1 /*
2  * Copyright (c) 2014, NVIDIA CORPORATION.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
15  *
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/of.h>
20 #include <linux/of_address.h>
21 #include <linux/io.h>
22 
23 #include <soc/tegra/fuse.h>
24 
25 #include "fuse.h"
26 
27 #define APBMISC_BASE	0x70000800
28 #define APBMISC_SIZE	0x64
29 #define FUSE_SKU_INFO	0x10
30 
31 static void __iomem *apbmisc_base;
32 static void __iomem *strapping_base;
33 
34 u32 tegra_read_chipid(void)
35 {
36 	return readl_relaxed(apbmisc_base + 4);
37 }
38 
39 u8 tegra_get_chip_id(void)
40 {
41 	if (!apbmisc_base) {
42 		WARN(1, "Tegra Chip ID not yet available\n");
43 		return 0;
44 	}
45 
46 	return (tegra_read_chipid() >> 8) & 0xff;
47 }
48 
49 u32 tegra_read_straps(void)
50 {
51 	if (strapping_base)
52 		return readl_relaxed(strapping_base);
53 	else
54 		return 0;
55 }
56 
57 static const struct of_device_id apbmisc_match[] __initconst = {
58 	{ .compatible = "nvidia,tegra20-apbmisc", },
59 	{},
60 };
61 
62 void __init tegra_init_revision(void)
63 {
64 	u32 id, chip_id, minor_rev;
65 	int rev;
66 
67 	id = tegra_read_chipid();
68 	chip_id = (id >> 8) & 0xff;
69 	minor_rev = (id >> 16) & 0xf;
70 
71 	switch (minor_rev) {
72 	case 1:
73 		rev = TEGRA_REVISION_A01;
74 		break;
75 	case 2:
76 		rev = TEGRA_REVISION_A02;
77 		break;
78 	case 3:
79 		if (chip_id == TEGRA20 && (tegra20_spare_fuse_early(18) ||
80 					   tegra20_spare_fuse_early(19)))
81 			rev = TEGRA_REVISION_A03p;
82 		else
83 			rev = TEGRA_REVISION_A03;
84 		break;
85 	case 4:
86 		rev = TEGRA_REVISION_A04;
87 		break;
88 	default:
89 		rev = TEGRA_REVISION_UNKNOWN;
90 	}
91 
92 	tegra_sku_info.revision = rev;
93 
94 	if (chip_id == TEGRA20)
95 		tegra_sku_info.sku_id = tegra20_fuse_early(FUSE_SKU_INFO);
96 	else
97 		tegra_sku_info.sku_id = tegra30_fuse_readl(FUSE_SKU_INFO);
98 }
99 
100 void __init tegra_init_apbmisc(void)
101 {
102 	struct device_node *np;
103 
104 	np = of_find_matching_node(NULL, apbmisc_match);
105 	apbmisc_base = of_iomap(np, 0);
106 	if (!apbmisc_base) {
107 		pr_warn("ioremap tegra apbmisc failed. using %08x instead\n",
108 			APBMISC_BASE);
109 		apbmisc_base = ioremap(APBMISC_BASE, APBMISC_SIZE);
110 	}
111 
112 	strapping_base = of_iomap(np, 1);
113 	if (!strapping_base)
114 		pr_err("ioremap tegra strapping_base failed\n");
115 }
116