xref: /linux/drivers/soc/tegra/common.c (revision 5d8dfaa71d87f742c53309b95cb6a8b274119027)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014 NVIDIA CORPORATION.  All rights reserved.
4  */
5 
6 #define dev_fmt(fmt)	"tegra-soc: " fmt
7 
8 #include <linux/clk.h>
9 #include <linux/device.h>
10 #include <linux/export.h>
11 #include <linux/of.h>
12 #include <linux/pm_opp.h>
13 
14 #include <soc/tegra/common.h>
15 #include <soc/tegra/fuse.h>
16 
17 static const struct of_device_id tegra_machine_match[] = {
18 	{ .compatible = "nvidia,tegra20", },
19 	{ .compatible = "nvidia,tegra30", },
20 	{ .compatible = "nvidia,tegra114", },
21 	{ .compatible = "nvidia,tegra124", },
22 	{ .compatible = "nvidia,tegra132", },
23 	{ .compatible = "nvidia,tegra210", },
24 	{ }
25 };
26 
27 bool soc_is_tegra(void)
28 {
29 	const struct of_device_id *match;
30 	struct device_node *root;
31 
32 	root = of_find_node_by_path("/");
33 	if (!root)
34 		return false;
35 
36 	match = of_match_node(tegra_machine_match, root);
37 	of_node_put(root);
38 
39 	return match != NULL;
40 }
41 
42 static int tegra_core_dev_init_opp_state(struct device *dev)
43 {
44 	unsigned long rate;
45 	struct clk *clk;
46 	int err;
47 
48 	clk = devm_clk_get(dev, NULL);
49 	if (IS_ERR(clk)) {
50 		dev_err(dev, "failed to get clk: %pe\n", clk);
51 		return PTR_ERR(clk);
52 	}
53 
54 	rate = clk_get_rate(clk);
55 	if (!rate) {
56 		dev_err(dev, "failed to get clk rate\n");
57 		return -EINVAL;
58 	}
59 
60 	/* first dummy rate-setting initializes voltage vote */
61 	err = dev_pm_opp_set_rate(dev, rate);
62 	if (err) {
63 		dev_err(dev, "failed to initialize OPP clock: %d\n", err);
64 		return err;
65 	}
66 
67 	return 0;
68 }
69 
70 /**
71  * devm_tegra_core_dev_init_opp_table() - initialize OPP table
72  * @dev: device for which OPP table is initialized
73  * @params: pointer to the OPP table configuration
74  *
75  * This function will initialize OPP table and sync OPP state of a Tegra SoC
76  * core device.
77  *
78  * Return: 0 on success or errorno.
79  */
80 int devm_tegra_core_dev_init_opp_table(struct device *dev,
81 				       struct tegra_core_opp_params *params)
82 {
83 	u32 hw_version;
84 	int err;
85 
86 	err = devm_pm_opp_set_clkname(dev, NULL);
87 	if (err) {
88 		dev_err(dev, "failed to set OPP clk: %d\n", err);
89 		return err;
90 	}
91 
92 	/* Tegra114+ doesn't support OPP yet */
93 	if (!of_machine_is_compatible("nvidia,tegra20") &&
94 	    !of_machine_is_compatible("nvidia,tegra30"))
95 		return -ENODEV;
96 
97 	if (of_machine_is_compatible("nvidia,tegra20"))
98 		hw_version = BIT(tegra_sku_info.soc_process_id);
99 	else
100 		hw_version = BIT(tegra_sku_info.soc_speedo_id);
101 
102 	err = devm_pm_opp_set_supported_hw(dev, &hw_version, 1);
103 	if (err) {
104 		dev_err(dev, "failed to set OPP supported HW: %d\n", err);
105 		return err;
106 	}
107 
108 	/*
109 	 * Older device-trees have an empty OPP table, we will get
110 	 * -ENODEV from devm_pm_opp_of_add_table() in this case.
111 	 */
112 	err = devm_pm_opp_of_add_table(dev);
113 	if (err) {
114 		if (err == -ENODEV)
115 			dev_err_once(dev, "OPP table not found, please update device-tree\n");
116 		else
117 			dev_err(dev, "failed to add OPP table: %d\n", err);
118 
119 		return err;
120 	}
121 
122 	if (params->init_state) {
123 		err = tegra_core_dev_init_opp_state(dev);
124 		if (err)
125 			return err;
126 	}
127 
128 	return 0;
129 }
130 EXPORT_SYMBOL_GPL(devm_tegra_core_dev_init_opp_table);
131