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/of_platform.h>
13#include <linux/clk/tegra.h>
14#include <linux/platform_device.h>
15#include <linux/pm_runtime.h>
16#include <linux/reset-controller.h>
17#include <linux/string_helpers.h>
18
19#include <soc/tegra/fuse.h>
20
21#include "clk.h"
22
23/* Global data of Tegra CPU CAR ops */
24static struct device_node *tegra_car_np;
25static struct tegra_cpu_car_ops dummy_car_ops;
26struct tegra_cpu_car_ops *tegra_cpu_car_ops = &dummy_car_ops;
27
28int *periph_clk_enb_refcnt;
29static int periph_banks;
30static u32 *periph_state_ctx;
31static struct clk **clks;
32static int clk_num;
33static struct clk_onecell_data clk_data;
34
35/* Handlers for SoC-specific reset lines */
36static int (*special_reset_assert)(unsigned long);
37static int (*special_reset_deassert)(unsigned long);
38static unsigned int num_special_reset;
39
40static const struct tegra_clk_periph_regs periph_regs[] = {
41 [0] = {
42 .enb_reg = CLK_OUT_ENB_L,
43 .enb_set_reg = CLK_OUT_ENB_SET_L,
44 .enb_clr_reg = CLK_OUT_ENB_CLR_L,
45 .rst_reg = RST_DEVICES_L,
46 .rst_set_reg = RST_DEVICES_SET_L,
47 .rst_clr_reg = RST_DEVICES_CLR_L,
48 },
49 [1] = {
50 .enb_reg = CLK_OUT_ENB_H,
51 .enb_set_reg = CLK_OUT_ENB_SET_H,
52 .enb_clr_reg = CLK_OUT_ENB_CLR_H,
53 .rst_reg = RST_DEVICES_H,
54 .rst_set_reg = RST_DEVICES_SET_H,
55 .rst_clr_reg = RST_DEVICES_CLR_H,
56 },
57 [2] = {
58 .enb_reg = CLK_OUT_ENB_U,
59 .enb_set_reg = CLK_OUT_ENB_SET_U,
60 .enb_clr_reg = CLK_OUT_ENB_CLR_U,
61 .rst_reg = RST_DEVICES_U,
62 .rst_set_reg = RST_DEVICES_SET_U,
63 .rst_clr_reg = RST_DEVICES_CLR_U,
64 },
65 [3] = {
66 .enb_reg = CLK_OUT_ENB_V,
67 .enb_set_reg = CLK_OUT_ENB_SET_V,
68 .enb_clr_reg = CLK_OUT_ENB_CLR_V,
69 .rst_reg = RST_DEVICES_V,
70 .rst_set_reg = RST_DEVICES_SET_V,
71 .rst_clr_reg = RST_DEVICES_CLR_V,
72 },
73 [4] = {
74 .enb_reg = CLK_OUT_ENB_W,
75 .enb_set_reg = CLK_OUT_ENB_SET_W,
76 .enb_clr_reg = CLK_OUT_ENB_CLR_W,
77 .rst_reg = RST_DEVICES_W,
78 .rst_set_reg = RST_DEVICES_SET_W,
79 .rst_clr_reg = RST_DEVICES_CLR_W,
80 },
81 [5] = {
82 .enb_reg = CLK_OUT_ENB_X,
83 .enb_set_reg = CLK_OUT_ENB_SET_X,
84 .enb_clr_reg = CLK_OUT_ENB_CLR_X,
85 .rst_reg = RST_DEVICES_X,
86 .rst_set_reg = RST_DEVICES_SET_X,
87 .rst_clr_reg = RST_DEVICES_CLR_X,
88 },
89 [6] = {
90 .enb_reg = CLK_OUT_ENB_Y,
91 .enb_set_reg = CLK_OUT_ENB_SET_Y,
92 .enb_clr_reg = CLK_OUT_ENB_CLR_Y,
93 .rst_reg = RST_DEVICES_Y,
94 .rst_set_reg = RST_DEVICES_SET_Y,
95 .rst_clr_reg = RST_DEVICES_CLR_Y,
96 },
97};
98
99static void __iomem *clk_base;
100
101static int tegra_clk_rst_assert(struct reset_controller_dev *rcdev,
102 unsigned long id)
103{
104 /*
105 * If peripheral is on the APB bus then we must read the APB bus to
106 * flush the write operation in apb bus. This will avoid peripheral
107 * access after disabling clock. Since the reset driver has no
108 * knowledge of which reset IDs represent which devices, simply do
109 * this all the time.
110 */
111 tegra_read_chipid();
112
113 if (id < periph_banks * 32) {
114 writel_relaxed(BIT(id % 32),
115 clk_base + periph_regs[id / 32].rst_set_reg);
116 return 0;
117 } else if (id < periph_banks * 32 + num_special_reset) {
118 return special_reset_assert(id);
119 }
120
121 return -EINVAL;
122}
123
124static int tegra_clk_rst_deassert(struct reset_controller_dev *rcdev,
125 unsigned long id)
126{
127 if (id < periph_banks * 32) {
128 writel_relaxed(BIT(id % 32),
129 clk_base + periph_regs[id / 32].rst_clr_reg);
130 return 0;
131 } else if (id < periph_banks * 32 + num_special_reset) {
132 return special_reset_deassert(id);
133 }
134
135 return -EINVAL;
136}
137
138static int tegra_clk_rst_reset(struct reset_controller_dev *rcdev,
139 unsigned long id)
140{
141 int err;
142
143 err = tegra_clk_rst_assert(rcdev, id);
144 if (err)
145 return err;
146
147 udelay(1);
148
149 return tegra_clk_rst_deassert(rcdev, id);
150}
151
152const struct tegra_clk_periph_regs *get_reg_bank(int clkid)
153{
154 int reg_bank = clkid / 32;
155
156 if (reg_bank < periph_banks)
157 return &periph_regs[reg_bank];
158 else {
159 WARN_ON(1);
160 return NULL;
161 }
162}
163
164void tegra_clk_set_pllp_out_cpu(bool enable)
165{
166 u32 val;
167
168 val = readl_relaxed(clk_base + CLK_OUT_ENB_Y);
169 if (enable)
170 val |= CLK_ENB_PLLP_OUT_CPU;
171 else
172 val &= ~CLK_ENB_PLLP_OUT_CPU;
173
174 writel_relaxed(val, clk_base + CLK_OUT_ENB_Y);
175}
176
177void tegra_clk_periph_suspend(void)
178{
179 unsigned int i, idx;
180
181 idx = 0;
182 for (i = 0; i < periph_banks; i++, idx++)
183 periph_state_ctx[idx] =
184 readl_relaxed(clk_base + periph_regs[i].enb_reg);
185
186 for (i = 0; i < periph_banks; i++, idx++)
187 periph_state_ctx[idx] =
188 readl_relaxed(clk_base + periph_regs[i].rst_reg);
189}
190
191void tegra_clk_periph_resume(void)
192{
193 unsigned int i, idx;
194
195 idx = 0;
196 for (i = 0; i < periph_banks; i++, idx++)
197 writel_relaxed(periph_state_ctx[idx],
198 clk_base + periph_regs[i].enb_reg);
199 /*
200 * All non-boot peripherals will be in reset state on resume.
201 * Wait for 5us of reset propagation delay before de-asserting
202 * the peripherals based on the saved context.
203 */
204 fence_udelay(5, clk_base);
205
206 for (i = 0; i < periph_banks; i++, idx++)
207 writel_relaxed(periph_state_ctx[idx],
208 clk_base + periph_regs[i].rst_reg);
209
210 fence_udelay(2, clk_base);
211}
212
213static int tegra_clk_periph_ctx_init(int banks)
214{
215 periph_state_ctx = kcalloc(n: 2 * banks, size: sizeof(*periph_state_ctx),
216 GFP_KERNEL);
217 if (!periph_state_ctx)
218 return -ENOMEM;
219
220 return 0;
221}
222
223struct clk ** __init tegra_clk_init(void __iomem *regs, int num, int banks)
224{
225 clk_base = regs;
226
227 if (WARN_ON(banks > ARRAY_SIZE(periph_regs)))
228 return NULL;
229
230 periph_clk_enb_refcnt = kcalloc(n: 32 * banks,
231 size: sizeof(*periph_clk_enb_refcnt),
232 GFP_KERNEL);
233 if (!periph_clk_enb_refcnt)
234 return NULL;
235
236 periph_banks = banks;
237
238 clks = kcalloc(n: num, size: sizeof(struct clk *), GFP_KERNEL);
239 if (!clks) {
240 kfree(objp: periph_clk_enb_refcnt);
241 return NULL;
242 }
243
244 clk_num = num;
245
246 if (IS_ENABLED(CONFIG_PM_SLEEP)) {
247 if (tegra_clk_periph_ctx_init(banks)) {
248 kfree(objp: periph_clk_enb_refcnt);
249 kfree(objp: clks);
250 return NULL;
251 }
252 }
253
254 return clks;
255}
256
257void __init tegra_init_dup_clks(struct tegra_clk_duplicate *dup_list,
258 struct clk *clks[], int clk_max)
259{
260 struct clk *clk;
261
262 for (; dup_list->clk_id < clk_max; dup_list++) {
263 clk = clks[dup_list->clk_id];
264 dup_list->lookup.clk = clk;
265 clkdev_add(cl: &dup_list->lookup);
266 }
267}
268
269void tegra_init_from_table(struct tegra_clk_init_table *tbl,
270 struct clk *clks[], int clk_max)
271{
272 struct clk *clk;
273
274 for (; tbl->clk_id < clk_max; tbl++) {
275 clk = clks[tbl->clk_id];
276 if (IS_ERR_OR_NULL(ptr: clk)) {
277 pr_err("%s: invalid entry %ld in clks array for id %d\n",
278 __func__, PTR_ERR(clk), tbl->clk_id);
279 WARN_ON(1);
280
281 continue;
282 }
283
284 if (tbl->parent_id < clk_max) {
285 struct clk *parent = clks[tbl->parent_id];
286 if (clk_set_parent(clk, parent)) {
287 pr_err("%s: Failed to set parent %s of %s\n",
288 __func__, __clk_get_name(parent),
289 __clk_get_name(clk));
290 WARN_ON(1);
291 }
292 }
293
294 if (tbl->rate)
295 if (clk_set_rate(clk, rate: tbl->rate)) {
296 pr_err("%s: Failed to set rate %lu of %s\n",
297 __func__, tbl->rate,
298 __clk_get_name(clk));
299 WARN_ON(1);
300 }
301
302 if (tbl->state)
303 if (clk_prepare_enable(clk)) {
304 pr_err("%s: Failed to enable %s\n", __func__,
305 __clk_get_name(clk));
306 WARN_ON(1);
307 }
308 }
309}
310
311static const struct reset_control_ops rst_ops = {
312 .assert = tegra_clk_rst_assert,
313 .deassert = tegra_clk_rst_deassert,
314 .reset = tegra_clk_rst_reset,
315};
316
317static struct reset_controller_dev rst_ctlr = {
318 .ops = &rst_ops,
319 .owner = THIS_MODULE,
320 .of_reset_n_cells = 1,
321};
322
323void __init tegra_add_of_provider(struct device_node *np,
324 void *clk_src_onecell_get)
325{
326 int i;
327
328 tegra_car_np = np;
329
330 for (i = 0; i < clk_num; i++) {
331 if (IS_ERR(ptr: clks[i])) {
332 pr_err
333 ("Tegra clk %d: register failed with %ld\n",
334 i, PTR_ERR(clks[i]));
335 }
336 if (!clks[i])
337 clks[i] = ERR_PTR(error: -EINVAL);
338 }
339
340 clk_data.clks = clks;
341 clk_data.clk_num = clk_num;
342 of_clk_add_provider(np, clk_src_get: clk_src_onecell_get, data: &clk_data);
343
344 rst_ctlr.of_node = np;
345 rst_ctlr.nr_resets = periph_banks * 32 + num_special_reset;
346 reset_controller_register(rcdev: &rst_ctlr);
347}
348
349void __init tegra_init_special_resets(unsigned int num,
350 int (*assert)(unsigned long),
351 int (*deassert)(unsigned long))
352{
353 num_special_reset = num;
354 special_reset_assert = assert;
355 special_reset_deassert = deassert;
356}
357
358void tegra_register_devclks(struct tegra_devclk *dev_clks, int num)
359{
360 int i;
361
362 for (i = 0; i < num; i++, dev_clks++)
363 clk_register_clkdev(clks[dev_clks->dt_id], dev_clks->con_id,
364 dev_clks->dev_id);
365
366 for (i = 0; i < clk_num; i++) {
367 if (!IS_ERR_OR_NULL(ptr: clks[i]))
368 clk_register_clkdev(clks[i], __clk_get_name(clk: clks[i]),
369 "tegra-clk-debug");
370 }
371}
372
373struct clk ** __init tegra_lookup_dt_id(int clk_id,
374 struct tegra_clk *tegra_clk)
375{
376 if (tegra_clk[clk_id].present)
377 return &clks[tegra_clk[clk_id].dt_id];
378 else
379 return NULL;
380}
381
382static struct device_node *tegra_clk_get_of_node(struct clk_hw *hw)
383{
384 struct device_node *np;
385 char *node_name;
386
387 node_name = kstrdup_and_replace(src: hw->init->name, old: '_', new: '-', GFP_KERNEL);
388 if (!node_name)
389 return NULL;
390
391 for_each_child_of_node(tegra_car_np, np) {
392 if (!strcmp(np->name, node_name))
393 break;
394 }
395
396 kfree(objp: node_name);
397
398 return np;
399}
400
401struct clk *tegra_clk_dev_register(struct clk_hw *hw)
402{
403 struct platform_device *pdev, *parent;
404 const char *dev_name = NULL;
405 struct device *dev = NULL;
406 struct device_node *np;
407
408 np = tegra_clk_get_of_node(hw);
409
410 if (!of_device_is_available(device: np))
411 goto put_node;
412
413 dev_name = kasprintf(GFP_KERNEL, fmt: "tegra_clk_%s", hw->init->name);
414 if (!dev_name)
415 goto put_node;
416
417 parent = of_find_device_by_node(np: tegra_car_np);
418 if (parent) {
419 pdev = of_platform_device_create(np, bus_id: dev_name, parent: &parent->dev);
420 put_device(dev: &parent->dev);
421
422 if (!pdev) {
423 pr_err("%s: failed to create device for %pOF\n",
424 __func__, np);
425 goto free_name;
426 }
427
428 dev = &pdev->dev;
429 pm_runtime_enable(dev);
430 } else {
431 WARN(1, "failed to find device for %pOF\n", tegra_car_np);
432 }
433
434free_name:
435 kfree(objp: dev_name);
436put_node:
437 of_node_put(node: np);
438
439 return clk_register(dev, hw);
440}
441
442tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
443
444static int __init tegra_clocks_apply_init_table(void)
445{
446 if (!tegra_clk_apply_init_table)
447 return 0;
448
449 tegra_clk_apply_init_table();
450
451 return 0;
452}
453arch_initcall(tegra_clocks_apply_init_table);
454

source code of linux/drivers/clk/tegra/clk.c