xref: /openbmc/linux/drivers/clk/tegra/clk.c (revision 9cfc5c90)
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/of.h>
21 #include <linux/clk/tegra.h>
22 #include <linux/reset-controller.h>
23 
24 #include <soc/tegra/fuse.h>
25 
26 #include "clk.h"
27 
28 #define CLK_OUT_ENB_L			0x010
29 #define CLK_OUT_ENB_H			0x014
30 #define CLK_OUT_ENB_U			0x018
31 #define CLK_OUT_ENB_V			0x360
32 #define CLK_OUT_ENB_W			0x364
33 #define CLK_OUT_ENB_X			0x280
34 #define CLK_OUT_ENB_Y			0x298
35 #define CLK_OUT_ENB_SET_L		0x320
36 #define CLK_OUT_ENB_CLR_L		0x324
37 #define CLK_OUT_ENB_SET_H		0x328
38 #define CLK_OUT_ENB_CLR_H		0x32c
39 #define CLK_OUT_ENB_SET_U		0x330
40 #define CLK_OUT_ENB_CLR_U		0x334
41 #define CLK_OUT_ENB_SET_V		0x440
42 #define CLK_OUT_ENB_CLR_V		0x444
43 #define CLK_OUT_ENB_SET_W		0x448
44 #define CLK_OUT_ENB_CLR_W		0x44c
45 #define CLK_OUT_ENB_SET_X		0x284
46 #define CLK_OUT_ENB_CLR_X		0x288
47 #define CLK_OUT_ENB_SET_Y		0x29c
48 #define CLK_OUT_ENB_CLR_Y		0x2a0
49 
50 #define RST_DEVICES_L			0x004
51 #define RST_DEVICES_H			0x008
52 #define RST_DEVICES_U			0x00C
53 #define RST_DEVICES_V			0x358
54 #define RST_DEVICES_W			0x35C
55 #define RST_DEVICES_X			0x28C
56 #define RST_DEVICES_Y			0x2a4
57 #define RST_DEVICES_SET_L		0x300
58 #define RST_DEVICES_CLR_L		0x304
59 #define RST_DEVICES_SET_H		0x308
60 #define RST_DEVICES_CLR_H		0x30c
61 #define RST_DEVICES_SET_U		0x310
62 #define RST_DEVICES_CLR_U		0x314
63 #define RST_DEVICES_SET_V		0x430
64 #define RST_DEVICES_CLR_V		0x434
65 #define RST_DEVICES_SET_W		0x438
66 #define RST_DEVICES_CLR_W		0x43c
67 #define RST_DEVICES_SET_X		0x290
68 #define RST_DEVICES_CLR_X		0x294
69 #define RST_DEVICES_SET_Y		0x2a8
70 #define RST_DEVICES_CLR_Y		0x2ac
71 
72 /* Global data of Tegra CPU CAR ops */
73 static struct tegra_cpu_car_ops dummy_car_ops;
74 struct tegra_cpu_car_ops *tegra_cpu_car_ops = &dummy_car_ops;
75 
76 int *periph_clk_enb_refcnt;
77 static int periph_banks;
78 static struct clk **clks;
79 static int clk_num;
80 static struct clk_onecell_data clk_data;
81 
82 /* Handlers for SoC-specific reset lines */
83 static int (*special_reset_assert)(unsigned long);
84 static int (*special_reset_deassert)(unsigned long);
85 static unsigned int num_special_reset;
86 
87 static struct tegra_clk_periph_regs periph_regs[] = {
88 	[0] = {
89 		.enb_reg = CLK_OUT_ENB_L,
90 		.enb_set_reg = CLK_OUT_ENB_SET_L,
91 		.enb_clr_reg = CLK_OUT_ENB_CLR_L,
92 		.rst_reg = RST_DEVICES_L,
93 		.rst_set_reg = RST_DEVICES_SET_L,
94 		.rst_clr_reg = RST_DEVICES_CLR_L,
95 	},
96 	[1] = {
97 		.enb_reg = CLK_OUT_ENB_H,
98 		.enb_set_reg = CLK_OUT_ENB_SET_H,
99 		.enb_clr_reg = CLK_OUT_ENB_CLR_H,
100 		.rst_reg = RST_DEVICES_H,
101 		.rst_set_reg = RST_DEVICES_SET_H,
102 		.rst_clr_reg = RST_DEVICES_CLR_H,
103 	},
104 	[2] = {
105 		.enb_reg = CLK_OUT_ENB_U,
106 		.enb_set_reg = CLK_OUT_ENB_SET_U,
107 		.enb_clr_reg = CLK_OUT_ENB_CLR_U,
108 		.rst_reg = RST_DEVICES_U,
109 		.rst_set_reg = RST_DEVICES_SET_U,
110 		.rst_clr_reg = RST_DEVICES_CLR_U,
111 	},
112 	[3] = {
113 		.enb_reg = CLK_OUT_ENB_V,
114 		.enb_set_reg = CLK_OUT_ENB_SET_V,
115 		.enb_clr_reg = CLK_OUT_ENB_CLR_V,
116 		.rst_reg = RST_DEVICES_V,
117 		.rst_set_reg = RST_DEVICES_SET_V,
118 		.rst_clr_reg = RST_DEVICES_CLR_V,
119 	},
120 	[4] = {
121 		.enb_reg = CLK_OUT_ENB_W,
122 		.enb_set_reg = CLK_OUT_ENB_SET_W,
123 		.enb_clr_reg = CLK_OUT_ENB_CLR_W,
124 		.rst_reg = RST_DEVICES_W,
125 		.rst_set_reg = RST_DEVICES_SET_W,
126 		.rst_clr_reg = RST_DEVICES_CLR_W,
127 	},
128 	[5] = {
129 		.enb_reg = CLK_OUT_ENB_X,
130 		.enb_set_reg = CLK_OUT_ENB_SET_X,
131 		.enb_clr_reg = CLK_OUT_ENB_CLR_X,
132 		.rst_reg = RST_DEVICES_X,
133 		.rst_set_reg = RST_DEVICES_SET_X,
134 		.rst_clr_reg = RST_DEVICES_CLR_X,
135 	},
136 	[6] = {
137 		.enb_reg = CLK_OUT_ENB_Y,
138 		.enb_set_reg = CLK_OUT_ENB_SET_Y,
139 		.enb_clr_reg = CLK_OUT_ENB_CLR_Y,
140 		.rst_reg = RST_DEVICES_Y,
141 		.rst_set_reg = RST_DEVICES_SET_Y,
142 		.rst_clr_reg = RST_DEVICES_CLR_Y,
143 	},
144 };
145 
146 static void __iomem *clk_base;
147 
148 static int tegra_clk_rst_assert(struct reset_controller_dev *rcdev,
149 		unsigned long id)
150 {
151 	/*
152 	 * If peripheral is on the APB bus then we must read the APB bus to
153 	 * flush the write operation in apb bus. This will avoid peripheral
154 	 * access after disabling clock. Since the reset driver has no
155 	 * knowledge of which reset IDs represent which devices, simply do
156 	 * this all the time.
157 	 */
158 	tegra_read_chipid();
159 
160 	if (id < periph_banks * 32) {
161 		writel_relaxed(BIT(id % 32),
162 			       clk_base + periph_regs[id / 32].rst_set_reg);
163 		return 0;
164 	} else if (id < periph_banks * 32 + num_special_reset) {
165 		return special_reset_assert(id);
166 	}
167 
168 	return -EINVAL;
169 }
170 
171 static int tegra_clk_rst_deassert(struct reset_controller_dev *rcdev,
172 		unsigned long id)
173 {
174 	if (id < periph_banks * 32) {
175 		writel_relaxed(BIT(id % 32),
176 			       clk_base + periph_regs[id / 32].rst_clr_reg);
177 		return 0;
178 	} else if (id < periph_banks * 32 + num_special_reset) {
179 		return special_reset_deassert(id);
180 	}
181 
182 	return -EINVAL;
183 }
184 
185 struct tegra_clk_periph_regs *get_reg_bank(int clkid)
186 {
187 	int reg_bank = clkid / 32;
188 
189 	if (reg_bank < periph_banks)
190 		return &periph_regs[reg_bank];
191 	else {
192 		WARN_ON(1);
193 		return NULL;
194 	}
195 }
196 
197 struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
198 {
199 	clk_base = regs;
200 
201 	if (WARN_ON(banks > ARRAY_SIZE(periph_regs)))
202 		return NULL;
203 
204 	periph_clk_enb_refcnt = kzalloc(32 * banks *
205 				sizeof(*periph_clk_enb_refcnt), GFP_KERNEL);
206 	if (!periph_clk_enb_refcnt)
207 		return NULL;
208 
209 	periph_banks = banks;
210 
211 	clks = kzalloc(num * sizeof(struct clk *), GFP_KERNEL);
212 	if (!clks)
213 		kfree(periph_clk_enb_refcnt);
214 
215 	clk_num = num;
216 
217 	return clks;
218 }
219 
220 void __init tegra_init_dup_clks(struct tegra_clk_duplicate *dup_list,
221 				struct clk *clks[], int clk_max)
222 {
223 	struct clk *clk;
224 
225 	for (; dup_list->clk_id < clk_max; dup_list++) {
226 		clk = clks[dup_list->clk_id];
227 		dup_list->lookup.clk = clk;
228 		clkdev_add(&dup_list->lookup);
229 	}
230 }
231 
232 void __init tegra_init_from_table(struct tegra_clk_init_table *tbl,
233 				  struct clk *clks[], int clk_max)
234 {
235 	struct clk *clk;
236 
237 	for (; tbl->clk_id < clk_max; tbl++) {
238 		clk = clks[tbl->clk_id];
239 		if (IS_ERR_OR_NULL(clk)) {
240 			pr_err("%s: invalid entry %ld in clks array for id %d\n",
241 			       __func__, PTR_ERR(clk), tbl->clk_id);
242 			WARN_ON(1);
243 
244 			continue;
245 		}
246 
247 		if (tbl->parent_id < clk_max) {
248 			struct clk *parent = clks[tbl->parent_id];
249 			if (clk_set_parent(clk, parent)) {
250 				pr_err("%s: Failed to set parent %s of %s\n",
251 				       __func__, __clk_get_name(parent),
252 				       __clk_get_name(clk));
253 				WARN_ON(1);
254 			}
255 		}
256 
257 		if (tbl->rate)
258 			if (clk_set_rate(clk, tbl->rate)) {
259 				pr_err("%s: Failed to set rate %lu of %s\n",
260 				       __func__, tbl->rate,
261 				       __clk_get_name(clk));
262 				WARN_ON(1);
263 			}
264 
265 		if (tbl->state)
266 			if (clk_prepare_enable(clk)) {
267 				pr_err("%s: Failed to enable %s\n", __func__,
268 				       __clk_get_name(clk));
269 				WARN_ON(1);
270 			}
271 	}
272 }
273 
274 static struct reset_control_ops rst_ops = {
275 	.assert = tegra_clk_rst_assert,
276 	.deassert = tegra_clk_rst_deassert,
277 };
278 
279 static struct reset_controller_dev rst_ctlr = {
280 	.ops = &rst_ops,
281 	.owner = THIS_MODULE,
282 	.of_reset_n_cells = 1,
283 };
284 
285 void __init tegra_add_of_provider(struct device_node *np)
286 {
287 	int i;
288 
289 	for (i = 0; i < clk_num; i++) {
290 		if (IS_ERR(clks[i])) {
291 			pr_err
292 			    ("Tegra clk %d: register failed with %ld\n",
293 			     i, PTR_ERR(clks[i]));
294 		}
295 		if (!clks[i])
296 			clks[i] = ERR_PTR(-EINVAL);
297 	}
298 
299 	clk_data.clks = clks;
300 	clk_data.clk_num = clk_num;
301 	of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
302 
303 	rst_ctlr.of_node = np;
304 	rst_ctlr.nr_resets = periph_banks * 32 + num_special_reset;
305 	reset_controller_register(&rst_ctlr);
306 }
307 
308 void __init tegra_init_special_resets(unsigned int num,
309 				      int (*assert)(unsigned long),
310 				      int (*deassert)(unsigned long))
311 {
312 	num_special_reset = num;
313 	special_reset_assert = assert;
314 	special_reset_deassert = deassert;
315 }
316 
317 void __init tegra_register_devclks(struct tegra_devclk *dev_clks, int num)
318 {
319 	int i;
320 
321 	for (i = 0; i < num; i++, dev_clks++)
322 		clk_register_clkdev(clks[dev_clks->dt_id], dev_clks->con_id,
323 				dev_clks->dev_id);
324 
325 	for (i = 0; i < clk_num; i++) {
326 		if (!IS_ERR_OR_NULL(clks[i]))
327 			clk_register_clkdev(clks[i], __clk_get_name(clks[i]),
328 				"tegra-clk-debug");
329 	}
330 }
331 
332 struct clk ** __init tegra_lookup_dt_id(int clk_id,
333 					struct tegra_clk *tegra_clk)
334 {
335 	if (tegra_clk[clk_id].present)
336 		return &clks[tegra_clk[clk_id].dt_id];
337 	else
338 		return NULL;
339 }
340 
341 tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
342 
343 static int __init tegra_clocks_apply_init_table(void)
344 {
345 	if (!tegra_clk_apply_init_table)
346 		return 0;
347 
348 	tegra_clk_apply_init_table();
349 
350 	return 0;
351 }
352 arch_initcall(tegra_clocks_apply_init_table);
353