xref: /openbmc/linux/arch/arm/mach-imx/cpu-imx25.c (revision 275876e2)
1 /*
2  * MX25 CPU type detection
3  *
4  * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
5  * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12 #include <linux/module.h>
13 #include <linux/io.h>
14 
15 #include "iim.h"
16 #include "hardware.h"
17 
18 static int mx25_cpu_rev = -1;
19 
20 static int mx25_read_cpu_rev(void)
21 {
22 	u32 rev;
23 
24 	rev = __raw_readl(MX25_IO_ADDRESS(MX25_IIM_BASE_ADDR + MXC_IIMSREV));
25 	switch (rev) {
26 	case 0x00:
27 		return IMX_CHIP_REVISION_1_0;
28 	case 0x01:
29 		return IMX_CHIP_REVISION_1_1;
30 	default:
31 		return IMX_CHIP_REVISION_UNKNOWN;
32 	}
33 }
34 
35 int mx25_revision(void)
36 {
37 	if (mx25_cpu_rev == -1)
38 		mx25_cpu_rev = mx25_read_cpu_rev();
39 
40 	return mx25_cpu_rev;
41 }
42 EXPORT_SYMBOL(mx25_revision);
43