xref: /openbmc/linux/drivers/clk/tegra/clk.c (revision 5a1ea477)
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/io.h>
22 #include <linux/of.h>
23 #include <linux/clk/tegra.h>
24 #include <linux/reset-controller.h>
25 
26 #include <soc/tegra/fuse.h>
27 
28 #include "clk.h"
29 
30 #define CLK_OUT_ENB_L			0x010
31 #define CLK_OUT_ENB_H			0x014
32 #define CLK_OUT_ENB_U			0x018
33 #define CLK_OUT_ENB_V			0x360
34 #define CLK_OUT_ENB_W			0x364
35 #define CLK_OUT_ENB_X			0x280
36 #define CLK_OUT_ENB_Y			0x298
37 #define CLK_OUT_ENB_SET_L		0x320
38 #define CLK_OUT_ENB_CLR_L		0x324
39 #define CLK_OUT_ENB_SET_H		0x328
40 #define CLK_OUT_ENB_CLR_H		0x32c
41 #define CLK_OUT_ENB_SET_U		0x330
42 #define CLK_OUT_ENB_CLR_U		0x334
43 #define CLK_OUT_ENB_SET_V		0x440
44 #define CLK_OUT_ENB_CLR_V		0x444
45 #define CLK_OUT_ENB_SET_W		0x448
46 #define CLK_OUT_ENB_CLR_W		0x44c
47 #define CLK_OUT_ENB_SET_X		0x284
48 #define CLK_OUT_ENB_CLR_X		0x288
49 #define CLK_OUT_ENB_SET_Y		0x29c
50 #define CLK_OUT_ENB_CLR_Y		0x2a0
51 
52 #define RST_DEVICES_L			0x004
53 #define RST_DEVICES_H			0x008
54 #define RST_DEVICES_U			0x00C
55 #define RST_DEVICES_V			0x358
56 #define RST_DEVICES_W			0x35C
57 #define RST_DEVICES_X			0x28C
58 #define RST_DEVICES_Y			0x2a4
59 #define RST_DEVICES_SET_L		0x300
60 #define RST_DEVICES_CLR_L		0x304
61 #define RST_DEVICES_SET_H		0x308
62 #define RST_DEVICES_CLR_H		0x30c
63 #define RST_DEVICES_SET_U		0x310
64 #define RST_DEVICES_CLR_U		0x314
65 #define RST_DEVICES_SET_V		0x430
66 #define RST_DEVICES_CLR_V		0x434
67 #define RST_DEVICES_SET_W		0x438
68 #define RST_DEVICES_CLR_W		0x43c
69 #define RST_DEVICES_SET_X		0x290
70 #define RST_DEVICES_CLR_X		0x294
71 #define RST_DEVICES_SET_Y		0x2a8
72 #define RST_DEVICES_CLR_Y		0x2ac
73 
74 /* Global data of Tegra CPU CAR ops */
75 static struct tegra_cpu_car_ops dummy_car_ops;
76 struct tegra_cpu_car_ops *tegra_cpu_car_ops = &dummy_car_ops;
77 
78 int *periph_clk_enb_refcnt;
79 static int periph_banks;
80 static struct clk **clks;
81 static int clk_num;
82 static struct clk_onecell_data clk_data;
83 
84 /* Handlers for SoC-specific reset lines */
85 static int (*special_reset_assert)(unsigned long);
86 static int (*special_reset_deassert)(unsigned long);
87 static unsigned int num_special_reset;
88 
89 static const struct tegra_clk_periph_regs periph_regs[] = {
90 	[0] = {
91 		.enb_reg = CLK_OUT_ENB_L,
92 		.enb_set_reg = CLK_OUT_ENB_SET_L,
93 		.enb_clr_reg = CLK_OUT_ENB_CLR_L,
94 		.rst_reg = RST_DEVICES_L,
95 		.rst_set_reg = RST_DEVICES_SET_L,
96 		.rst_clr_reg = RST_DEVICES_CLR_L,
97 	},
98 	[1] = {
99 		.enb_reg = CLK_OUT_ENB_H,
100 		.enb_set_reg = CLK_OUT_ENB_SET_H,
101 		.enb_clr_reg = CLK_OUT_ENB_CLR_H,
102 		.rst_reg = RST_DEVICES_H,
103 		.rst_set_reg = RST_DEVICES_SET_H,
104 		.rst_clr_reg = RST_DEVICES_CLR_H,
105 	},
106 	[2] = {
107 		.enb_reg = CLK_OUT_ENB_U,
108 		.enb_set_reg = CLK_OUT_ENB_SET_U,
109 		.enb_clr_reg = CLK_OUT_ENB_CLR_U,
110 		.rst_reg = RST_DEVICES_U,
111 		.rst_set_reg = RST_DEVICES_SET_U,
112 		.rst_clr_reg = RST_DEVICES_CLR_U,
113 	},
114 	[3] = {
115 		.enb_reg = CLK_OUT_ENB_V,
116 		.enb_set_reg = CLK_OUT_ENB_SET_V,
117 		.enb_clr_reg = CLK_OUT_ENB_CLR_V,
118 		.rst_reg = RST_DEVICES_V,
119 		.rst_set_reg = RST_DEVICES_SET_V,
120 		.rst_clr_reg = RST_DEVICES_CLR_V,
121 	},
122 	[4] = {
123 		.enb_reg = CLK_OUT_ENB_W,
124 		.enb_set_reg = CLK_OUT_ENB_SET_W,
125 		.enb_clr_reg = CLK_OUT_ENB_CLR_W,
126 		.rst_reg = RST_DEVICES_W,
127 		.rst_set_reg = RST_DEVICES_SET_W,
128 		.rst_clr_reg = RST_DEVICES_CLR_W,
129 	},
130 	[5] = {
131 		.enb_reg = CLK_OUT_ENB_X,
132 		.enb_set_reg = CLK_OUT_ENB_SET_X,
133 		.enb_clr_reg = CLK_OUT_ENB_CLR_X,
134 		.rst_reg = RST_DEVICES_X,
135 		.rst_set_reg = RST_DEVICES_SET_X,
136 		.rst_clr_reg = RST_DEVICES_CLR_X,
137 	},
138 	[6] = {
139 		.enb_reg = CLK_OUT_ENB_Y,
140 		.enb_set_reg = CLK_OUT_ENB_SET_Y,
141 		.enb_clr_reg = CLK_OUT_ENB_CLR_Y,
142 		.rst_reg = RST_DEVICES_Y,
143 		.rst_set_reg = RST_DEVICES_SET_Y,
144 		.rst_clr_reg = RST_DEVICES_CLR_Y,
145 	},
146 };
147 
148 static void __iomem *clk_base;
149 
150 static int tegra_clk_rst_assert(struct reset_controller_dev *rcdev,
151 		unsigned long id)
152 {
153 	/*
154 	 * If peripheral is on the APB bus then we must read the APB bus to
155 	 * flush the write operation in apb bus. This will avoid peripheral
156 	 * access after disabling clock. Since the reset driver has no
157 	 * knowledge of which reset IDs represent which devices, simply do
158 	 * this all the time.
159 	 */
160 	tegra_read_chipid();
161 
162 	if (id < periph_banks * 32) {
163 		writel_relaxed(BIT(id % 32),
164 			       clk_base + periph_regs[id / 32].rst_set_reg);
165 		return 0;
166 	} else if (id < periph_banks * 32 + num_special_reset) {
167 		return special_reset_assert(id);
168 	}
169 
170 	return -EINVAL;
171 }
172 
173 static int tegra_clk_rst_deassert(struct reset_controller_dev *rcdev,
174 		unsigned long id)
175 {
176 	if (id < periph_banks * 32) {
177 		writel_relaxed(BIT(id % 32),
178 			       clk_base + periph_regs[id / 32].rst_clr_reg);
179 		return 0;
180 	} else if (id < periph_banks * 32 + num_special_reset) {
181 		return special_reset_deassert(id);
182 	}
183 
184 	return -EINVAL;
185 }
186 
187 static int tegra_clk_rst_reset(struct reset_controller_dev *rcdev,
188 		unsigned long id)
189 {
190 	int err;
191 
192 	err = tegra_clk_rst_assert(rcdev, id);
193 	if (err)
194 		return err;
195 
196 	udelay(1);
197 
198 	return tegra_clk_rst_deassert(rcdev, id);
199 }
200 
201 const struct tegra_clk_periph_regs *get_reg_bank(int clkid)
202 {
203 	int reg_bank = clkid / 32;
204 
205 	if (reg_bank < periph_banks)
206 		return &periph_regs[reg_bank];
207 	else {
208 		WARN_ON(1);
209 		return NULL;
210 	}
211 }
212 
213 struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
214 {
215 	clk_base = regs;
216 
217 	if (WARN_ON(banks > ARRAY_SIZE(periph_regs)))
218 		return NULL;
219 
220 	periph_clk_enb_refcnt = kcalloc(32 * banks,
221 					sizeof(*periph_clk_enb_refcnt),
222 					GFP_KERNEL);
223 	if (!periph_clk_enb_refcnt)
224 		return NULL;
225 
226 	periph_banks = banks;
227 
228 	clks = kcalloc(num, sizeof(struct clk *), GFP_KERNEL);
229 	if (!clks)
230 		kfree(periph_clk_enb_refcnt);
231 
232 	clk_num = num;
233 
234 	return clks;
235 }
236 
237 void __init tegra_init_dup_clks(struct tegra_clk_duplicate *dup_list,
238 				struct clk *clks[], int clk_max)
239 {
240 	struct clk *clk;
241 
242 	for (; dup_list->clk_id < clk_max; dup_list++) {
243 		clk = clks[dup_list->clk_id];
244 		dup_list->lookup.clk = clk;
245 		clkdev_add(&dup_list->lookup);
246 	}
247 }
248 
249 void __init tegra_init_from_table(struct tegra_clk_init_table *tbl,
250 				  struct clk *clks[], int clk_max)
251 {
252 	struct clk *clk;
253 
254 	for (; tbl->clk_id < clk_max; tbl++) {
255 		clk = clks[tbl->clk_id];
256 		if (IS_ERR_OR_NULL(clk)) {
257 			pr_err("%s: invalid entry %ld in clks array for id %d\n",
258 			       __func__, PTR_ERR(clk), tbl->clk_id);
259 			WARN_ON(1);
260 
261 			continue;
262 		}
263 
264 		if (tbl->parent_id < clk_max) {
265 			struct clk *parent = clks[tbl->parent_id];
266 			if (clk_set_parent(clk, parent)) {
267 				pr_err("%s: Failed to set parent %s of %s\n",
268 				       __func__, __clk_get_name(parent),
269 				       __clk_get_name(clk));
270 				WARN_ON(1);
271 			}
272 		}
273 
274 		if (tbl->rate)
275 			if (clk_set_rate(clk, tbl->rate)) {
276 				pr_err("%s: Failed to set rate %lu of %s\n",
277 				       __func__, tbl->rate,
278 				       __clk_get_name(clk));
279 				WARN_ON(1);
280 			}
281 
282 		if (tbl->state)
283 			if (clk_prepare_enable(clk)) {
284 				pr_err("%s: Failed to enable %s\n", __func__,
285 				       __clk_get_name(clk));
286 				WARN_ON(1);
287 			}
288 	}
289 }
290 
291 static const struct reset_control_ops rst_ops = {
292 	.assert = tegra_clk_rst_assert,
293 	.deassert = tegra_clk_rst_deassert,
294 	.reset = tegra_clk_rst_reset,
295 };
296 
297 static struct reset_controller_dev rst_ctlr = {
298 	.ops = &rst_ops,
299 	.owner = THIS_MODULE,
300 	.of_reset_n_cells = 1,
301 };
302 
303 void __init tegra_add_of_provider(struct device_node *np,
304 				  void *clk_src_onecell_get)
305 {
306 	int i;
307 
308 	for (i = 0; i < clk_num; i++) {
309 		if (IS_ERR(clks[i])) {
310 			pr_err
311 			    ("Tegra clk %d: register failed with %ld\n",
312 			     i, PTR_ERR(clks[i]));
313 		}
314 		if (!clks[i])
315 			clks[i] = ERR_PTR(-EINVAL);
316 	}
317 
318 	clk_data.clks = clks;
319 	clk_data.clk_num = clk_num;
320 	of_clk_add_provider(np, clk_src_onecell_get, &clk_data);
321 
322 	rst_ctlr.of_node = np;
323 	rst_ctlr.nr_resets = periph_banks * 32 + num_special_reset;
324 	reset_controller_register(&rst_ctlr);
325 }
326 
327 void __init tegra_init_special_resets(unsigned int num,
328 				      int (*assert)(unsigned long),
329 				      int (*deassert)(unsigned long))
330 {
331 	num_special_reset = num;
332 	special_reset_assert = assert;
333 	special_reset_deassert = deassert;
334 }
335 
336 void __init tegra_register_devclks(struct tegra_devclk *dev_clks, int num)
337 {
338 	int i;
339 
340 	for (i = 0; i < num; i++, dev_clks++)
341 		clk_register_clkdev(clks[dev_clks->dt_id], dev_clks->con_id,
342 				dev_clks->dev_id);
343 
344 	for (i = 0; i < clk_num; i++) {
345 		if (!IS_ERR_OR_NULL(clks[i]))
346 			clk_register_clkdev(clks[i], __clk_get_name(clks[i]),
347 				"tegra-clk-debug");
348 	}
349 }
350 
351 struct clk ** __init tegra_lookup_dt_id(int clk_id,
352 					struct tegra_clk *tegra_clk)
353 {
354 	if (tegra_clk[clk_id].present)
355 		return &clks[tegra_clk[clk_id].dt_id];
356 	else
357 		return NULL;
358 }
359 
360 tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
361 
362 static int __init tegra_clocks_apply_init_table(void)
363 {
364 	if (!tegra_clk_apply_init_table)
365 		return 0;
366 
367 	tegra_clk_apply_init_table();
368 
369 	return 0;
370 }
371 arch_initcall(tegra_clocks_apply_init_table);
372