1/*
2 * MX31 CPU type detection
3 *
4 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12#include <linux/module.h>
13#include <linux/io.h>
14
15#include "common.h"
16#include "hardware.h"
17#include "iim.h"
18
19static int mx31_cpu_rev = -1;
20
21static struct {
22	u8 srev;
23	const char *name;
24	unsigned int rev;
25} mx31_cpu_type[] = {
26	{ .srev = 0x00, .name = "i.MX31(L)", .rev = IMX_CHIP_REVISION_1_0 },
27	{ .srev = 0x10, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_1 },
28	{ .srev = 0x11, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_1 },
29	{ .srev = 0x12, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_1 },
30	{ .srev = 0x13, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_1 },
31	{ .srev = 0x14, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_2 },
32	{ .srev = 0x15, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_2 },
33	{ .srev = 0x28, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_2_0 },
34	{ .srev = 0x29, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_2_0 },
35};
36
37static int mx31_read_cpu_rev(void)
38{
39	u32 i, srev;
40
41	/* read SREV register from IIM module */
42	srev = __raw_readl(MX31_IO_ADDRESS(MX31_IIM_BASE_ADDR + MXC_IIMSREV));
43	srev &= 0xff;
44
45	for (i = 0; i < ARRAY_SIZE(mx31_cpu_type); i++)
46		if (srev == mx31_cpu_type[i].srev) {
47			imx_print_silicon_rev(mx31_cpu_type[i].name,
48						mx31_cpu_type[i].rev);
49			return mx31_cpu_type[i].rev;
50		}
51
52	imx_print_silicon_rev("i.MX31", IMX_CHIP_REVISION_UNKNOWN);
53	return IMX_CHIP_REVISION_UNKNOWN;
54}
55
56int mx31_revision(void)
57{
58	if (mx31_cpu_rev == -1)
59		mx31_cpu_rev = mx31_read_cpu_rev();
60
61	return mx31_cpu_rev;
62}
63EXPORT_SYMBOL(mx31_revision);
64