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 /* Global data of Tegra CPU CAR ops */
20 static struct tegra_cpu_car_ops dummy_car_ops;
21 struct tegra_cpu_car_ops *tegra_cpu_car_ops = &dummy_car_ops;
22
23 int *periph_clk_enb_refcnt;
24 static int periph_banks;
25 static u32 *periph_state_ctx;
26 static struct clk **clks;
27 static int clk_num;
28 static struct clk_onecell_data clk_data;
29
30 /* Handlers for SoC-specific reset lines */
31 static int (*special_reset_assert)(unsigned long);
32 static int (*special_reset_deassert)(unsigned long);
33 static unsigned int num_special_reset;
34
35 static const struct tegra_clk_periph_regs periph_regs[] = {
36 [0] = {
37 .enb_reg = CLK_OUT_ENB_L,
38 .enb_set_reg = CLK_OUT_ENB_SET_L,
39 .enb_clr_reg = CLK_OUT_ENB_CLR_L,
40 .rst_reg = RST_DEVICES_L,
41 .rst_set_reg = RST_DEVICES_SET_L,
42 .rst_clr_reg = RST_DEVICES_CLR_L,
43 },
44 [1] = {
45 .enb_reg = CLK_OUT_ENB_H,
46 .enb_set_reg = CLK_OUT_ENB_SET_H,
47 .enb_clr_reg = CLK_OUT_ENB_CLR_H,
48 .rst_reg = RST_DEVICES_H,
49 .rst_set_reg = RST_DEVICES_SET_H,
50 .rst_clr_reg = RST_DEVICES_CLR_H,
51 },
52 [2] = {
53 .enb_reg = CLK_OUT_ENB_U,
54 .enb_set_reg = CLK_OUT_ENB_SET_U,
55 .enb_clr_reg = CLK_OUT_ENB_CLR_U,
56 .rst_reg = RST_DEVICES_U,
57 .rst_set_reg = RST_DEVICES_SET_U,
58 .rst_clr_reg = RST_DEVICES_CLR_U,
59 },
60 [3] = {
61 .enb_reg = CLK_OUT_ENB_V,
62 .enb_set_reg = CLK_OUT_ENB_SET_V,
63 .enb_clr_reg = CLK_OUT_ENB_CLR_V,
64 .rst_reg = RST_DEVICES_V,
65 .rst_set_reg = RST_DEVICES_SET_V,
66 .rst_clr_reg = RST_DEVICES_CLR_V,
67 },
68 [4] = {
69 .enb_reg = CLK_OUT_ENB_W,
70 .enb_set_reg = CLK_OUT_ENB_SET_W,
71 .enb_clr_reg = CLK_OUT_ENB_CLR_W,
72 .rst_reg = RST_DEVICES_W,
73 .rst_set_reg = RST_DEVICES_SET_W,
74 .rst_clr_reg = RST_DEVICES_CLR_W,
75 },
76 [5] = {
77 .enb_reg = CLK_OUT_ENB_X,
78 .enb_set_reg = CLK_OUT_ENB_SET_X,
79 .enb_clr_reg = CLK_OUT_ENB_CLR_X,
80 .rst_reg = RST_DEVICES_X,
81 .rst_set_reg = RST_DEVICES_SET_X,
82 .rst_clr_reg = RST_DEVICES_CLR_X,
83 },
84 [6] = {
85 .enb_reg = CLK_OUT_ENB_Y,
86 .enb_set_reg = CLK_OUT_ENB_SET_Y,
87 .enb_clr_reg = CLK_OUT_ENB_CLR_Y,
88 .rst_reg = RST_DEVICES_Y,
89 .rst_set_reg = RST_DEVICES_SET_Y,
90 .rst_clr_reg = RST_DEVICES_CLR_Y,
91 },
92 };
93
94 static void __iomem *clk_base;
95
tegra_clk_rst_assert(struct reset_controller_dev * rcdev,unsigned long id)96 static int tegra_clk_rst_assert(struct reset_controller_dev *rcdev,
97 unsigned long id)
98 {
99 /*
100 * If peripheral is on the APB bus then we must read the APB bus to
101 * flush the write operation in apb bus. This will avoid peripheral
102 * access after disabling clock. Since the reset driver has no
103 * knowledge of which reset IDs represent which devices, simply do
104 * this all the time.
105 */
106 tegra_read_chipid();
107
108 if (id < periph_banks * 32) {
109 writel_relaxed(BIT(id % 32),
110 clk_base + periph_regs[id / 32].rst_set_reg);
111 return 0;
112 } else if (id < periph_banks * 32 + num_special_reset) {
113 return special_reset_assert(id);
114 }
115
116 return -EINVAL;
117 }
118
tegra_clk_rst_deassert(struct reset_controller_dev * rcdev,unsigned long id)119 static int tegra_clk_rst_deassert(struct reset_controller_dev *rcdev,
120 unsigned long id)
121 {
122 if (id < periph_banks * 32) {
123 writel_relaxed(BIT(id % 32),
124 clk_base + periph_regs[id / 32].rst_clr_reg);
125 return 0;
126 } else if (id < periph_banks * 32 + num_special_reset) {
127 return special_reset_deassert(id);
128 }
129
130 return -EINVAL;
131 }
132
tegra_clk_rst_reset(struct reset_controller_dev * rcdev,unsigned long id)133 static int tegra_clk_rst_reset(struct reset_controller_dev *rcdev,
134 unsigned long id)
135 {
136 int err;
137
138 err = tegra_clk_rst_assert(rcdev, id);
139 if (err)
140 return err;
141
142 udelay(1);
143
144 return tegra_clk_rst_deassert(rcdev, id);
145 }
146
get_reg_bank(int clkid)147 const struct tegra_clk_periph_regs *get_reg_bank(int clkid)
148 {
149 int reg_bank = clkid / 32;
150
151 if (reg_bank < periph_banks)
152 return &periph_regs[reg_bank];
153 else {
154 WARN_ON(1);
155 return NULL;
156 }
157 }
158
tegra_clk_set_pllp_out_cpu(bool enable)159 void tegra_clk_set_pllp_out_cpu(bool enable)
160 {
161 u32 val;
162
163 val = readl_relaxed(clk_base + CLK_OUT_ENB_Y);
164 if (enable)
165 val |= CLK_ENB_PLLP_OUT_CPU;
166 else
167 val &= ~CLK_ENB_PLLP_OUT_CPU;
168
169 writel_relaxed(val, clk_base + CLK_OUT_ENB_Y);
170 }
171
tegra_clk_periph_suspend(void)172 void tegra_clk_periph_suspend(void)
173 {
174 unsigned int i, idx;
175
176 idx = 0;
177 for (i = 0; i < periph_banks; i++, idx++)
178 periph_state_ctx[idx] =
179 readl_relaxed(clk_base + periph_regs[i].enb_reg);
180
181 for (i = 0; i < periph_banks; i++, idx++)
182 periph_state_ctx[idx] =
183 readl_relaxed(clk_base + periph_regs[i].rst_reg);
184 }
185
tegra_clk_periph_resume(void)186 void tegra_clk_periph_resume(void)
187 {
188 unsigned int i, idx;
189
190 idx = 0;
191 for (i = 0; i < periph_banks; i++, idx++)
192 writel_relaxed(periph_state_ctx[idx],
193 clk_base + periph_regs[i].enb_reg);
194 /*
195 * All non-boot peripherals will be in reset state on resume.
196 * Wait for 5us of reset propagation delay before de-asserting
197 * the peripherals based on the saved context.
198 */
199 fence_udelay(5, clk_base);
200
201 for (i = 0; i < periph_banks; i++, idx++)
202 writel_relaxed(periph_state_ctx[idx],
203 clk_base + periph_regs[i].rst_reg);
204
205 fence_udelay(2, clk_base);
206 }
207
tegra_clk_periph_ctx_init(int banks)208 static int tegra_clk_periph_ctx_init(int banks)
209 {
210 periph_state_ctx = kcalloc(2 * banks, sizeof(*periph_state_ctx),
211 GFP_KERNEL);
212 if (!periph_state_ctx)
213 return -ENOMEM;
214
215 return 0;
216 }
217
tegra_clk_init(void __iomem * regs,int num,int banks)218 struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
219 {
220 clk_base = regs;
221
222 if (WARN_ON(banks > ARRAY_SIZE(periph_regs)))
223 return NULL;
224
225 periph_clk_enb_refcnt = kcalloc(32 * banks,
226 sizeof(*periph_clk_enb_refcnt),
227 GFP_KERNEL);
228 if (!periph_clk_enb_refcnt)
229 return NULL;
230
231 periph_banks = banks;
232
233 clks = kcalloc(num, sizeof(struct clk *), GFP_KERNEL);
234 if (!clks) {
235 kfree(periph_clk_enb_refcnt);
236 return NULL;
237 }
238
239 clk_num = num;
240
241 if (IS_ENABLED(CONFIG_PM_SLEEP)) {
242 if (tegra_clk_periph_ctx_init(banks)) {
243 kfree(periph_clk_enb_refcnt);
244 kfree(clks);
245 return NULL;
246 }
247 }
248
249 return clks;
250 }
251
tegra_init_dup_clks(struct tegra_clk_duplicate * dup_list,struct clk * clks[],int clk_max)252 void __init tegra_init_dup_clks(struct tegra_clk_duplicate *dup_list,
253 struct clk *clks[], int clk_max)
254 {
255 struct clk *clk;
256
257 for (; dup_list->clk_id < clk_max; dup_list++) {
258 clk = clks[dup_list->clk_id];
259 dup_list->lookup.clk = clk;
260 clkdev_add(&dup_list->lookup);
261 }
262 }
263
tegra_init_from_table(struct tegra_clk_init_table * tbl,struct clk * clks[],int clk_max)264 void __init tegra_init_from_table(struct tegra_clk_init_table *tbl,
265 struct clk *clks[], int clk_max)
266 {
267 struct clk *clk;
268
269 for (; tbl->clk_id < clk_max; tbl++) {
270 clk = clks[tbl->clk_id];
271 if (IS_ERR_OR_NULL(clk)) {
272 pr_err("%s: invalid entry %ld in clks array for id %d\n",
273 __func__, PTR_ERR(clk), tbl->clk_id);
274 WARN_ON(1);
275
276 continue;
277 }
278
279 if (tbl->parent_id < clk_max) {
280 struct clk *parent = clks[tbl->parent_id];
281 if (clk_set_parent(clk, parent)) {
282 pr_err("%s: Failed to set parent %s of %s\n",
283 __func__, __clk_get_name(parent),
284 __clk_get_name(clk));
285 WARN_ON(1);
286 }
287 }
288
289 if (tbl->rate)
290 if (clk_set_rate(clk, tbl->rate)) {
291 pr_err("%s: Failed to set rate %lu of %s\n",
292 __func__, tbl->rate,
293 __clk_get_name(clk));
294 WARN_ON(1);
295 }
296
297 if (tbl->state)
298 if (clk_prepare_enable(clk)) {
299 pr_err("%s: Failed to enable %s\n", __func__,
300 __clk_get_name(clk));
301 WARN_ON(1);
302 }
303 }
304 }
305
306 static const struct reset_control_ops rst_ops = {
307 .assert = tegra_clk_rst_assert,
308 .deassert = tegra_clk_rst_deassert,
309 .reset = tegra_clk_rst_reset,
310 };
311
312 static struct reset_controller_dev rst_ctlr = {
313 .ops = &rst_ops,
314 .owner = THIS_MODULE,
315 .of_reset_n_cells = 1,
316 };
317
tegra_add_of_provider(struct device_node * np,void * clk_src_onecell_get)318 void __init tegra_add_of_provider(struct device_node *np,
319 void *clk_src_onecell_get)
320 {
321 int i;
322
323 for (i = 0; i < clk_num; i++) {
324 if (IS_ERR(clks[i])) {
325 pr_err
326 ("Tegra clk %d: register failed with %ld\n",
327 i, PTR_ERR(clks[i]));
328 }
329 if (!clks[i])
330 clks[i] = ERR_PTR(-EINVAL);
331 }
332
333 clk_data.clks = clks;
334 clk_data.clk_num = clk_num;
335 of_clk_add_provider(np, clk_src_onecell_get, &clk_data);
336
337 rst_ctlr.of_node = np;
338 rst_ctlr.nr_resets = periph_banks * 32 + num_special_reset;
339 reset_controller_register(&rst_ctlr);
340 }
341
tegra_init_special_resets(unsigned int num,int (* assert)(unsigned long),int (* deassert)(unsigned long))342 void __init tegra_init_special_resets(unsigned int num,
343 int (*assert)(unsigned long),
344 int (*deassert)(unsigned long))
345 {
346 num_special_reset = num;
347 special_reset_assert = assert;
348 special_reset_deassert = deassert;
349 }
350
tegra_register_devclks(struct tegra_devclk * dev_clks,int num)351 void __init tegra_register_devclks(struct tegra_devclk *dev_clks, int num)
352 {
353 int i;
354
355 for (i = 0; i < num; i++, dev_clks++)
356 clk_register_clkdev(clks[dev_clks->dt_id], dev_clks->con_id,
357 dev_clks->dev_id);
358
359 for (i = 0; i < clk_num; i++) {
360 if (!IS_ERR_OR_NULL(clks[i]))
361 clk_register_clkdev(clks[i], __clk_get_name(clks[i]),
362 "tegra-clk-debug");
363 }
364 }
365
tegra_lookup_dt_id(int clk_id,struct tegra_clk * tegra_clk)366 struct clk ** __init tegra_lookup_dt_id(int clk_id,
367 struct tegra_clk *tegra_clk)
368 {
369 if (tegra_clk[clk_id].present)
370 return &clks[tegra_clk[clk_id].dt_id];
371 else
372 return NULL;
373 }
374
375 tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
376
tegra_clocks_apply_init_table(void)377 static int __init tegra_clocks_apply_init_table(void)
378 {
379 if (!tegra_clk_apply_init_table)
380 return 0;
381
382 tegra_clk_apply_init_table();
383
384 return 0;
385 }
386 arch_initcall(tegra_clocks_apply_init_table);
387