1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * MX25 CPU type detection
4  *
5  * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
6  * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved
7  */
8 #include <linux/module.h>
9 #include <linux/io.h>
10 #include <linux/of.h>
11 #include <linux/of_address.h>
12 
13 #include "iim.h"
14 #include "hardware.h"
15 
16 static int mx25_cpu_rev = -1;
17 
mx25_read_cpu_rev(void)18 static int mx25_read_cpu_rev(void)
19 {
20 	u32 rev;
21 	void __iomem *iim_base;
22 	struct device_node *np;
23 
24 	np = of_find_compatible_node(NULL, NULL, "fsl,imx25-iim");
25 	iim_base = of_iomap(np, 0);
26 	of_node_put(np);
27 	BUG_ON(!iim_base);
28 	rev = readl(iim_base + MXC_IIMSREV);
29 	iounmap(iim_base);
30 
31 	switch (rev) {
32 	case 0x00:
33 		return IMX_CHIP_REVISION_1_0;
34 	case 0x01:
35 		return IMX_CHIP_REVISION_1_1;
36 	case 0x02:
37 		return IMX_CHIP_REVISION_1_2;
38 	default:
39 		return IMX_CHIP_REVISION_UNKNOWN;
40 	}
41 }
42 
mx25_revision(void)43 int mx25_revision(void)
44 {
45 	if (mx25_cpu_rev == -1)
46 		mx25_cpu_rev = mx25_read_cpu_rev();
47 
48 	return mx25_cpu_rev;
49 }
50 EXPORT_SYMBOL(mx25_revision);
51