summaryrefslogtreecommitdiff
path: root/drivers/cpufreq/qcom-cpufreq-kryo.c
blob: dd64dcf89c74c26a3d93924e2906a631757c292b (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
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2018, The Linux Foundation. All rights reserved.
 */

/*
 * In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors,
 * the CPU frequency subset and voltage value of each OPP varies
 * based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables
 * defines the voltage and frequency value based on the msm-id in SMEM
 * and speedbin blown in the efuse combination.
 * The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC
 * to provide the OPP framework with required information.
 * This is used to determine the voltage and frequency value for each OPP of
 * operating-points-v2 table when it is parsed by the OPP framework.
 */

#include <linux/cpu.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/nvmem-consumer.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_opp.h>
#include <linux/slab.h>
#include <linux/soc/qcom/smem.h>

#define MSM_ID_SMEM	137

enum _msm_id {
	MSM8996V3 = 0xF6ul,
	APQ8096V3 = 0x123ul,
	MSM8996SG = 0x131ul,
	APQ8096SG = 0x138ul,
};

enum _msm8996_version {
	MSM8996_V3,
	MSM8996_SG,
	NUM_OF_MSM8996_VERSIONS,
};

static struct platform_device *cpufreq_dt_pdev, *kryo_cpufreq_pdev;

static enum _msm8996_version qcom_cpufreq_kryo_get_msm_id(void)
{
	size_t len;
	u32 *msm_id;
	enum _msm8996_version version;

	msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, MSM_ID_SMEM, &len);
	if (IS_ERR(msm_id))
		return NUM_OF_MSM8996_VERSIONS;

	/* The first 4 bytes are format, next to them is the actual msm-id */
	msm_id++;

	switch ((enum _msm_id)*msm_id) {
	case MSM8996V3:
	case APQ8096V3:
		version = MSM8996_V3;
		break;
	case MSM8996SG:
	case APQ8096SG:
		version = MSM8996_SG;
		break;
	default:
		version = NUM_OF_MSM8996_VERSIONS;
	}

	return version;
}

static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
{
	struct opp_table **opp_tables;
	enum _msm8996_version msm8996_version;
	struct nvmem_cell *speedbin_nvmem;
	struct device_node *np;
	struct device *cpu_dev;
	unsigned cpu;
	u8 *speedbin;
	u32 versions;
	size_t len;
	int ret;

	cpu_dev = get_cpu_device(0);
	if (!cpu_dev)
		return -ENODEV;

	msm8996_version = qcom_cpufreq_kryo_get_msm_id();
	if (NUM_OF_MSM8996_VERSIONS == msm8996_version) {
		dev_err(cpu_dev, "Not Snapdragon 820/821!");
		return -ENODEV;
	}

	np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
	if (!np)
		return -ENOENT;

	ret = of_device_is_compatible(np, "operating-points-v2-kryo-cpu");
	if (!ret) {
		of_node_put(np);
		return -ENOENT;
	}

	speedbin_nvmem = of_nvmem_cell_get(np, NULL);
	of_node_put(np);
	if (IS_ERR(speedbin_nvmem)) {
		if (PTR_ERR(speedbin_nvmem) != -EPROBE_DEFER)
			dev_err(cpu_dev, "Could not get nvmem cell: %ld\n",
				PTR_ERR(speedbin_nvmem));
		return PTR_ERR(speedbin_nvmem);
	}

	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
	nvmem_cell_put(speedbin_nvmem);
	if (IS_ERR(speedbin))
		return PTR_ERR(speedbin);

	switch (msm8996_version) {
	case MSM8996_V3:
		versions = 1 << (unsigned int)(*speedbin);
		break;
	case MSM8996_SG:
		versions = 1 << ((unsigned int)(*speedbin) + 4);
		break;
	default:
		BUG();
		break;
	}
	kfree(speedbin);

	opp_tables = kcalloc(num_possible_cpus(), sizeof(*opp_tables), GFP_KERNEL);
	if (!opp_tables)
		return -ENOMEM;

	for_each_possible_cpu(cpu) {
		cpu_dev = get_cpu_device(cpu);
		if (NULL == cpu_dev) {
			ret = -ENODEV;
			goto free_opp;
		}

		opp_tables[cpu] = dev_pm_opp_set_supported_hw(cpu_dev,
							      &versions, 1);
		if (IS_ERR(opp_tables[cpu])) {
			ret = PTR_ERR(opp_tables[cpu]);
			dev_err(cpu_dev, "Failed to set supported hardware\n");
			goto free_opp;
		}
	}

	cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1,
							  NULL, 0);
	if (!IS_ERR(cpufreq_dt_pdev)) {
		platform_set_drvdata(pdev, opp_tables);
		return 0;
	}

	ret = PTR_ERR(cpufreq_dt_pdev);
	dev_err(cpu_dev, "Failed to register platform device\n");

free_opp:
	for_each_possible_cpu(cpu) {
		if (IS_ERR_OR_NULL(opp_tables[cpu]))
			break;
		dev_pm_opp_put_supported_hw(opp_tables[cpu]);
	}
	kfree(opp_tables);

	return ret;
}

static int qcom_cpufreq_kryo_remove(struct platform_device *pdev)
{
	struct opp_table **opp_tables = platform_get_drvdata(pdev);
	unsigned int cpu;

	platform_device_unregister(cpufreq_dt_pdev);

	for_each_possible_cpu(cpu)
		dev_pm_opp_put_supported_hw(opp_tables[cpu]);

	kfree(opp_tables);

	return 0;
}

static struct platform_driver qcom_cpufreq_kryo_driver = {
	.probe = qcom_cpufreq_kryo_probe,
	.remove = qcom_cpufreq_kryo_remove,
	.driver = {
		.name = "qcom-cpufreq-kryo",
	},
};

static const struct of_device_id qcom_cpufreq_kryo_match_list[] __initconst = {
	{ .compatible = "qcom,apq8096", },
	{ .compatible = "qcom,msm8996", },
	{}
};

/*
 * Since the driver depends on smem and nvmem drivers, which may
 * return EPROBE_DEFER, all the real activity is done in the probe,
 * which may be defered as well. The init here is only registering
 * the driver and the platform device.
 */
static int __init qcom_cpufreq_kryo_init(void)
{
	struct device_node *np = of_find_node_by_path("/");
	const struct of_device_id *match;
	int ret;

	if (!np)
		return -ENODEV;

	match = of_match_node(qcom_cpufreq_kryo_match_list, np);
	of_node_put(np);
	if (!match)
		return -ENODEV;

	ret = platform_driver_register(&qcom_cpufreq_kryo_driver);
	if (unlikely(ret < 0))
		return ret;

	kryo_cpufreq_pdev = platform_device_register_simple(
		"qcom-cpufreq-kryo", -1, NULL, 0);
	ret = PTR_ERR_OR_ZERO(kryo_cpufreq_pdev);
	if (0 == ret)
		return 0;

	platform_driver_unregister(&qcom_cpufreq_kryo_driver);
	return ret;
}
module_init(qcom_cpufreq_kryo_init);

static void __exit qcom_cpufreq_kryo_exit(void)
{
	platform_device_unregister(kryo_cpufreq_pdev);
	platform_driver_unregister(&qcom_cpufreq_kryo_driver);
}
module_exit(qcom_cpufreq_kryo_exit);

MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Kryo CPUfreq driver");
MODULE_LICENSE("GPL v2");