1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Clock driver for the ARM Integrator/IM-PD1 board
4  * Copyright (C) 2012-2013 Linus Walleij
5  */
6 #include <linux/clk-provider.h>
7 #include <linux/clkdev.h>
8 #include <linux/err.h>
9 #include <linux/io.h>
10 #include <linux/platform_device.h>
11 #include <linux/platform_data/clk-integrator.h>
12 #include <linux/module.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/regmap.h>
15 
16 #include "icst.h"
17 #include "clk-icst.h"
18 
19 #define IMPD1_OSC1	0x00
20 #define IMPD1_OSC2	0x04
21 #define IMPD1_LOCK	0x08
22 
23 struct impd1_clk {
24 	char *pclkname;
25 	struct clk *pclk;
26 	char *vco1name;
27 	struct clk *vco1clk;
28 	char *vco2name;
29 	struct clk *vco2clk;
30 	struct clk *mmciclk;
31 	char *uartname;
32 	struct clk *uartclk;
33 	char *spiname;
34 	struct clk *spiclk;
35 	char *scname;
36 	struct clk *scclk;
37 	struct clk_lookup *clks[15];
38 };
39 
40 /* One entry for each connected IM-PD1 LM */
41 static struct impd1_clk impd1_clks[4];
42 
43 /*
44  * There are two VCO's on the IM-PD1
45  */
46 
47 static const struct icst_params impd1_vco1_params = {
48 	.ref		= 24000000,	/* 24 MHz */
49 	.vco_max	= ICST525_VCO_MAX_3V,
50 	.vco_min	= ICST525_VCO_MIN,
51 	.vd_min		= 12,
52 	.vd_max		= 519,
53 	.rd_min		= 3,
54 	.rd_max		= 120,
55 	.s2div		= icst525_s2div,
56 	.idx2s		= icst525_idx2s,
57 };
58 
59 static const struct clk_icst_desc impd1_icst1_desc = {
60 	.params = &impd1_vco1_params,
61 	.vco_offset = IMPD1_OSC1,
62 	.lock_offset = IMPD1_LOCK,
63 };
64 
65 static const struct icst_params impd1_vco2_params = {
66 	.ref		= 24000000,	/* 24 MHz */
67 	.vco_max	= ICST525_VCO_MAX_3V,
68 	.vco_min	= ICST525_VCO_MIN,
69 	.vd_min		= 12,
70 	.vd_max		= 519,
71 	.rd_min		= 3,
72 	.rd_max		= 120,
73 	.s2div		= icst525_s2div,
74 	.idx2s		= icst525_idx2s,
75 };
76 
77 static const struct clk_icst_desc impd1_icst2_desc = {
78 	.params = &impd1_vco2_params,
79 	.vco_offset = IMPD1_OSC2,
80 	.lock_offset = IMPD1_LOCK,
81 };
82 
83 /**
84  * integrator_impd1_clk_init() - set up the integrator clock tree
85  * @base: base address of the logic module (LM)
86  * @id: the ID of this LM
87  */
88 void integrator_impd1_clk_init(void __iomem *base, unsigned int id)
89 {
90 	struct impd1_clk *imc;
91 	struct clk *clk;
92 	struct clk *pclk;
93 	int i;
94 
95 	if (id > 3) {
96 		pr_crit("no more than 4 LMs can be attached\n");
97 		return;
98 	}
99 	imc = &impd1_clks[id];
100 
101 	/* Register the fixed rate PCLK */
102 	imc->pclkname = kasprintf(GFP_KERNEL, "lm%x-pclk", id);
103 	pclk = clk_register_fixed_rate(NULL, imc->pclkname, NULL, 0, 0);
104 	imc->pclk = pclk;
105 
106 	imc->vco1name = kasprintf(GFP_KERNEL, "lm%x-vco1", id);
107 	clk = icst_clk_register(NULL, &impd1_icst1_desc, imc->vco1name, NULL,
108 				base);
109 	imc->vco1clk = clk;
110 	imc->clks[0] = clkdev_alloc(pclk, "apb_pclk", "lm%x:01000", id);
111 	imc->clks[1] = clkdev_alloc(clk, NULL, "lm%x:01000", id);
112 
113 	/* VCO2 is also called "CLK2" */
114 	imc->vco2name = kasprintf(GFP_KERNEL, "lm%x-vco2", id);
115 	clk = icst_clk_register(NULL, &impd1_icst2_desc, imc->vco2name, NULL,
116 				base);
117 	imc->vco2clk = clk;
118 
119 	/* MMCI uses CLK2 right off */
120 	imc->clks[2] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00700", id);
121 	imc->clks[3] = clkdev_alloc(clk, NULL, "lm%x:00700", id);
122 
123 	/* UART reference clock divides CLK2 by a fixed factor 4 */
124 	imc->uartname = kasprintf(GFP_KERNEL, "lm%x-uartclk", id);
125 	clk = clk_register_fixed_factor(NULL, imc->uartname, imc->vco2name,
126 				   CLK_IGNORE_UNUSED, 1, 4);
127 	imc->uartclk = clk;
128 	imc->clks[4] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00100", id);
129 	imc->clks[5] = clkdev_alloc(clk, NULL, "lm%x:00100", id);
130 	imc->clks[6] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00200", id);
131 	imc->clks[7] = clkdev_alloc(clk, NULL, "lm%x:00200", id);
132 
133 	/* SPI PL022 clock divides CLK2 by a fixed factor 64 */
134 	imc->spiname = kasprintf(GFP_KERNEL, "lm%x-spiclk", id);
135 	clk = clk_register_fixed_factor(NULL, imc->spiname, imc->vco2name,
136 				   CLK_IGNORE_UNUSED, 1, 64);
137 	imc->clks[8] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00300", id);
138 	imc->clks[9] = clkdev_alloc(clk, NULL, "lm%x:00300", id);
139 
140 	/* The GPIO blocks and AACI have only PCLK */
141 	imc->clks[10] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00400", id);
142 	imc->clks[11] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00500", id);
143 	imc->clks[12] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00800", id);
144 
145 	/* Smart Card clock divides CLK2 by a fixed factor 4 */
146 	imc->scname = kasprintf(GFP_KERNEL, "lm%x-scclk", id);
147 	clk = clk_register_fixed_factor(NULL, imc->scname, imc->vco2name,
148 				   CLK_IGNORE_UNUSED, 1, 4);
149 	imc->scclk = clk;
150 	imc->clks[13] = clkdev_alloc(pclk, "apb_pclk", "lm%x:00600", id);
151 	imc->clks[14] = clkdev_alloc(clk, NULL, "lm%x:00600", id);
152 
153 	for (i = 0; i < ARRAY_SIZE(imc->clks); i++)
154 		clkdev_add(imc->clks[i]);
155 }
156 EXPORT_SYMBOL_GPL(integrator_impd1_clk_init);
157 
158 void integrator_impd1_clk_exit(unsigned int id)
159 {
160 	int i;
161 	struct impd1_clk *imc;
162 
163 	if (id > 3)
164 		return;
165 	imc = &impd1_clks[id];
166 
167 	for (i = 0; i < ARRAY_SIZE(imc->clks); i++)
168 		clkdev_drop(imc->clks[i]);
169 	clk_unregister(imc->spiclk);
170 	clk_unregister(imc->uartclk);
171 	clk_unregister(imc->vco2clk);
172 	clk_unregister(imc->vco1clk);
173 	clk_unregister(imc->pclk);
174 	kfree(imc->scname);
175 	kfree(imc->spiname);
176 	kfree(imc->uartname);
177 	kfree(imc->vco2name);
178 	kfree(imc->vco1name);
179 	kfree(imc->pclkname);
180 }
181 EXPORT_SYMBOL_GPL(integrator_impd1_clk_exit);
182 
183 static int integrator_impd1_clk_spawn(struct device *dev,
184 				      struct device_node *parent,
185 				      struct device_node *np)
186 {
187 	struct regmap *map;
188 	struct clk *clk = ERR_PTR(-EINVAL);
189 	const char *name = np->name;
190 	const char *parent_name;
191 	const struct clk_icst_desc *desc;
192 	int ret;
193 
194 	map = syscon_node_to_regmap(parent);
195 	if (IS_ERR(map)) {
196 		pr_err("no regmap for syscon IM-PD1 ICST clock parent\n");
197 		return PTR_ERR(map);
198 	}
199 
200 	if (of_device_is_compatible(np, "arm,impd1-vco1")) {
201 		desc = &impd1_icst1_desc;
202 	} else if (of_device_is_compatible(np, "arm,impd1-vco2")) {
203 		desc = &impd1_icst2_desc;
204 	} else {
205 		dev_err(dev, "not a clock node %s\n", name);
206 		return -ENODEV;
207 	}
208 
209 	of_property_read_string(np, "clock-output-names", &name);
210 	parent_name = of_clk_get_parent_name(np, 0);
211 	clk = icst_clk_setup(NULL, desc, name, parent_name, map,
212 			     ICST_INTEGRATOR_IM_PD1);
213 	if (!IS_ERR(clk)) {
214 		of_clk_add_provider(np, of_clk_src_simple_get, clk);
215 		ret = 0;
216 	} else {
217 		dev_err(dev, "error setting up IM-PD1 ICST clock\n");
218 		ret = PTR_ERR(clk);
219 	}
220 
221 	return ret;
222 }
223 
224 static int integrator_impd1_clk_probe(struct platform_device *pdev)
225 {
226 	struct device *dev = &pdev->dev;
227 	struct device_node *np = dev->of_node;
228 	struct device_node *child;
229 	int ret = 0;
230 
231 	for_each_available_child_of_node(np, child) {
232 		ret = integrator_impd1_clk_spawn(dev, np, child);
233 		if (ret)
234 			break;
235 	}
236 
237 	return ret;
238 }
239 
240 static const struct of_device_id impd1_syscon_match[] = {
241 	{ .compatible = "arm,im-pd1-syscon", },
242 	{}
243 };
244 MODULE_DEVICE_TABLE(of, impd1_syscon_match);
245 
246 static struct platform_driver impd1_clk_driver = {
247 	.driver = {
248 		.name = "impd1-clk",
249 		.of_match_table = impd1_syscon_match,
250 	},
251 	.probe  = integrator_impd1_clk_probe,
252 };
253 builtin_platform_driver(impd1_clk_driver);
254 
255 MODULE_AUTHOR("Linus Walleij <linusw@kernel.org>");
256 MODULE_DESCRIPTION("Arm IM-PD1 module clock driver");
257 MODULE_LICENSE("GPL v2");
258