xref: /openbmc/linux/drivers/clk/qcom/hfpll.c (revision e65e175b)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2018, The Linux Foundation. All rights reserved.
3 
4 #include <linux/kernel.h>
5 #include <linux/init.h>
6 #include <linux/module.h>
7 #include <linux/platform_device.h>
8 #include <linux/of.h>
9 #include <linux/clk.h>
10 #include <linux/clk-provider.h>
11 #include <linux/regmap.h>
12 
13 #include "clk-regmap.h"
14 #include "clk-hfpll.h"
15 
16 static const struct hfpll_data hdata = {
17 	.mode_reg = 0x00,
18 	.l_reg = 0x04,
19 	.m_reg = 0x08,
20 	.n_reg = 0x0c,
21 	.user_reg = 0x10,
22 	.config_reg = 0x14,
23 	.config_val = 0x430405d,
24 	.status_reg = 0x1c,
25 	.lock_bit = 16,
26 
27 	.user_val = 0x8,
28 	.user_vco_mask = 0x100000,
29 	.low_vco_max_rate = 1248000000,
30 	.min_rate = 537600000UL,
31 	.max_rate = 2900000000UL,
32 };
33 
34 static const struct of_device_id qcom_hfpll_match_table[] = {
35 	{ .compatible = "qcom,hfpll" },
36 	{ }
37 };
38 MODULE_DEVICE_TABLE(of, qcom_hfpll_match_table);
39 
40 static const struct regmap_config hfpll_regmap_config = {
41 	.reg_bits	= 32,
42 	.reg_stride	= 4,
43 	.val_bits	= 32,
44 	.max_register	= 0x30,
45 	.fast_io	= true,
46 };
47 
48 static int qcom_hfpll_probe(struct platform_device *pdev)
49 {
50 	struct device *dev = &pdev->dev;
51 	void __iomem *base;
52 	struct regmap *regmap;
53 	struct clk_hfpll *h;
54 	struct clk_init_data init = {
55 		.num_parents = 1,
56 		.ops = &clk_ops_hfpll,
57 		/*
58 		 * rather than marking the clock critical and forcing the clock
59 		 * to be always enabled, we make sure that the clock is not
60 		 * disabled: the firmware remains responsible of enabling this
61 		 * clock (for more info check the commit log)
62 		 */
63 		.flags = CLK_IGNORE_UNUSED,
64 	};
65 	int ret;
66 	struct clk_parent_data pdata = { .index = 0 };
67 
68 	h = devm_kzalloc(dev, sizeof(*h), GFP_KERNEL);
69 	if (!h)
70 		return -ENOMEM;
71 
72 	base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
73 	if (IS_ERR(base))
74 		return PTR_ERR(base);
75 
76 	regmap = devm_regmap_init_mmio(&pdev->dev, base, &hfpll_regmap_config);
77 	if (IS_ERR(regmap))
78 		return PTR_ERR(regmap);
79 
80 	if (of_property_read_string_index(dev->of_node, "clock-output-names",
81 					  0, &init.name))
82 		return -ENODEV;
83 
84 	init.parent_data = &pdata;
85 
86 	h->d = &hdata;
87 	h->clkr.hw.init = &init;
88 	spin_lock_init(&h->lock);
89 
90 	ret = devm_clk_register_regmap(dev, &h->clkr);
91 	if (ret) {
92 		dev_err(dev, "failed to register regmap clock: %d\n", ret);
93 		return ret;
94 	}
95 
96 	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
97 					   &h->clkr.hw);
98 }
99 
100 static struct platform_driver qcom_hfpll_driver = {
101 	.probe		= qcom_hfpll_probe,
102 	.driver		= {
103 		.name	= "qcom-hfpll",
104 		.of_match_table = qcom_hfpll_match_table,
105 	},
106 };
107 module_platform_driver(qcom_hfpll_driver);
108 
109 MODULE_DESCRIPTION("QCOM HFPLL Clock Driver");
110 MODULE_LICENSE("GPL v2");
111 MODULE_ALIAS("platform:qcom-hfpll");
112