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_property_present(np, "operating-points-v2"))
29 		ret = true;
30 
31 	of_node_put(np);
32 	return ret;
33 }
34 
35 static void tegra20_cpufreq_put_supported_hw(void *opp_token)
36 {
37 	dev_pm_opp_put_supported_hw((unsigned long) opp_token);
38 }
39 
40 static void tegra20_cpufreq_dt_unregister(void *cpufreq_dt)
41 {
42 	platform_device_unregister(cpufreq_dt);
43 }
44 
45 static int tegra20_cpufreq_probe(struct platform_device *pdev)
46 {
47 	struct platform_device *cpufreq_dt;
48 	struct device *cpu_dev;
49 	u32 versions[2];
50 	int err;
51 
52 	if (!cpu0_node_has_opp_v2_prop()) {
53 		dev_err(&pdev->dev, "operating points not found\n");
54 		dev_err(&pdev->dev, "please update your device tree\n");
55 		return -ENODEV;
56 	}
57 
58 	if (of_machine_is_compatible("nvidia,tegra20")) {
59 		versions[0] = BIT(tegra_sku_info.cpu_process_id);
60 		versions[1] = BIT(tegra_sku_info.soc_speedo_id);
61 	} else {
62 		versions[0] = BIT(tegra_sku_info.cpu_process_id);
63 		versions[1] = BIT(tegra_sku_info.cpu_speedo_id);
64 	}
65 
66 	dev_info(&pdev->dev, "hardware version 0x%x 0x%x\n",
67 		 versions[0], versions[1]);
68 
69 	cpu_dev = get_cpu_device(0);
70 	if (WARN_ON(!cpu_dev))
71 		return -ENODEV;
72 
73 	err = dev_pm_opp_set_supported_hw(cpu_dev, versions, 2);
74 	if (err < 0) {
75 		dev_err(&pdev->dev, "failed to set supported hw: %d\n", err);
76 		return err;
77 	}
78 
79 	err = devm_add_action_or_reset(&pdev->dev,
80 				       tegra20_cpufreq_put_supported_hw,
81 				       (void *)((unsigned long) err));
82 	if (err)
83 		return err;
84 
85 	cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
86 	err = PTR_ERR_OR_ZERO(cpufreq_dt);
87 	if (err) {
88 		dev_err(&pdev->dev,
89 			"failed to create cpufreq-dt device: %d\n", err);
90 		return err;
91 	}
92 
93 	err = devm_add_action_or_reset(&pdev->dev,
94 				       tegra20_cpufreq_dt_unregister,
95 				       cpufreq_dt);
96 	if (err)
97 		return err;
98 
99 	return 0;
100 }
101 
102 static struct platform_driver tegra20_cpufreq_driver = {
103 	.probe		= tegra20_cpufreq_probe,
104 	.driver		= {
105 		.name	= "tegra20-cpufreq",
106 	},
107 };
108 module_platform_driver(tegra20_cpufreq_driver);
109 
110 MODULE_ALIAS("platform:tegra20-cpufreq");
111 MODULE_AUTHOR("Colin Cross <ccross@android.com>");
112 MODULE_DESCRIPTION("NVIDIA Tegra20 cpufreq driver");
113 MODULE_LICENSE("GPL");
114