xref: /openbmc/linux/drivers/clk/tegra/clk.c (revision 9e3bd0f6)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
4  */
5 
6 #include <linux/clkdev.h>
7 #include <linux/clk.h>
8 #include <linux/clk-provider.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/of.h>
12 #include <linux/clk/tegra.h>
13 #include <linux/reset-controller.h>
14 
15 #include <soc/tegra/fuse.h>
16 
17 #include "clk.h"
18 
19 #define CLK_OUT_ENB_L			0x010
20 #define CLK_OUT_ENB_H			0x014
21 #define CLK_OUT_ENB_U			0x018
22 #define CLK_OUT_ENB_V			0x360
23 #define CLK_OUT_ENB_W			0x364
24 #define CLK_OUT_ENB_X			0x280
25 #define CLK_OUT_ENB_Y			0x298
26 #define CLK_OUT_ENB_SET_L		0x320
27 #define CLK_OUT_ENB_CLR_L		0x324
28 #define CLK_OUT_ENB_SET_H		0x328
29 #define CLK_OUT_ENB_CLR_H		0x32c
30 #define CLK_OUT_ENB_SET_U		0x330
31 #define CLK_OUT_ENB_CLR_U		0x334
32 #define CLK_OUT_ENB_SET_V		0x440
33 #define CLK_OUT_ENB_CLR_V		0x444
34 #define CLK_OUT_ENB_SET_W		0x448
35 #define CLK_OUT_ENB_CLR_W		0x44c
36 #define CLK_OUT_ENB_SET_X		0x284
37 #define CLK_OUT_ENB_CLR_X		0x288
38 #define CLK_OUT_ENB_SET_Y		0x29c
39 #define CLK_OUT_ENB_CLR_Y		0x2a0
40 
41 #define RST_DEVICES_L			0x004
42 #define RST_DEVICES_H			0x008
43 #define RST_DEVICES_U			0x00C
44 #define RST_DEVICES_V			0x358
45 #define RST_DEVICES_W			0x35C
46 #define RST_DEVICES_X			0x28C
47 #define RST_DEVICES_Y			0x2a4
48 #define RST_DEVICES_SET_L		0x300
49 #define RST_DEVICES_CLR_L		0x304
50 #define RST_DEVICES_SET_H		0x308
51 #define RST_DEVICES_CLR_H		0x30c
52 #define RST_DEVICES_SET_U		0x310
53 #define RST_DEVICES_CLR_U		0x314
54 #define RST_DEVICES_SET_V		0x430
55 #define RST_DEVICES_CLR_V		0x434
56 #define RST_DEVICES_SET_W		0x438
57 #define RST_DEVICES_CLR_W		0x43c
58 #define RST_DEVICES_SET_X		0x290
59 #define RST_DEVICES_CLR_X		0x294
60 #define RST_DEVICES_SET_Y		0x2a8
61 #define RST_DEVICES_CLR_Y		0x2ac
62 
63 /* Global data of Tegra CPU CAR ops */
64 static struct tegra_cpu_car_ops dummy_car_ops;
65 struct tegra_cpu_car_ops *tegra_cpu_car_ops = &dummy_car_ops;
66 
67 int *periph_clk_enb_refcnt;
68 static int periph_banks;
69 static struct clk **clks;
70 static int clk_num;
71 static struct clk_onecell_data clk_data;
72 
73 /* Handlers for SoC-specific reset lines */
74 static int (*special_reset_assert)(unsigned long);
75 static int (*special_reset_deassert)(unsigned long);
76 static unsigned int num_special_reset;
77 
78 static const struct tegra_clk_periph_regs periph_regs[] = {
79 	[0] = {
80 		.enb_reg = CLK_OUT_ENB_L,
81 		.enb_set_reg = CLK_OUT_ENB_SET_L,
82 		.enb_clr_reg = CLK_OUT_ENB_CLR_L,
83 		.rst_reg = RST_DEVICES_L,
84 		.rst_set_reg = RST_DEVICES_SET_L,
85 		.rst_clr_reg = RST_DEVICES_CLR_L,
86 	},
87 	[1] = {
88 		.enb_reg = CLK_OUT_ENB_H,
89 		.enb_set_reg = CLK_OUT_ENB_SET_H,
90 		.enb_clr_reg = CLK_OUT_ENB_CLR_H,
91 		.rst_reg = RST_DEVICES_H,
92 		.rst_set_reg = RST_DEVICES_SET_H,
93 		.rst_clr_reg = RST_DEVICES_CLR_H,
94 	},
95 	[2] = {
96 		.enb_reg = CLK_OUT_ENB_U,
97 		.enb_set_reg = CLK_OUT_ENB_SET_U,
98 		.enb_clr_reg = CLK_OUT_ENB_CLR_U,
99 		.rst_reg = RST_DEVICES_U,
100 		.rst_set_reg = RST_DEVICES_SET_U,
101 		.rst_clr_reg = RST_DEVICES_CLR_U,
102 	},
103 	[3] = {
104 		.enb_reg = CLK_OUT_ENB_V,
105 		.enb_set_reg = CLK_OUT_ENB_SET_V,
106 		.enb_clr_reg = CLK_OUT_ENB_CLR_V,
107 		.rst_reg = RST_DEVICES_V,
108 		.rst_set_reg = RST_DEVICES_SET_V,
109 		.rst_clr_reg = RST_DEVICES_CLR_V,
110 	},
111 	[4] = {
112 		.enb_reg = CLK_OUT_ENB_W,
113 		.enb_set_reg = CLK_OUT_ENB_SET_W,
114 		.enb_clr_reg = CLK_OUT_ENB_CLR_W,
115 		.rst_reg = RST_DEVICES_W,
116 		.rst_set_reg = RST_DEVICES_SET_W,
117 		.rst_clr_reg = RST_DEVICES_CLR_W,
118 	},
119 	[5] = {
120 		.enb_reg = CLK_OUT_ENB_X,
121 		.enb_set_reg = CLK_OUT_ENB_SET_X,
122 		.enb_clr_reg = CLK_OUT_ENB_CLR_X,
123 		.rst_reg = RST_DEVICES_X,
124 		.rst_set_reg = RST_DEVICES_SET_X,
125 		.rst_clr_reg = RST_DEVICES_CLR_X,
126 	},
127 	[6] = {
128 		.enb_reg = CLK_OUT_ENB_Y,
129 		.enb_set_reg = CLK_OUT_ENB_SET_Y,
130 		.enb_clr_reg = CLK_OUT_ENB_CLR_Y,
131 		.rst_reg = RST_DEVICES_Y,
132 		.rst_set_reg = RST_DEVICES_SET_Y,
133 		.rst_clr_reg = RST_DEVICES_CLR_Y,
134 	},
135 };
136 
137 static void __iomem *clk_base;
138 
139 static int tegra_clk_rst_assert(struct reset_controller_dev *rcdev,
140 		unsigned long id)
141 {
142 	/*
143 	 * If peripheral is on the APB bus then we must read the APB bus to
144 	 * flush the write operation in apb bus. This will avoid peripheral
145 	 * access after disabling clock. Since the reset driver has no
146 	 * knowledge of which reset IDs represent which devices, simply do
147 	 * this all the time.
148 	 */
149 	tegra_read_chipid();
150 
151 	if (id < periph_banks * 32) {
152 		writel_relaxed(BIT(id % 32),
153 			       clk_base + periph_regs[id / 32].rst_set_reg);
154 		return 0;
155 	} else if (id < periph_banks * 32 + num_special_reset) {
156 		return special_reset_assert(id);
157 	}
158 
159 	return -EINVAL;
160 }
161 
162 static int tegra_clk_rst_deassert(struct reset_controller_dev *rcdev,
163 		unsigned long id)
164 {
165 	if (id < periph_banks * 32) {
166 		writel_relaxed(BIT(id % 32),
167 			       clk_base + periph_regs[id / 32].rst_clr_reg);
168 		return 0;
169 	} else if (id < periph_banks * 32 + num_special_reset) {
170 		return special_reset_deassert(id);
171 	}
172 
173 	return -EINVAL;
174 }
175 
176 static int tegra_clk_rst_reset(struct reset_controller_dev *rcdev,
177 		unsigned long id)
178 {
179 	int err;
180 
181 	err = tegra_clk_rst_assert(rcdev, id);
182 	if (err)
183 		return err;
184 
185 	udelay(1);
186 
187 	return tegra_clk_rst_deassert(rcdev, id);
188 }
189 
190 const struct tegra_clk_periph_regs *get_reg_bank(int clkid)
191 {
192 	int reg_bank = clkid / 32;
193 
194 	if (reg_bank < periph_banks)
195 		return &periph_regs[reg_bank];
196 	else {
197 		WARN_ON(1);
198 		return NULL;
199 	}
200 }
201 
202 struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
203 {
204 	clk_base = regs;
205 
206 	if (WARN_ON(banks > ARRAY_SIZE(periph_regs)))
207 		return NULL;
208 
209 	periph_clk_enb_refcnt = kcalloc(32 * banks,
210 					sizeof(*periph_clk_enb_refcnt),
211 					GFP_KERNEL);
212 	if (!periph_clk_enb_refcnt)
213 		return NULL;
214 
215 	periph_banks = banks;
216 
217 	clks = kcalloc(num, sizeof(struct clk *), GFP_KERNEL);
218 	if (!clks)
219 		kfree(periph_clk_enb_refcnt);
220 
221 	clk_num = num;
222 
223 	return clks;
224 }
225 
226 void __init tegra_init_dup_clks(struct tegra_clk_duplicate *dup_list,
227 				struct clk *clks[], int clk_max)
228 {
229 	struct clk *clk;
230 
231 	for (; dup_list->clk_id < clk_max; dup_list++) {
232 		clk = clks[dup_list->clk_id];
233 		dup_list->lookup.clk = clk;
234 		clkdev_add(&dup_list->lookup);
235 	}
236 }
237 
238 void __init tegra_init_from_table(struct tegra_clk_init_table *tbl,
239 				  struct clk *clks[], int clk_max)
240 {
241 	struct clk *clk;
242 
243 	for (; tbl->clk_id < clk_max; tbl++) {
244 		clk = clks[tbl->clk_id];
245 		if (IS_ERR_OR_NULL(clk)) {
246 			pr_err("%s: invalid entry %ld in clks array for id %d\n",
247 			       __func__, PTR_ERR(clk), tbl->clk_id);
248 			WARN_ON(1);
249 
250 			continue;
251 		}
252 
253 		if (tbl->parent_id < clk_max) {
254 			struct clk *parent = clks[tbl->parent_id];
255 			if (clk_set_parent(clk, parent)) {
256 				pr_err("%s: Failed to set parent %s of %s\n",
257 				       __func__, __clk_get_name(parent),
258 				       __clk_get_name(clk));
259 				WARN_ON(1);
260 			}
261 		}
262 
263 		if (tbl->rate)
264 			if (clk_set_rate(clk, tbl->rate)) {
265 				pr_err("%s: Failed to set rate %lu of %s\n",
266 				       __func__, tbl->rate,
267 				       __clk_get_name(clk));
268 				WARN_ON(1);
269 			}
270 
271 		if (tbl->state)
272 			if (clk_prepare_enable(clk)) {
273 				pr_err("%s: Failed to enable %s\n", __func__,
274 				       __clk_get_name(clk));
275 				WARN_ON(1);
276 			}
277 	}
278 }
279 
280 static const struct reset_control_ops rst_ops = {
281 	.assert = tegra_clk_rst_assert,
282 	.deassert = tegra_clk_rst_deassert,
283 	.reset = tegra_clk_rst_reset,
284 };
285 
286 static struct reset_controller_dev rst_ctlr = {
287 	.ops = &rst_ops,
288 	.owner = THIS_MODULE,
289 	.of_reset_n_cells = 1,
290 };
291 
292 void __init tegra_add_of_provider(struct device_node *np,
293 				  void *clk_src_onecell_get)
294 {
295 	int i;
296 
297 	for (i = 0; i < clk_num; i++) {
298 		if (IS_ERR(clks[i])) {
299 			pr_err
300 			    ("Tegra clk %d: register failed with %ld\n",
301 			     i, PTR_ERR(clks[i]));
302 		}
303 		if (!clks[i])
304 			clks[i] = ERR_PTR(-EINVAL);
305 	}
306 
307 	clk_data.clks = clks;
308 	clk_data.clk_num = clk_num;
309 	of_clk_add_provider(np, clk_src_onecell_get, &clk_data);
310 
311 	rst_ctlr.of_node = np;
312 	rst_ctlr.nr_resets = periph_banks * 32 + num_special_reset;
313 	reset_controller_register(&rst_ctlr);
314 }
315 
316 void __init tegra_init_special_resets(unsigned int num,
317 				      int (*assert)(unsigned long),
318 				      int (*deassert)(unsigned long))
319 {
320 	num_special_reset = num;
321 	special_reset_assert = assert;
322 	special_reset_deassert = deassert;
323 }
324 
325 void __init tegra_register_devclks(struct tegra_devclk *dev_clks, int num)
326 {
327 	int i;
328 
329 	for (i = 0; i < num; i++, dev_clks++)
330 		clk_register_clkdev(clks[dev_clks->dt_id], dev_clks->con_id,
331 				dev_clks->dev_id);
332 
333 	for (i = 0; i < clk_num; i++) {
334 		if (!IS_ERR_OR_NULL(clks[i]))
335 			clk_register_clkdev(clks[i], __clk_get_name(clks[i]),
336 				"tegra-clk-debug");
337 	}
338 }
339 
340 struct clk ** __init tegra_lookup_dt_id(int clk_id,
341 					struct tegra_clk *tegra_clk)
342 {
343 	if (tegra_clk[clk_id].present)
344 		return &clks[tegra_clk[clk_id].dt_id];
345 	else
346 		return NULL;
347 }
348 
349 tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
350 
351 static int __init tegra_clocks_apply_init_table(void)
352 {
353 	if (!tegra_clk_apply_init_table)
354 		return 0;
355 
356 	tegra_clk_apply_init_table();
357 
358 	return 0;
359 }
360 arch_initcall(tegra_clocks_apply_init_table);
361