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
16static int mx25_cpu_rev = -1;
17
18static 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, compat: "fsl,imx25-iim");
25 iim_base = of_iomap(node: np, index: 0);
26 of_node_put(node: np);
27 BUG_ON(!iim_base);
28 rev = readl(addr: iim_base + MXC_IIMSREV);
29 iounmap(addr: 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
43int 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}
50EXPORT_SYMBOL(mx25_revision);
51

source code of linux/arch/arm/mach-imx/cpu-imx25.c