projects/linux·blob master · refs

161 lines · 4.0 KiB

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#include <linux/pm_runtime.h>
14
15#include <soc/tegra/common.h>
16#include <soc/tegra/fuse.h>
17
18static const struct of_device_id tegra_machine_match[] = {
19 { .compatible = "nvidia,tegra20", },
20 { .compatible = "nvidia,tegra30", },
21 { .compatible = "nvidia,tegra114", },
22 { .compatible = "nvidia,tegra124", },
23 { .compatible = "nvidia,tegra132", },
24 { .compatible = "nvidia,tegra210", },
25 { }
26};
27
28bool soc_is_tegra(void)
29{
30 return of_machine_device_match(tegra_machine_match);
31}
32
33static int tegra_core_dev_init_opp_state(struct device *dev)
34{
35 unsigned long rate;
36 struct clk *clk;
37 bool rpm_enabled;
38 int err;
39
40 clk = devm_clk_get(dev, NULL);
41 if (IS_ERR(clk)) {
42 dev_err(dev, "failed to get clk: %pe\n", clk);
43 return PTR_ERR(clk);
44 }
45
46 rate = clk_get_rate(clk);
47 if (!rate) {
48 dev_err(dev, "failed to get clk rate\n");
49 return -EINVAL;
50 }
51
52 /*
53 * Runtime PM of the device must be enabled in order to set up
54 * GENPD's performance properly because GENPD core checks whether
55 * device is suspended and this check doesn't work while RPM is
56 * disabled. This makes sure the OPP vote below gets cached in
57 * GENPD for the device. Instead, the vote is done the next time
58 * the device gets runtime resumed.
59 */
60 rpm_enabled = pm_runtime_enabled(dev);
61 if (!rpm_enabled)
62 pm_runtime_enable(dev);
63
64 /* should never happen in practice */
65 if (!pm_runtime_enabled(dev)) {
66 dev_WARN(dev, "failed to enable runtime PM\n");
67 pm_runtime_disable(dev);
68 return -EINVAL;
69 }
70
71 /* first dummy rate-setting initializes voltage vote */
72 err = dev_pm_opp_set_rate(dev, rate);
73
74 if (!rpm_enabled)
75 pm_runtime_disable(dev);
76
77 if (err) {
78 dev_err(dev, "failed to initialize OPP clock: %d\n", err);
79 return err;
80 }
81
82 return 0;
83}
84
85/**
86 * devm_tegra_core_dev_init_opp_table() - initialize OPP table
87 * @dev: device for which OPP table is initialized
88 * @params: pointer to the OPP table configuration
89 *
90 * This function will initialize OPP table and sync OPP state of a Tegra SoC
91 * core device.
92 *
93 * Return: 0 on success or errorno.
94 */
95int devm_tegra_core_dev_init_opp_table(struct device *dev,
96 struct tegra_core_opp_params *params)
97{
98 u32 hw_version;
99 int err;
100 /*
101 * The clk's connection id to set is NULL and this is a NULL terminated
102 * array, hence two NULL entries.
103 */
104 const char *clk_names[] = { NULL, NULL };
105 struct dev_pm_opp_config config = {
106 /*
107 * For some devices we don't have any OPP table in the DT, and
108 * in order to use the same code path for all the devices, we
109 * create a dummy OPP table for them via this. The dummy OPP
110 * table is only capable of doing clk_set_rate() on invocation
111 * of dev_pm_opp_set_rate() and doesn't provide any other
112 * functionality.
113 */
114 .clk_names = clk_names,
115 };
116
117 if (of_machine_is_compatible("nvidia,tegra20")) {
118 hw_version = BIT(tegra_sku_info.soc_process_id);
119 config.supported_hw = &hw_version;
120 config.supported_hw_count = 1;
121 } else if (of_machine_is_compatible("nvidia,tegra30") ||
122 of_machine_is_compatible("nvidia,tegra114")) {
123 hw_version = BIT(tegra_sku_info.soc_speedo_id);
124 config.supported_hw = &hw_version;
125 config.supported_hw_count = 1;
126 }
127
128 err = devm_pm_opp_set_config(dev, &config);
129 if (err) {
130 dev_err(dev, "failed to set OPP config: %d\n", err);
131 return err;
132 }
133
134 /*
135 * Tegra124+ doesn't support OPP yet, return early for pre-Tegra124
136 * case.
137 */
138 if (!config.supported_hw)
139 return -ENODEV;
140
141 /*
142 * Older device-trees have an empty OPP table, we will get
143 * -ENODEV from devm_pm_opp_of_add_table() in this case.
144 */
145 err = devm_pm_opp_of_add_table(dev);
146 if (err) {
147 if (err != -ENODEV)
148 dev_err(dev, "failed to add OPP table: %d\n", err);
149
150 return err;
151 }
152
153 if (params->init_state) {
154 err = tegra_core_dev_init_opp_state(dev);
155 if (err)
156 return err;
157 }
158
159 return 0;
160}
161EXPORT_SYMBOL_GPL(devm_tegra_core_dev_init_opp_table);