xref: /openbmc/linux/drivers/clk/tegra/clk.c (revision 239480ab)
1 /*
2  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
15  */
16 
17 #include <linux/clkdev.h>
18 #include <linux/clk.h>
19 #include <linux/clk-provider.h>
20 #include <linux/delay.h>
21 #include <linux/of.h>
22 #include <linux/clk/tegra.h>
23 #include <linux/reset-controller.h>
24 
25 #include <soc/tegra/fuse.h>
26 
27 #include "clk.h"
28 
29 #define CLK_OUT_ENB_L			0x010
30 #define CLK_OUT_ENB_H			0x014
31 #define CLK_OUT_ENB_U			0x018
32 #define CLK_OUT_ENB_V			0x360
33 #define CLK_OUT_ENB_W			0x364
34 #define CLK_OUT_ENB_X			0x280
35 #define CLK_OUT_ENB_Y			0x298
36 #define CLK_OUT_ENB_SET_L		0x320
37 #define CLK_OUT_ENB_CLR_L		0x324
38 #define CLK_OUT_ENB_SET_H		0x328
39 #define CLK_OUT_ENB_CLR_H		0x32c
40 #define CLK_OUT_ENB_SET_U		0x330
41 #define CLK_OUT_ENB_CLR_U		0x334
42 #define CLK_OUT_ENB_SET_V		0x440
43 #define CLK_OUT_ENB_CLR_V		0x444
44 #define CLK_OUT_ENB_SET_W		0x448
45 #define CLK_OUT_ENB_CLR_W		0x44c
46 #define CLK_OUT_ENB_SET_X		0x284
47 #define CLK_OUT_ENB_CLR_X		0x288
48 #define CLK_OUT_ENB_SET_Y		0x29c
49 #define CLK_OUT_ENB_CLR_Y		0x2a0
50 
51 #define RST_DEVICES_L			0x004
52 #define RST_DEVICES_H			0x008
53 #define RST_DEVICES_U			0x00C
54 #define RST_DEVICES_V			0x358
55 #define RST_DEVICES_W			0x35C
56 #define RST_DEVICES_X			0x28C
57 #define RST_DEVICES_Y			0x2a4
58 #define RST_DEVICES_SET_L		0x300
59 #define RST_DEVICES_CLR_L		0x304
60 #define RST_DEVICES_SET_H		0x308
61 #define RST_DEVICES_CLR_H		0x30c
62 #define RST_DEVICES_SET_U		0x310
63 #define RST_DEVICES_CLR_U		0x314
64 #define RST_DEVICES_SET_V		0x430
65 #define RST_DEVICES_CLR_V		0x434
66 #define RST_DEVICES_SET_W		0x438
67 #define RST_DEVICES_CLR_W		0x43c
68 #define RST_DEVICES_SET_X		0x290
69 #define RST_DEVICES_CLR_X		0x294
70 #define RST_DEVICES_SET_Y		0x2a8
71 #define RST_DEVICES_CLR_Y		0x2ac
72 
73 /* Global data of Tegra CPU CAR ops */
74 static struct tegra_cpu_car_ops dummy_car_ops;
75 struct tegra_cpu_car_ops *tegra_cpu_car_ops = &dummy_car_ops;
76 
77 int *periph_clk_enb_refcnt;
78 static int periph_banks;
79 static struct clk **clks;
80 static int clk_num;
81 static struct clk_onecell_data clk_data;
82 
83 /* Handlers for SoC-specific reset lines */
84 static int (*special_reset_assert)(unsigned long);
85 static int (*special_reset_deassert)(unsigned long);
86 static unsigned int num_special_reset;
87 
88 static const struct tegra_clk_periph_regs periph_regs[] = {
89 	[0] = {
90 		.enb_reg = CLK_OUT_ENB_L,
91 		.enb_set_reg = CLK_OUT_ENB_SET_L,
92 		.enb_clr_reg = CLK_OUT_ENB_CLR_L,
93 		.rst_reg = RST_DEVICES_L,
94 		.rst_set_reg = RST_DEVICES_SET_L,
95 		.rst_clr_reg = RST_DEVICES_CLR_L,
96 	},
97 	[1] = {
98 		.enb_reg = CLK_OUT_ENB_H,
99 		.enb_set_reg = CLK_OUT_ENB_SET_H,
100 		.enb_clr_reg = CLK_OUT_ENB_CLR_H,
101 		.rst_reg = RST_DEVICES_H,
102 		.rst_set_reg = RST_DEVICES_SET_H,
103 		.rst_clr_reg = RST_DEVICES_CLR_H,
104 	},
105 	[2] = {
106 		.enb_reg = CLK_OUT_ENB_U,
107 		.enb_set_reg = CLK_OUT_ENB_SET_U,
108 		.enb_clr_reg = CLK_OUT_ENB_CLR_U,
109 		.rst_reg = RST_DEVICES_U,
110 		.rst_set_reg = RST_DEVICES_SET_U,
111 		.rst_clr_reg = RST_DEVICES_CLR_U,
112 	},
113 	[3] = {
114 		.enb_reg = CLK_OUT_ENB_V,
115 		.enb_set_reg = CLK_OUT_ENB_SET_V,
116 		.enb_clr_reg = CLK_OUT_ENB_CLR_V,
117 		.rst_reg = RST_DEVICES_V,
118 		.rst_set_reg = RST_DEVICES_SET_V,
119 		.rst_clr_reg = RST_DEVICES_CLR_V,
120 	},
121 	[4] = {
122 		.enb_reg = CLK_OUT_ENB_W,
123 		.enb_set_reg = CLK_OUT_ENB_SET_W,
124 		.enb_clr_reg = CLK_OUT_ENB_CLR_W,
125 		.rst_reg = RST_DEVICES_W,
126 		.rst_set_reg = RST_DEVICES_SET_W,
127 		.rst_clr_reg = RST_DEVICES_CLR_W,
128 	},
129 	[5] = {
130 		.enb_reg = CLK_OUT_ENB_X,
131 		.enb_set_reg = CLK_OUT_ENB_SET_X,
132 		.enb_clr_reg = CLK_OUT_ENB_CLR_X,
133 		.rst_reg = RST_DEVICES_X,
134 		.rst_set_reg = RST_DEVICES_SET_X,
135 		.rst_clr_reg = RST_DEVICES_CLR_X,
136 	},
137 	[6] = {
138 		.enb_reg = CLK_OUT_ENB_Y,
139 		.enb_set_reg = CLK_OUT_ENB_SET_Y,
140 		.enb_clr_reg = CLK_OUT_ENB_CLR_Y,
141 		.rst_reg = RST_DEVICES_Y,
142 		.rst_set_reg = RST_DEVICES_SET_Y,
143 		.rst_clr_reg = RST_DEVICES_CLR_Y,
144 	},
145 };
146 
147 static void __iomem *clk_base;
148 
149 static int tegra_clk_rst_assert(struct reset_controller_dev *rcdev,
150 		unsigned long id)
151 {
152 	/*
153 	 * If peripheral is on the APB bus then we must read the APB bus to
154 	 * flush the write operation in apb bus. This will avoid peripheral
155 	 * access after disabling clock. Since the reset driver has no
156 	 * knowledge of which reset IDs represent which devices, simply do
157 	 * this all the time.
158 	 */
159 	tegra_read_chipid();
160 
161 	if (id < periph_banks * 32) {
162 		writel_relaxed(BIT(id % 32),
163 			       clk_base + periph_regs[id / 32].rst_set_reg);
164 		return 0;
165 	} else if (id < periph_banks * 32 + num_special_reset) {
166 		return special_reset_assert(id);
167 	}
168 
169 	return -EINVAL;
170 }
171 
172 static int tegra_clk_rst_deassert(struct reset_controller_dev *rcdev,
173 		unsigned long id)
174 {
175 	if (id < periph_banks * 32) {
176 		writel_relaxed(BIT(id % 32),
177 			       clk_base + periph_regs[id / 32].rst_clr_reg);
178 		return 0;
179 	} else if (id < periph_banks * 32 + num_special_reset) {
180 		return special_reset_deassert(id);
181 	}
182 
183 	return -EINVAL;
184 }
185 
186 static int tegra_clk_rst_reset(struct reset_controller_dev *rcdev,
187 		unsigned long id)
188 {
189 	int err;
190 
191 	err = tegra_clk_rst_assert(rcdev, id);
192 	if (err)
193 		return err;
194 
195 	udelay(1);
196 
197 	return tegra_clk_rst_deassert(rcdev, id);
198 }
199 
200 const struct tegra_clk_periph_regs *get_reg_bank(int clkid)
201 {
202 	int reg_bank = clkid / 32;
203 
204 	if (reg_bank < periph_banks)
205 		return &periph_regs[reg_bank];
206 	else {
207 		WARN_ON(1);
208 		return NULL;
209 	}
210 }
211 
212 struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
213 {
214 	clk_base = regs;
215 
216 	if (WARN_ON(banks > ARRAY_SIZE(periph_regs)))
217 		return NULL;
218 
219 	periph_clk_enb_refcnt = kzalloc(32 * banks *
220 				sizeof(*periph_clk_enb_refcnt), GFP_KERNEL);
221 	if (!periph_clk_enb_refcnt)
222 		return NULL;
223 
224 	periph_banks = banks;
225 
226 	clks = kzalloc(num * sizeof(struct clk *), GFP_KERNEL);
227 	if (!clks)
228 		kfree(periph_clk_enb_refcnt);
229 
230 	clk_num = num;
231 
232 	return clks;
233 }
234 
235 void __init tegra_init_dup_clks(struct tegra_clk_duplicate *dup_list,
236 				struct clk *clks[], int clk_max)
237 {
238 	struct clk *clk;
239 
240 	for (; dup_list->clk_id < clk_max; dup_list++) {
241 		clk = clks[dup_list->clk_id];
242 		dup_list->lookup.clk = clk;
243 		clkdev_add(&dup_list->lookup);
244 	}
245 }
246 
247 void __init tegra_init_from_table(struct tegra_clk_init_table *tbl,
248 				  struct clk *clks[], int clk_max)
249 {
250 	struct clk *clk;
251 
252 	for (; tbl->clk_id < clk_max; tbl++) {
253 		clk = clks[tbl->clk_id];
254 		if (IS_ERR_OR_NULL(clk)) {
255 			pr_err("%s: invalid entry %ld in clks array for id %d\n",
256 			       __func__, PTR_ERR(clk), tbl->clk_id);
257 			WARN_ON(1);
258 
259 			continue;
260 		}
261 
262 		if (tbl->parent_id < clk_max) {
263 			struct clk *parent = clks[tbl->parent_id];
264 			if (clk_set_parent(clk, parent)) {
265 				pr_err("%s: Failed to set parent %s of %s\n",
266 				       __func__, __clk_get_name(parent),
267 				       __clk_get_name(clk));
268 				WARN_ON(1);
269 			}
270 		}
271 
272 		if (tbl->rate)
273 			if (clk_set_rate(clk, tbl->rate)) {
274 				pr_err("%s: Failed to set rate %lu of %s\n",
275 				       __func__, tbl->rate,
276 				       __clk_get_name(clk));
277 				WARN_ON(1);
278 			}
279 
280 		if (tbl->state)
281 			if (clk_prepare_enable(clk)) {
282 				pr_err("%s: Failed to enable %s\n", __func__,
283 				       __clk_get_name(clk));
284 				WARN_ON(1);
285 			}
286 	}
287 }
288 
289 static const struct reset_control_ops rst_ops = {
290 	.assert = tegra_clk_rst_assert,
291 	.deassert = tegra_clk_rst_deassert,
292 	.reset = tegra_clk_rst_reset,
293 };
294 
295 static struct reset_controller_dev rst_ctlr = {
296 	.ops = &rst_ops,
297 	.owner = THIS_MODULE,
298 	.of_reset_n_cells = 1,
299 };
300 
301 void __init tegra_add_of_provider(struct device_node *np)
302 {
303 	int i;
304 
305 	for (i = 0; i < clk_num; i++) {
306 		if (IS_ERR(clks[i])) {
307 			pr_err
308 			    ("Tegra clk %d: register failed with %ld\n",
309 			     i, PTR_ERR(clks[i]));
310 		}
311 		if (!clks[i])
312 			clks[i] = ERR_PTR(-EINVAL);
313 	}
314 
315 	clk_data.clks = clks;
316 	clk_data.clk_num = clk_num;
317 	of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
318 
319 	rst_ctlr.of_node = np;
320 	rst_ctlr.nr_resets = periph_banks * 32 + num_special_reset;
321 	reset_controller_register(&rst_ctlr);
322 }
323 
324 void __init tegra_init_special_resets(unsigned int num,
325 				      int (*assert)(unsigned long),
326 				      int (*deassert)(unsigned long))
327 {
328 	num_special_reset = num;
329 	special_reset_assert = assert;
330 	special_reset_deassert = deassert;
331 }
332 
333 void __init tegra_register_devclks(struct tegra_devclk *dev_clks, int num)
334 {
335 	int i;
336 
337 	for (i = 0; i < num; i++, dev_clks++)
338 		clk_register_clkdev(clks[dev_clks->dt_id], dev_clks->con_id,
339 				dev_clks->dev_id);
340 
341 	for (i = 0; i < clk_num; i++) {
342 		if (!IS_ERR_OR_NULL(clks[i]))
343 			clk_register_clkdev(clks[i], __clk_get_name(clks[i]),
344 				"tegra-clk-debug");
345 	}
346 }
347 
348 struct clk ** __init tegra_lookup_dt_id(int clk_id,
349 					struct tegra_clk *tegra_clk)
350 {
351 	if (tegra_clk[clk_id].present)
352 		return &clks[tegra_clk[clk_id].dt_id];
353 	else
354 		return NULL;
355 }
356 
357 tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
358 
359 static int __init tegra_clocks_apply_init_table(void)
360 {
361 	if (!tegra_clk_apply_init_table)
362 		return 0;
363 
364 	tegra_clk_apply_init_table();
365 
366 	return 0;
367 }
368 arch_initcall(tegra_clocks_apply_init_table);
369