summaryrefslogtreecommitdiff
path: root/arch/arm/mach-mvebu/mvebu-soc-id.c
blob: f3d4cf53f7466ba6c44f5ef1d91484e3ce8f62e6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
/*
 * ID and revision information for mvebu SoCs
 *
 * Copyright (C) 2014 Marvell
 *
 * Gregory CLEMENT <gregory.clement@free-electrons.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 *
 * All the mvebu SoCs have information related to their variant and
 * revision that can be read from the PCI control register. This is
 * done before the PCI initialization to avoid any conflict. Once the
 * ID and revision are retrieved, the mapping is freed.
 */

#define pr_fmt(fmt) "mvebu-soc-id: " fmt

#include <linux/clk.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include "mvebu-soc-id.h"

#define PCIE_DEV_ID_OFF		0x0
#define PCIE_DEV_REV_OFF	0x8

#define SOC_ID_MASK	    0xFFFF0000
#define SOC_REV_MASK	    0xFF

static u32 soc_dev_id;
static u32 soc_rev;
static bool is_id_valid;

static const struct of_device_id mvebu_pcie_of_match_table[] = {
	{ .compatible = "marvell,armada-xp-pcie", },
	{ .compatible = "marvell,armada-370-pcie", },
	{ .compatible = "marvell,kirkwood-pcie" },
	{},
};

int mvebu_get_soc_id(u32 *dev, u32 *rev)
{
	if (is_id_valid) {
		*dev = soc_dev_id;
		*rev = soc_rev;
		return 0;
	} else
		return -1;
}

static int __init mvebu_soc_id_init(void)
{
	struct device_node *np;
	int ret = 0;
	void __iomem *pci_base;
	struct clk *clk;
	struct device_node *child;

	np = of_find_matching_node(NULL, mvebu_pcie_of_match_table);
	if (!np)
		return ret;

	/*
	 * ID and revision are available from any port, so we
	 * just pick the first one
	 */
	child = of_get_next_child(np, NULL);
	if (child == NULL) {
		pr_err("cannot get pci node\n");
		ret = -ENOMEM;
		goto clk_err;
	}

	clk = of_clk_get_by_name(child, NULL);
	if (IS_ERR(clk)) {
		pr_err("cannot get clock\n");
		ret = -ENOMEM;
		goto clk_err;
	}

	ret = clk_prepare_enable(clk);
	if (ret) {
		pr_err("cannot enable clock\n");
		goto clk_err;
	}

	pci_base = of_iomap(child, 0);
	if (pci_base == NULL) {
		pr_err("cannot map registers\n");
		ret = -ENOMEM;
		goto res_ioremap;
	}

	/* SoC ID */
	soc_dev_id = readl(pci_base + PCIE_DEV_ID_OFF) >> 16;

	/* SoC revision */
	soc_rev = readl(pci_base + PCIE_DEV_REV_OFF) & SOC_REV_MASK;

	is_id_valid = true;

	pr_info("MVEBU SoC ID=0x%X, Rev=0x%X\n", soc_dev_id, soc_rev);

	iounmap(pci_base);

res_ioremap:
	clk_disable_unprepare(clk);

clk_err:
	of_node_put(child);
	of_node_put(np);

	return ret;
}
core_initcall(mvebu_soc_id_init);