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/string_helpers.h>
20#include <linux/memblock.h>
21#include <linux/device.h>
22
23#include "clock.h"
24
25#undef pr_fmt
26#define pr_fmt(fmt) "%s: " fmt, __func__
27
28static LIST_HEAD(clk_hw_omap_clocks);
29struct ti_clk_ll_ops *ti_clk_ll_ops;
30static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS];
31
32struct ti_clk_features ti_clk_features;
33
34struct clk_iomap {
35 struct regmap *regmap;
36 void __iomem *mem;
37};
38
39static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS];
40
41static void clk_memmap_writel(u32 val, const struct clk_omap_reg *reg)
42{
43 struct clk_iomap *io = clk_memmaps[reg->index];
44
45 if (reg->ptr)
46 writel_relaxed(val, reg->ptr);
47 else if (io->regmap)
48 regmap_write(map: io->regmap, reg: reg->offset, val);
49 else
50 writel_relaxed(val, io->mem + reg->offset);
51}
52
53static void _clk_rmw(u32 val, u32 mask, void __iomem *ptr)
54{
55 u32 v;
56
57 v = readl_relaxed(ptr);
58 v &= ~mask;
59 v |= val;
60 writel_relaxed(v, ptr);
61}
62
63static void clk_memmap_rmw(u32 val, u32 mask, const struct clk_omap_reg *reg)
64{
65 struct clk_iomap *io = clk_memmaps[reg->index];
66
67 if (reg->ptr) {
68 _clk_rmw(val, mask, ptr: reg->ptr);
69 } else if (io->regmap) {
70 regmap_update_bits(map: io->regmap, reg: reg->offset, mask, val);
71 } else {
72 _clk_rmw(val, mask, ptr: io->mem + reg->offset);
73 }
74}
75
76static u32 clk_memmap_readl(const struct clk_omap_reg *reg)
77{
78 u32 val;
79 struct clk_iomap *io = clk_memmaps[reg->index];
80
81 if (reg->ptr)
82 val = readl_relaxed(reg->ptr);
83 else if (io->regmap)
84 regmap_read(map: io->regmap, reg: reg->offset, val: &val);
85 else
86 val = readl_relaxed(io->mem + reg->offset);
87
88 return val;
89}
90
91/**
92 * ti_clk_setup_ll_ops - setup low level clock operations
93 * @ops: low level clock ops descriptor
94 *
95 * Sets up low level clock operations for TI clock driver. This is used
96 * to provide various callbacks for the clock driver towards platform
97 * specific code. Returns 0 on success, -EBUSY if ll_ops have been
98 * registered already.
99 */
100int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops)
101{
102 if (ti_clk_ll_ops) {
103 pr_err("Attempt to register ll_ops multiple times.\n");
104 return -EBUSY;
105 }
106
107 ti_clk_ll_ops = ops;
108 ops->clk_readl = clk_memmap_readl;
109 ops->clk_writel = clk_memmap_writel;
110 ops->clk_rmw = clk_memmap_rmw;
111
112 return 0;
113}
114
115/*
116 * Eventually we could standardize to using '_' for clk-*.c files to follow the
117 * TRM naming and leave out the tmp name here.
118 */
119static struct device_node *ti_find_clock_provider(struct device_node *from,
120 const char *name)
121{
122 struct device_node *np;
123 bool found = false;
124 const char *n;
125 char *tmp;
126
127 tmp = kstrdup_and_replace(src: name, old: '-', new: '_', GFP_KERNEL);
128 if (!tmp)
129 return NULL;
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, propname: "clock-output-names",
134 index: 0, output: &n))
135 continue;
136
137 if (!strncmp(n, tmp, strlen(tmp))) {
138 of_node_get(node: np);
139 found = true;
140 break;
141 }
142 }
143 kfree(objp: tmp);
144
145 if (found) {
146 of_node_put(node: 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 */
164void __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(p: buf, q: 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, name: buf);
205 if (num_args && compat_mode) {
206 parent = node;
207 child = of_get_child_by_name(node: parent, name: "clock");
208 if (!child)
209 child = of_get_child_by_name(node: parent, name: "clk");
210 if (child) {
211 of_node_put(node: 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(s: tags[i], base: i ? 10 : 16, res: 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: &clkspec);
228 of_node_put(node);
229 if (!IS_ERR(ptr: clk)) {
230 c->lk.clk = clk;
231 clkdev_add(cl: &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 compat: "ti,clkctrl");
238 if (np) {
239 has_clkctrl_data = true;
240 of_node_put(node: 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
255struct 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
262static LIST_HEAD(retry_list);
263
264/**
265 * ti_clk_retry_init - retries a failed clock init at later phase
266 * @node: device node 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 */
273int __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(size: 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(new: &retry->link, head: &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 */
301int 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(np: node, propname: "reg", index, out_value: &val)) {
322 if (of_property_read_u32_index(np: node->parent, propname: "reg",
323 index, out_value: &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
336void 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 */
364int __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(node: parent, name: "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(size: 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 */
399void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem)
400{
401 struct clk_iomap *io;
402
403 io = memblock_alloc(size: sizeof(*io), SMP_CACHE_BYTES);
404 if (!io)
405 panic(fmt: "%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 */
421void 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(head: &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(entry: &retry->link);
432 kfree(objp: retry);
433 }
434 retries--;
435 }
436}
437
438static 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 */
451const char *ti_dt_clk_name(struct device_node *np)
452{
453 const char *name;
454
455 if (!of_property_read_string_index(np, propname: "clock-output-names", index: 0,
456 output: &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 */
467void __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: &clkspec);
477
478 ti_clk_add_alias(clk, con: 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 */
489void __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 */
500const 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 */
515void 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, id: 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(clk: init_clk);
526 }
527}
528
529/**
530 * ti_clk_add_alias - add a clock alias for a TI clock
531 * @clk: clock handle to create alias for
532 * @con: connection ID for this clock
533 *
534 * Creates a clock alias for a TI clock. Allocates the clock lookup entry
535 * and assigns the data to it. Returns 0 if successful, negative error
536 * value otherwise.
537 */
538int ti_clk_add_alias(struct clk *clk, const char *con)
539{
540 struct clk_lookup *cl;
541
542 if (!clk)
543 return 0;
544
545 if (IS_ERR(ptr: clk))
546 return PTR_ERR(ptr: clk);
547
548 cl = kzalloc(size: sizeof(*cl), GFP_KERNEL);
549 if (!cl)
550 return -ENOMEM;
551
552 cl->con_id = con;
553 cl->clk = clk;
554
555 clkdev_add(cl);
556
557 return 0;
558}
559
560/**
561 * of_ti_clk_register - register a TI clock to the common clock framework
562 * @node: device node for this clock
563 * @hw: hardware clock handle
564 * @con: connection ID for this clock
565 *
566 * Registers a TI clock to the common clock framework, and adds a clock
567 * alias for it. Returns a handle to the registered clock if successful,
568 * ERR_PTR value in failure.
569 */
570struct clk *of_ti_clk_register(struct device_node *node, struct clk_hw *hw,
571 const char *con)
572{
573 struct clk *clk;
574 int ret;
575
576 ret = of_clk_hw_register(node, hw);
577 if (ret)
578 return ERR_PTR(error: ret);
579
580 clk = hw->clk;
581 ret = ti_clk_add_alias(clk, con);
582 if (ret) {
583 clk_unregister(clk);
584 return ERR_PTR(error: ret);
585 }
586
587 return clk;
588}
589
590/**
591 * of_ti_clk_register_omap_hw - register a clk_hw_omap to the clock framework
592 * @node: device node for this clock
593 * @hw: hardware clock handle
594 * @con: connection ID for this clock
595 *
596 * Registers a clk_hw_omap clock to the clock framewor, adds a clock alias
597 * for it, and adds the list to the available clk_hw_omap type clocks.
598 * Returns a handle to the registered clock if successful, ERR_PTR value
599 * in failure.
600 */
601struct clk *of_ti_clk_register_omap_hw(struct device_node *node,
602 struct clk_hw *hw, const char *con)
603{
604 struct clk *clk;
605 struct clk_hw_omap *oclk;
606
607 clk = of_ti_clk_register(node, hw, con);
608 if (IS_ERR(ptr: clk))
609 return clk;
610
611 oclk = to_clk_hw_omap(hw);
612
613 list_add(new: &oclk->node, head: &clk_hw_omap_clocks);
614
615 return clk;
616}
617
618/**
619 * omap2_clk_for_each - call function for each registered clk_hw_omap
620 * @fn: pointer to a callback function
621 *
622 * Call @fn for each registered clk_hw_omap, passing @hw to each
623 * function. @fn must return 0 for success or any other value for
624 * failure. If @fn returns non-zero, the iteration across clocks
625 * will stop and the non-zero return value will be passed to the
626 * caller of omap2_clk_for_each().
627 */
628int omap2_clk_for_each(int (*fn)(struct clk_hw_omap *hw))
629{
630 int ret;
631 struct clk_hw_omap *hw;
632
633 list_for_each_entry(hw, &clk_hw_omap_clocks, node) {
634 ret = (*fn)(hw);
635 if (ret)
636 break;
637 }
638
639 return ret;
640}
641
642/**
643 * omap2_clk_is_hw_omap - check if the provided clk_hw is OMAP clock
644 * @hw: clk_hw to check if it is an omap clock or not
645 *
646 * Checks if the provided clk_hw is OMAP clock or not. Returns true if
647 * it is, false otherwise.
648 */
649bool omap2_clk_is_hw_omap(struct clk_hw *hw)
650{
651 struct clk_hw_omap *oclk;
652
653 list_for_each_entry(oclk, &clk_hw_omap_clocks, node) {
654 if (&oclk->hw == hw)
655 return true;
656 }
657
658 return false;
659}
660

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