1 /*
2  * Copyright (c) 2013-2015, 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 #include <linux/device.h>
18 #include <linux/kernel.h>
19 #include <linux/bug.h>
20 
21 #include <soc/tegra/fuse.h>
22 
23 #include "fuse.h"
24 
25 #define CPU_PROCESS_CORNERS	2
26 #define GPU_PROCESS_CORNERS	2
27 #define SOC_PROCESS_CORNERS	3
28 
29 #define FUSE_CPU_SPEEDO_0	0x014
30 #define FUSE_CPU_SPEEDO_1	0x02c
31 #define FUSE_CPU_SPEEDO_2	0x030
32 #define FUSE_SOC_SPEEDO_0	0x034
33 #define FUSE_SOC_SPEEDO_1	0x038
34 #define FUSE_SOC_SPEEDO_2	0x03c
35 #define FUSE_CPU_IDDQ		0x018
36 #define FUSE_SOC_IDDQ		0x040
37 #define FUSE_GPU_IDDQ		0x128
38 #define FUSE_FT_REV		0x028
39 
40 enum {
41 	THRESHOLD_INDEX_0,
42 	THRESHOLD_INDEX_1,
43 	THRESHOLD_INDEX_COUNT,
44 };
45 
46 static const u32 __initconst cpu_process_speedos[][CPU_PROCESS_CORNERS] = {
47 	{ 2119, UINT_MAX },
48 	{ 2119, UINT_MAX },
49 };
50 
51 static const u32 __initconst gpu_process_speedos[][GPU_PROCESS_CORNERS] = {
52 	{ UINT_MAX, UINT_MAX },
53 	{ UINT_MAX, UINT_MAX },
54 };
55 
56 static const u32 __initconst soc_process_speedos[][SOC_PROCESS_CORNERS] = {
57 	{ 1950, 2100, UINT_MAX },
58 	{ 1950, 2100, UINT_MAX },
59 };
60 
61 static u8 __init get_speedo_revision(void)
62 {
63 	return tegra_fuse_read_spare(4) << 2 |
64 	       tegra_fuse_read_spare(3) << 1 |
65 	       tegra_fuse_read_spare(2) << 0;
66 }
67 
68 static void __init rev_sku_to_speedo_ids(struct tegra_sku_info *sku_info,
69 					 u8 speedo_rev, int *threshold)
70 {
71 	int sku = sku_info->sku_id;
72 
73 	/* Assign to default */
74 	sku_info->cpu_speedo_id = 0;
75 	sku_info->soc_speedo_id = 0;
76 	sku_info->gpu_speedo_id = 0;
77 	*threshold = THRESHOLD_INDEX_0;
78 
79 	switch (sku) {
80 	case 0x00: /* Engineering SKU */
81 	case 0x01: /* Engineering SKU */
82 	case 0x07:
83 	case 0x17:
84 	case 0x27:
85 		if (speedo_rev >= 2)
86 			sku_info->gpu_speedo_id = 1;
87 		break;
88 
89 	case 0x13:
90 		if (speedo_rev >= 2)
91 			sku_info->gpu_speedo_id = 1;
92 
93 		sku_info->cpu_speedo_id = 1;
94 		break;
95 
96 	default:
97 		pr_err("Tegra210: unknown SKU %#04x\n", sku);
98 		/* Using the default for the error case */
99 		break;
100 	}
101 }
102 
103 static int get_process_id(int value, const u32 *speedos, unsigned int num)
104 {
105 	unsigned int i;
106 
107 	for (i = 0; i < num; i++)
108 		if (value < speedos[num])
109 			return i;
110 
111 	return -EINVAL;
112 }
113 
114 void __init tegra210_init_speedo_data(struct tegra_sku_info *sku_info)
115 {
116 	int cpu_speedo[3], soc_speedo[3], cpu_iddq, gpu_iddq, soc_iddq;
117 	unsigned int index;
118 	u8 speedo_revision;
119 
120 	BUILD_BUG_ON(ARRAY_SIZE(cpu_process_speedos) !=
121 			THRESHOLD_INDEX_COUNT);
122 	BUILD_BUG_ON(ARRAY_SIZE(gpu_process_speedos) !=
123 			THRESHOLD_INDEX_COUNT);
124 	BUILD_BUG_ON(ARRAY_SIZE(soc_process_speedos) !=
125 			THRESHOLD_INDEX_COUNT);
126 
127 	/* Read speedo/IDDQ fuses */
128 	cpu_speedo[0] = tegra_fuse_read_early(FUSE_CPU_SPEEDO_0);
129 	cpu_speedo[1] = tegra_fuse_read_early(FUSE_CPU_SPEEDO_1);
130 	cpu_speedo[2] = tegra_fuse_read_early(FUSE_CPU_SPEEDO_2);
131 
132 	soc_speedo[0] = tegra_fuse_read_early(FUSE_SOC_SPEEDO_0);
133 	soc_speedo[1] = tegra_fuse_read_early(FUSE_SOC_SPEEDO_1);
134 	soc_speedo[2] = tegra_fuse_read_early(FUSE_CPU_SPEEDO_2);
135 
136 	cpu_iddq = tegra_fuse_read_early(FUSE_CPU_IDDQ) * 4;
137 	soc_iddq = tegra_fuse_read_early(FUSE_SOC_IDDQ) * 4;
138 	gpu_iddq = tegra_fuse_read_early(FUSE_GPU_IDDQ) * 5;
139 
140 	/*
141 	 * Determine CPU, GPU and SoC speedo values depending on speedo fusing
142 	 * revision. Note that GPU speedo value is fused in CPU_SPEEDO_2.
143 	 */
144 	speedo_revision = get_speedo_revision();
145 	pr_info("Speedo Revision %u\n", speedo_revision);
146 
147 	if (speedo_revision >= 3) {
148 		sku_info->cpu_speedo_value = cpu_speedo[0];
149 		sku_info->gpu_speedo_value = cpu_speedo[2];
150 		sku_info->soc_speedo_value = soc_speedo[0];
151 	} else if (speedo_revision == 2) {
152 		sku_info->cpu_speedo_value = (-1938 + (1095 * cpu_speedo[0] / 100)) / 10;
153 		sku_info->gpu_speedo_value = (-1662 + (1082 * cpu_speedo[2] / 100)) / 10;
154 		sku_info->soc_speedo_value = ( -705 + (1037 * soc_speedo[0] / 100)) / 10;
155 	} else {
156 		sku_info->cpu_speedo_value = 2100;
157 		sku_info->gpu_speedo_value = cpu_speedo[2] - 75;
158 		sku_info->soc_speedo_value = 1900;
159 	}
160 
161 	if ((sku_info->cpu_speedo_value <= 0) ||
162 	    (sku_info->gpu_speedo_value <= 0) ||
163 	    (sku_info->soc_speedo_value <= 0)) {
164 		WARN(1, "speedo value not fused\n");
165 		return;
166 	}
167 
168 	rev_sku_to_speedo_ids(sku_info, speedo_revision, &index);
169 
170 	sku_info->gpu_process_id = get_process_id(sku_info->gpu_speedo_value,
171 						  gpu_process_speedos[index],
172 						  GPU_PROCESS_CORNERS);
173 
174 	sku_info->cpu_process_id = get_process_id(sku_info->cpu_speedo_value,
175 						  cpu_process_speedos[index],
176 						  CPU_PROCESS_CORNERS);
177 
178 	sku_info->soc_process_id = get_process_id(sku_info->soc_speedo_value,
179 						  soc_process_speedos[index],
180 						  SOC_PROCESS_CORNERS);
181 
182 	pr_debug("Tegra GPU Speedo ID=%d, Speedo Value=%d\n",
183 		 sku_info->gpu_speedo_id, sku_info->gpu_speedo_value);
184 }
185