id = readl_relaxed(S3C_VA_SYS + 0x118);
21*4882a593Smuzhiyun 	if (!samsung_cpu_id) {
22*4882a593Smuzhiyun 		/*
23*4882a593Smuzhiyun 		 * S3C6400 has the ID register in a different place,
24*4882a593Smuzhiyun 		 * and needs a write before it can be read.
25*4882a593Smuzhiyun 		 */
26*4882a593Smuzhiyun 		writel_relaxed(0x0, S3C_VA_SYS + 0xA1C);
27*4882a593Smuzhiyun 		samsung_cpu_id = readl_relaxed(S3C_VA_SYS + 0xA1C);
28*4882a593Smuzhiyun 	}
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun 	pr_info("Samsung CPU ID: 0x%08lx\n", samsung_cpu_id);
31*4882a593Smuzhiyun }
32