1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * TI clock support
4 *
5 * Copyright (C) 2013 Texas Instruments, Inc.
6 *
7 * Tero Kristo <t-kristo@ti.com>
8 */
9
10 #include <linux/clk.h>
11 #include <linux/clk-provider.h>
12 #include <linux/clkdev.h>
13 #include <linux/clk/ti.h>
14 #include <linux/io.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/list.h>
18 #include <linux/regmap.h>
19 #include <linux/memblock.h>
20 #include <linux/device.h>
21
22 #include "clock.h"
23
24 #undef pr_fmt
25 #define pr_fmt(fmt) "%s: " fmt, __func__
26
27 static LIST_HEAD(clk_hw_omap_clocks);
28 struct ti_clk_ll_ops *ti_clk_ll_ops;
29 static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS];
30
31 struct ti_clk_features ti_clk_features;
32
33 struct clk_iomap {
34 struct regmap *regmap;
35 void __iomem *mem;
36 };
37
38 static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS];
39
clk_memmap_writel(u32 val,const struct clk_omap_reg * reg)40 static void clk_memmap_writel(u32 val, const struct clk_omap_reg *reg)
41 {
42 struct clk_iomap *io = clk_memmaps[reg->index];
43
44 if (reg->ptr)
45 writel_relaxed(val, reg->ptr);
46 else if (io->regmap)
47 regmap_write(io->regmap, reg->offset, val);
48 else
49 writel_relaxed(val, io->mem + reg->offset);
50 }
51
_clk_rmw(u32 val,u32 mask,void __iomem * ptr)52 static void _clk_rmw(u32 val, u32 mask, void __iomem *ptr)
53 {
54 u32 v;
55
56 v = readl_relaxed(ptr);
57 v &= ~mask;
58 v |= val;
59 writel_relaxed(v, ptr);
60 }
61
clk_memmap_rmw(u32 val,u32 mask,const struct clk_omap_reg * reg)62 static void clk_memmap_rmw(u32 val, u32 mask, const struct clk_omap_reg *reg)
63 {
64 struct clk_iomap *io = clk_memmaps[reg->index];
65
66 if (reg->ptr) {
67 _clk_rmw(val, mask, reg->ptr);
68 } else if (io->regmap) {
69 regmap_update_bits(io->regmap, reg->offset, mask, val);
70 } else {
71 _clk_rmw(val, mask, io->mem + reg->offset);
72 }
73 }
74
clk_memmap_readl(const struct clk_omap_reg * reg)75 static u32 clk_memmap_readl(const struct clk_omap_reg *reg)
76 {
77 u32 val;
78 struct clk_iomap *io = clk_memmaps[reg->index];
79
80 if (reg->ptr)
81 val = readl_relaxed(reg->ptr);
82 else if (io->regmap)
83 regmap_read(io->regmap, reg->offset, &val);
84 else
85 val = readl_relaxed(io->mem + reg->offset);
86
87 return val;
88 }
89
90 /**
91 * ti_clk_setup_ll_ops - setup low level clock operations
92 * @ops: low level clock ops descriptor
93 *
94 * Sets up low level clock operations for TI clock driver. This is used
95 * to provide various callbacks for the clock driver towards platform
96 * specific code. Returns 0 on success, -EBUSY if ll_ops have been
97 * registered already.
98 */
ti_clk_setup_ll_ops(struct ti_clk_ll_ops * ops)99 int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops)
100 {
101 if (ti_clk_ll_ops) {
102 pr_err("Attempt to register ll_ops multiple times.\n");
103 return -EBUSY;
104 }
105
106 ti_clk_ll_ops = ops;
107 ops->clk_readl = clk_memmap_readl;
108 ops->clk_writel = clk_memmap_writel;
109 ops->clk_rmw = clk_memmap_rmw;
110
111 return 0;
112 }
113
114 /*
115 * Eventually we could standardize to using '_' for clk-*.c files to follow the
116 * TRM naming and leave out the tmp name here.
117 */
ti_find_clock_provider(struct device_node * from,const char * name)118 static struct device_node *ti_find_clock_provider(struct device_node *from,
119 const char *name)
120 {
121 struct device_node *np;
122 bool found = false;
123 const char *n;
124 char *tmp;
125
126 tmp = kstrdup(name, GFP_KERNEL);
127 if (!tmp)
128 return NULL;
129 strreplace(tmp, '-', '_');
130
131 /* Node named "clock" with "clock-output-names" */
132 for_each_of_allnodes_from(from, np) {
133 if (of_property_read_string_index(np, "clock-output-names",
134 0, &n))
135 continue;
136
137 if (!strncmp(n, tmp, strlen(tmp))) {
138 of_node_get(np);
139 found = true;
140 break;
141 }
142 }
143 kfree(tmp);
144
145 if (found) {
146 of_node_put(from);
147 return np;
148 }
149
150 /* Fall back to using old node name base provider name */
151 return of_find_node_by_name(from, name);
152 }
153
154 /**
155 * ti_dt_clocks_register - register DT alias clocks during boot
156 * @oclks: list of clocks to register
157 *
158 * Register alias or non-standard DT clock entries during boot. By
159 * default, DT clocks are found based on their clock-output-names
160 * property, or the clock node name for legacy cases. If any
161 * additional con-id / dev-id -> clock mapping is required, use this
162 * function to list these.
163 */
ti_dt_clocks_register(struct ti_dt_clk oclks[])164 void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])
165 {
166 struct ti_dt_clk *c;
167 struct device_node *node, *parent, *child;
168 struct clk *clk;
169 struct of_phandle_args clkspec;
170 char buf[64];
171 char *ptr;
172 char *tags[2];
173 int i;
174 int num_args;
175 int ret;
176 static bool clkctrl_nodes_missing;
177 static bool has_clkctrl_data;
178 static bool compat_mode;
179
180 compat_mode = ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT;
181
182 for (c = oclks; c->node_name != NULL; c++) {
183 strcpy(buf, c->node_name);
184 ptr = buf;
185 for (i = 0; i < 2; i++)
186 tags[i] = NULL;
187 num_args = 0;
188 while (*ptr) {
189 if (*ptr == ':') {
190 if (num_args >= 2) {
191 pr_warn("Bad number of tags on %s\n",
192 c->node_name);
193 return;
194 }
195 tags[num_args++] = ptr + 1;
196 *ptr = 0;
197 }
198 ptr++;
199 }
200
201 if (num_args && clkctrl_nodes_missing)
202 continue;
203
204 node = ti_find_clock_provider(NULL, buf);
205 if (num_args && compat_mode) {
206 parent = node;
207 child = of_get_child_by_name(parent, "clock");
208 if (!child)
209 child = of_get_child_by_name(parent, "clk");
210 if (child) {
211 of_node_put(parent);
212 node = child;
213 }
214 }
215
216 clkspec.np = node;
217 clkspec.args_count = num_args;
218 for (i = 0; i < num_args; i++) {
219 ret = kstrtoint(tags[i], i ? 10 : 16, clkspec.args + i);
220 if (ret) {
221 pr_warn("Bad tag in %s at %d: %s\n",
222 c->node_name, i, tags[i]);
223 of_node_put(node);
224 return;
225 }
226 }
227 clk = of_clk_get_from_provider(&clkspec);
228 of_node_put(node);
229 if (!IS_ERR(clk)) {
230 c->lk.clk = clk;
231 clkdev_add(&c->lk);
232 } else {
233 if (num_args && !has_clkctrl_data) {
234 struct device_node *np;
235
236 np = of_find_compatible_node(NULL, NULL,
237 "ti,clkctrl");
238 if (np) {
239 has_clkctrl_data = true;
240 of_node_put(np);
241 } else {
242 clkctrl_nodes_missing = true;
243
244 pr_warn("missing clkctrl nodes, please update your dts.\n");
245 continue;
246 }
247 }
248
249 pr_warn("failed to lookup clock node %s, ret=%ld\n",
250 c->node_name, PTR_ERR(clk));
251 }
252 }
253 }
254
255 struct clk_init_item {
256 struct device_node *node;
257 void *user;
258 ti_of_clk_init_cb_t func;
259 struct list_head link;
260 };
261
262 static LIST_HEAD(retry_list);
263
264 /**
265 * ti_clk_retry_init - retries a failed clock init at later phase
266 * @node: device not for the clock
267 * @user: user data pointer
268 * @func: init function to be called for the clock
269 *
270 * Adds a failed clock init to the retry list. The retry list is parsed
271 * once all the other clocks have been initialized.
272 */
ti_clk_retry_init(struct device_node * node,void * user,ti_of_clk_init_cb_t func)273 int __init ti_clk_retry_init(struct device_node *node, void *user,
274 ti_of_clk_init_cb_t func)
275 {
276 struct clk_init_item *retry;
277
278 pr_debug("%pOFn: adding to retry list...\n", node);
279 retry = kzalloc(sizeof(*retry), GFP_KERNEL);
280 if (!retry)
281 return -ENOMEM;
282
283 retry->node = node;
284 retry->func = func;
285 retry->user = user;
286 list_add(&retry->link, &retry_list);
287
288 return 0;
289 }
290
291 /**
292 * ti_clk_get_reg_addr - get register address for a clock register
293 * @node: device node for the clock
294 * @index: register index from the clock node
295 * @reg: pointer to target register struct
296 *
297 * Builds clock register address from device tree information, and returns
298 * the data via the provided output pointer @reg. Returns 0 on success,
299 * negative error value on failure.
300 */
ti_clk_get_reg_addr(struct device_node * node,int index,struct clk_omap_reg * reg)301 int ti_clk_get_reg_addr(struct device_node *node, int index,
302 struct clk_omap_reg *reg)
303 {
304 u32 val;
305 int i;
306
307 for (i = 0; i < CLK_MAX_MEMMAPS; i++) {
308 if (clocks_node_ptr[i] == node->parent)
309 break;
310 if (clocks_node_ptr[i] == node->parent->parent)
311 break;
312 }
313
314 if (i == CLK_MAX_MEMMAPS) {
315 pr_err("clk-provider not found for %pOFn!\n", node);
316 return -ENOENT;
317 }
318
319 reg->index = i;
320
321 if (of_property_read_u32_index(node, "reg", index, &val)) {
322 if (of_property_read_u32_index(node->parent, "reg",
323 index, &val)) {
324 pr_err("%pOFn or parent must have reg[%d]!\n",
325 node, index);
326 return -EINVAL;
327 }
328 }
329
330 reg->offset = val;
331 reg->ptr = NULL;
332
333 return 0;
334 }
335
ti_clk_latch(struct clk_omap_reg * reg,s8 shift)336 void ti_clk_latch(struct clk_omap_reg *reg, s8 shift)
337 {
338 u32 latch;
339
340 if (shift < 0)
341 return;
342
343 latch = 1 << shift;
344
345 ti_clk_ll_ops->clk_rmw(latch, latch, reg);
346 ti_clk_ll_ops->clk_rmw(0, latch, reg);
347 ti_clk_ll_ops->clk_readl(reg); /* OCP barrier */
348 }
349
350 /**
351 * omap2_clk_provider_init - init master clock provider
352 * @parent: master node
353 * @index: internal index for clk_reg_ops
354 * @syscon: syscon regmap pointer for accessing clock registers
355 * @mem: iomem pointer for the clock provider memory area, only used if
356 * syscon is not provided
357 *
358 * Initializes a master clock IP block. This basically sets up the
359 * mapping from clocks node to the memory map index. All the clocks
360 * are then initialized through the common of_clk_init call, and the
361 * clocks will access their memory maps based on the node layout.
362 * Returns 0 in success.
363 */
omap2_clk_provider_init(struct device_node * parent,int index,struct regmap * syscon,void __iomem * mem)364 int __init omap2_clk_provider_init(struct device_node *parent, int index,
365 struct regmap *syscon, void __iomem *mem)
366 {
367 struct device_node *clocks;
368 struct clk_iomap *io;
369
370 /* get clocks for this parent */
371 clocks = of_get_child_by_name(parent, "clocks");
372 if (!clocks) {
373 pr_err("%pOFn missing 'clocks' child node.\n", parent);
374 return -EINVAL;
375 }
376
377 /* add clocks node info */
378 clocks_node_ptr[index] = clocks;
379
380 io = kzalloc(sizeof(*io), GFP_KERNEL);
381 if (!io)
382 return -ENOMEM;
383
384 io->regmap = syscon;
385 io->mem = mem;
386
387 clk_memmaps[index] = io;
388
389 return 0;
390 }
391
392 /**
393 * omap2_clk_legacy_provider_init - initialize a legacy clock provider
394 * @index: index for the clock provider
395 * @mem: iomem pointer for the clock provider memory area
396 *
397 * Initializes a legacy clock provider memory mapping.
398 */
omap2_clk_legacy_provider_init(int index,void __iomem * mem)399 void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem)
400 {
401 struct clk_iomap *io;
402
403 io = memblock_alloc(sizeof(*io), SMP_CACHE_BYTES);
404 if (!io)
405 panic("%s: Failed to allocate %zu bytes\n", __func__,
406 sizeof(*io));
407
408 io->mem = mem;
409
410 clk_memmaps[index] = io;
411 }
412
413 /**
414 * ti_dt_clk_init_retry_clks - init clocks from the retry list
415 *
416 * Initializes any clocks that have failed to initialize before,
417 * reasons being missing parent node(s) during earlier init. This
418 * typically happens only for DPLLs which need to have both of their
419 * parent clocks ready during init.
420 */
ti_dt_clk_init_retry_clks(void)421 void ti_dt_clk_init_retry_clks(void)
422 {
423 struct clk_init_item *retry;
424 struct clk_init_item *tmp;
425 int retries = 5;
426
427 while (!list_empty(&retry_list) && retries) {
428 list_for_each_entry_safe(retry, tmp, &retry_list, link) {
429 pr_debug("retry-init: %pOFn\n", retry->node);
430 retry->func(retry->user, retry->node);
431 list_del(&retry->link);
432 kfree(retry);
433 }
434 retries--;
435 }
436 }
437
438 static const struct of_device_id simple_clk_match_table[] __initconst = {
439 { .compatible = "fixed-clock" },
440 { .compatible = "fixed-factor-clock" },
441 { }
442 };
443
444 /**
445 * ti_dt_clk_name - init clock name from first output name or node name
446 * @np: device node
447 *
448 * Use the first clock-output-name for the clock name if found. Fall back
449 * to legacy naming based on node name.
450 */
ti_dt_clk_name(struct device_node * np)451 const char *ti_dt_clk_name(struct device_node *np)
452 {
453 const char *name;
454
455 if (!of_property_read_string_index(np, "clock-output-names", 0,
456 &name))
457 return name;
458
459 return np->name;
460 }
461
462 /**
463 * ti_clk_add_aliases - setup clock aliases
464 *
465 * Sets up any missing clock aliases. No return value.
466 */
ti_clk_add_aliases(void)467 void __init ti_clk_add_aliases(void)
468 {
469 struct device_node *np;
470 struct clk *clk;
471
472 for_each_matching_node(np, simple_clk_match_table) {
473 struct of_phandle_args clkspec;
474
475 clkspec.np = np;
476 clk = of_clk_get_from_provider(&clkspec);
477
478 ti_clk_add_alias(NULL, clk, ti_dt_clk_name(np));
479 }
480 }
481
482 /**
483 * ti_clk_setup_features - setup clock features flags
484 * @features: features definition to use
485 *
486 * Initializes the clock driver features flags based on platform
487 * provided data. No return value.
488 */
ti_clk_setup_features(struct ti_clk_features * features)489 void __init ti_clk_setup_features(struct ti_clk_features *features)
490 {
491 memcpy(&ti_clk_features, features, sizeof(*features));
492 }
493
494 /**
495 * ti_clk_get_features - get clock driver features flags
496 *
497 * Get TI clock driver features description. Returns a pointer
498 * to the current feature setup.
499 */
ti_clk_get_features(void)500 const struct ti_clk_features *ti_clk_get_features(void)
501 {
502 return &ti_clk_features;
503 }
504
505 /**
506 * omap2_clk_enable_init_clocks - prepare & enable a list of clocks
507 * @clk_names: ptr to an array of strings of clock names to enable
508 * @num_clocks: number of clock names in @clk_names
509 *
510 * Prepare and enable a list of clocks, named by @clk_names. No
511 * return value. XXX Deprecated; only needed until these clocks are
512 * properly claimed and enabled by the drivers or core code that uses
513 * them. XXX What code disables & calls clk_put on these clocks?
514 */
omap2_clk_enable_init_clocks(const char ** clk_names,u8 num_clocks)515 void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks)
516 {
517 struct clk *init_clk;
518 int i;
519
520 for (i = 0; i < num_clocks; i++) {
521 init_clk = clk_get(NULL, clk_names[i]);
522 if (WARN(IS_ERR(init_clk), "could not find init clock %s\n",
523 clk_names[i]))
524 continue;
525 clk_prepare_enable(init_clk);
526 }
527 }
528
529 /**
530 * ti_clk_add_alias - add a clock alias for a TI clock
531 * @dev: device alias for this clock
532 * @clk: clock handle to create alias for
533 * @con: connection ID for this clock
534 *
535 * Creates a clock alias for a TI clock. Allocates the clock lookup entry
536 * and assigns the data to it. Returns 0 if successful, negative error
537 * value otherwise.
538 */
ti_clk_add_alias(struct device * dev,struct clk * clk,const char * con)539 int ti_clk_add_alias(struct device *dev, struct clk *clk, const char *con)
540 {
541 struct clk_lookup *cl;
542
543 if (!clk)
544 return 0;
545
546 if (IS_ERR(clk))
547 return PTR_ERR(clk);
548
549 cl = kzalloc(sizeof(*cl), GFP_KERNEL);
550 if (!cl)
551 return -ENOMEM;
552
553 if (dev)
554 cl->dev_id = dev_name(dev);
555 cl->con_id = con;
556 cl->clk = clk;
557
558 clkdev_add(cl);
559
560 return 0;
561 }
562
563 /**
564 * ti_clk_register - register a TI clock to the common clock framework
565 * @dev: device for this clock
566 * @hw: hardware clock handle
567 * @con: connection ID for this clock
568 *
569 * Registers a TI clock to the common clock framework, and adds a clock
570 * alias for it. Returns a handle to the registered clock if successful,
571 * ERR_PTR value in failure.
572 */
ti_clk_register(struct device * dev,struct clk_hw * hw,const char * con)573 struct clk *ti_clk_register(struct device *dev, struct clk_hw *hw,
574 const char *con)
575 {
576 struct clk *clk;
577 int ret;
578
579 clk = clk_register(dev, hw);
580 if (IS_ERR(clk))
581 return clk;
582
583 ret = ti_clk_add_alias(dev, clk, con);
584 if (ret) {
585 clk_unregister(clk);
586 return ERR_PTR(ret);
587 }
588
589 return clk;
590 }
591
592 /**
593 * ti_clk_register_omap_hw - register a clk_hw_omap to the clock framework
594 * @dev: device for this clock
595 * @hw: hardware clock handle
596 * @con: connection ID for this clock
597 *
598 * Registers a clk_hw_omap clock to the clock framewor, adds a clock alias
599 * for it, and adds the list to the available clk_hw_omap type clocks.
600 * Returns a handle to the registered clock if successful, ERR_PTR value
601 * in failure.
602 */
ti_clk_register_omap_hw(struct device * dev,struct clk_hw * hw,const char * con)603 struct clk *ti_clk_register_omap_hw(struct device *dev, struct clk_hw *hw,
604 const char *con)
605 {
606 struct clk *clk;
607 struct clk_hw_omap *oclk;
608
609 clk = ti_clk_register(dev, hw, con);
610 if (IS_ERR(clk))
611 return clk;
612
613 oclk = to_clk_hw_omap(hw);
614
615 list_add(&oclk->node, &clk_hw_omap_clocks);
616
617 return clk;
618 }
619
620 /**
621 * omap2_clk_for_each - call function for each registered clk_hw_omap
622 * @fn: pointer to a callback function
623 *
624 * Call @fn for each registered clk_hw_omap, passing @hw to each
625 * function. @fn must return 0 for success or any other value for
626 * failure. If @fn returns non-zero, the iteration across clocks
627 * will stop and the non-zero return value will be passed to the
628 * caller of omap2_clk_for_each().
629 */
omap2_clk_for_each(int (* fn)(struct clk_hw_omap * hw))630 int omap2_clk_for_each(int (*fn)(struct clk_hw_omap *hw))
631 {
632 int ret;
633 struct clk_hw_omap *hw;
634
635 list_for_each_entry(hw, &clk_hw_omap_clocks, node) {
636 ret = (*fn)(hw);
637 if (ret)
638 break;
639 }
640
641 return ret;
642 }
643
644 /**
645 * omap2_clk_is_hw_omap - check if the provided clk_hw is OMAP clock
646 * @hw: clk_hw to check if it is an omap clock or not
647 *
648 * Checks if the provided clk_hw is OMAP clock or not. Returns true if
649 * it is, false otherwise.
650 */
omap2_clk_is_hw_omap(struct clk_hw * hw)651 bool omap2_clk_is_hw_omap(struct clk_hw *hw)
652 {
653 struct clk_hw_omap *oclk;
654
655 list_for_each_entry(oclk, &clk_hw_omap_clocks, node) {
656 if (&oclk->hw == hw)
657 return true;
658 }
659
660 return false;
661 }
662