1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2010 Google, Inc.
4  *
5  * Author:
6  *	Colin Cross <ccross@google.com>
7  *	Based on arch/arm/plat-omap/cpu-omap.c, (C) 2005 Nokia Corporation
8  */
9 
10 #include <linux/bits.h>
11 #include <linux/cpu.h>
12 #include <linux/err.h>
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/of_device.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_opp.h>
18 #include <linux/types.h>
19 
20 #include <soc/tegra/common.h>
21 #include <soc/tegra/fuse.h>
22 
23 static bool cpu0_node_has_opp_v2_prop(void)
24 {
25 	struct device_node *np = of_cpu_device_node_get(0);
26 	bool ret = false;
27 
28 	if (of_get_property(np, "operating-points-v2", NULL))
29 		ret = true;
30 
31 	of_node_put(np);
32 	return ret;
33 }
34 
35 static int tegra20_cpufreq_probe(struct platform_device *pdev)
36 {
37 	struct platform_device *cpufreq_dt;
38 	struct opp_table *opp_table;
39 	struct device *cpu_dev;
40 	u32 versions[2];
41 	int err;
42 
43 	if (!cpu0_node_has_opp_v2_prop()) {
44 		dev_err(&pdev->dev, "operating points not found\n");
45 		dev_err(&pdev->dev, "please update your device tree\n");
46 		return -ENODEV;
47 	}
48 
49 	if (of_machine_is_compatible("nvidia,tegra20")) {
50 		versions[0] = BIT(tegra_sku_info.cpu_process_id);
51 		versions[1] = BIT(tegra_sku_info.soc_speedo_id);
52 	} else {
53 		versions[0] = BIT(tegra_sku_info.cpu_process_id);
54 		versions[1] = BIT(tegra_sku_info.cpu_speedo_id);
55 	}
56 
57 	dev_info(&pdev->dev, "hardware version 0x%x 0x%x\n",
58 		 versions[0], versions[1]);
59 
60 	cpu_dev = get_cpu_device(0);
61 	if (WARN_ON(!cpu_dev))
62 		return -ENODEV;
63 
64 	opp_table = dev_pm_opp_set_supported_hw(cpu_dev, versions, 2);
65 	err = PTR_ERR_OR_ZERO(opp_table);
66 	if (err) {
67 		dev_err(&pdev->dev, "failed to set supported hw: %d\n", err);
68 		return err;
69 	}
70 
71 	cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
72 	err = PTR_ERR_OR_ZERO(cpufreq_dt);
73 	if (err) {
74 		dev_err(&pdev->dev,
75 			"failed to create cpufreq-dt device: %d\n", err);
76 		goto err_put_supported_hw;
77 	}
78 
79 	platform_set_drvdata(pdev, cpufreq_dt);
80 
81 	return 0;
82 
83 err_put_supported_hw:
84 	dev_pm_opp_put_supported_hw(opp_table);
85 
86 	return err;
87 }
88 
89 static int tegra20_cpufreq_remove(struct platform_device *pdev)
90 {
91 	struct platform_device *cpufreq_dt;
92 	struct opp_table *opp_table;
93 
94 	cpufreq_dt = platform_get_drvdata(pdev);
95 	platform_device_unregister(cpufreq_dt);
96 
97 	opp_table = dev_pm_opp_get_opp_table(get_cpu_device(0));
98 	dev_pm_opp_put_supported_hw(opp_table);
99 	dev_pm_opp_put_opp_table(opp_table);
100 
101 	return 0;
102 }
103 
104 static struct platform_driver tegra20_cpufreq_driver = {
105 	.probe		= tegra20_cpufreq_probe,
106 	.remove		= tegra20_cpufreq_remove,
107 	.driver		= {
108 		.name	= "tegra20-cpufreq",
109 	},
110 };
111 module_platform_driver(tegra20_cpufreq_driver);
112 
113 MODULE_ALIAS("platform:tegra20-cpufreq");
114 MODULE_AUTHOR("Colin Cross <ccross@android.com>");
115 MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver");
116 MODULE_LICENSE("GPL");
117