1/*
2 * TI clock support
3 *
4 * Copyright (C) 2013 Texas Instruments, Inc.
5 *
6 * Tero Kristo <t-kristo@ti.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
13 * kind, whether express or implied; without even the implied warranty
14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 */
17
18#include <linux/clk-provider.h>
19#include <linux/clkdev.h>
20#include <linux/clk/ti.h>
21#include <linux/of.h>
22#include <linux/of_address.h>
23#include <linux/list.h>
24
25#include "clock.h"
26
27#undef pr_fmt
28#define pr_fmt(fmt) "%s: " fmt, __func__
29
30struct ti_clk_ll_ops *ti_clk_ll_ops;
31static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS];
32
33/**
34 * ti_dt_clocks_register - register DT alias clocks during boot
35 * @oclks: list of clocks to register
36 *
37 * Register alias or non-standard DT clock entries during boot. By
38 * default, DT clocks are found based on their node name. If any
39 * additional con-id / dev-id -> clock mapping is required, use this
40 * function to list these.
41 */
42void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])
43{
44	struct ti_dt_clk *c;
45	struct device_node *node;
46	struct clk *clk;
47	struct of_phandle_args clkspec;
48
49	for (c = oclks; c->node_name != NULL; c++) {
50		node = of_find_node_by_name(NULL, c->node_name);
51		clkspec.np = node;
52		clk = of_clk_get_from_provider(&clkspec);
53
54		if (!IS_ERR(clk)) {
55			c->lk.clk = clk;
56			clkdev_add(&c->lk);
57		} else {
58			pr_warn("failed to lookup clock node %s\n",
59				c->node_name);
60		}
61	}
62}
63
64struct clk_init_item {
65	struct device_node *node;
66	struct clk_hw *hw;
67	ti_of_clk_init_cb_t func;
68	struct list_head link;
69};
70
71static LIST_HEAD(retry_list);
72
73/**
74 * ti_clk_retry_init - retries a failed clock init at later phase
75 * @node: device not for the clock
76 * @hw: partially initialized clk_hw struct for the clock
77 * @func: init function to be called for the clock
78 *
79 * Adds a failed clock init to the retry list. The retry list is parsed
80 * once all the other clocks have been initialized.
81 */
82int __init ti_clk_retry_init(struct device_node *node, struct clk_hw *hw,
83			      ti_of_clk_init_cb_t func)
84{
85	struct clk_init_item *retry;
86
87	pr_debug("%s: adding to retry list...\n", node->name);
88	retry = kzalloc(sizeof(*retry), GFP_KERNEL);
89	if (!retry)
90		return -ENOMEM;
91
92	retry->node = node;
93	retry->func = func;
94	retry->hw = hw;
95	list_add(&retry->link, &retry_list);
96
97	return 0;
98}
99
100/**
101 * ti_clk_get_reg_addr - get register address for a clock register
102 * @node: device node for the clock
103 * @index: register index from the clock node
104 *
105 * Builds clock register address from device tree information. This
106 * is a struct of type clk_omap_reg. Returns a pointer to the register
107 * address, or a pointer error value in failure.
108 */
109void __iomem *ti_clk_get_reg_addr(struct device_node *node, int index)
110{
111	struct clk_omap_reg *reg;
112	u32 val;
113	u32 tmp;
114	int i;
115
116	reg = (struct clk_omap_reg *)&tmp;
117
118	for (i = 0; i < CLK_MAX_MEMMAPS; i++) {
119		if (clocks_node_ptr[i] == node->parent)
120			break;
121	}
122
123	if (i == CLK_MAX_MEMMAPS) {
124		pr_err("clk-provider not found for %s!\n", node->name);
125		return ERR_PTR(-ENOENT);
126	}
127
128	reg->index = i;
129
130	if (of_property_read_u32_index(node, "reg", index, &val)) {
131		pr_err("%s must have reg[%d]!\n", node->name, index);
132		return ERR_PTR(-EINVAL);
133	}
134
135	reg->offset = val;
136
137	return (void __iomem *)tmp;
138}
139
140/**
141 * ti_dt_clk_init_provider - init master clock provider
142 * @parent: master node
143 * @index: internal index for clk_reg_ops
144 *
145 * Initializes a master clock IP block. This basically sets up the
146 * mapping from clocks node to the memory map index. All the clocks
147 * are then initialized through the common of_clk_init call, and the
148 * clocks will access their memory maps based on the node layout.
149 */
150void ti_dt_clk_init_provider(struct device_node *parent, int index)
151{
152	struct device_node *clocks;
153
154	/* get clocks for this parent */
155	clocks = of_get_child_by_name(parent, "clocks");
156	if (!clocks) {
157		pr_err("%s missing 'clocks' child node.\n", parent->name);
158		return;
159	}
160
161	/* add clocks node info */
162	clocks_node_ptr[index] = clocks;
163}
164
165/**
166 * ti_dt_clk_init_retry_clks - init clocks from the retry list
167 *
168 * Initializes any clocks that have failed to initialize before,
169 * reasons being missing parent node(s) during earlier init. This
170 * typically happens only for DPLLs which need to have both of their
171 * parent clocks ready during init.
172 */
173void ti_dt_clk_init_retry_clks(void)
174{
175	struct clk_init_item *retry;
176	struct clk_init_item *tmp;
177	int retries = 5;
178
179	while (!list_empty(&retry_list) && retries) {
180		list_for_each_entry_safe(retry, tmp, &retry_list, link) {
181			pr_debug("retry-init: %s\n", retry->node->name);
182			retry->func(retry->hw, retry->node);
183			list_del(&retry->link);
184			kfree(retry);
185		}
186		retries--;
187	}
188}
189
190#if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_ATAGS)
191void __init ti_clk_patch_legacy_clks(struct ti_clk **patch)
192{
193	while (*patch) {
194		memcpy((*patch)->patch, *patch, sizeof(**patch));
195		patch++;
196	}
197}
198
199struct clk __init *ti_clk_register_clk(struct ti_clk *setup)
200{
201	struct clk *clk;
202	struct ti_clk_fixed *fixed;
203	struct ti_clk_fixed_factor *fixed_factor;
204	struct clk_hw *clk_hw;
205
206	if (setup->clk)
207		return setup->clk;
208
209	switch (setup->type) {
210	case TI_CLK_FIXED:
211		fixed = setup->data;
212
213		clk = clk_register_fixed_rate(NULL, setup->name, NULL,
214					      CLK_IS_ROOT, fixed->frequency);
215		break;
216	case TI_CLK_MUX:
217		clk = ti_clk_register_mux(setup);
218		break;
219	case TI_CLK_DIVIDER:
220		clk = ti_clk_register_divider(setup);
221		break;
222	case TI_CLK_COMPOSITE:
223		clk = ti_clk_register_composite(setup);
224		break;
225	case TI_CLK_FIXED_FACTOR:
226		fixed_factor = setup->data;
227
228		clk = clk_register_fixed_factor(NULL, setup->name,
229						fixed_factor->parent,
230						0, fixed_factor->mult,
231						fixed_factor->div);
232		break;
233	case TI_CLK_GATE:
234		clk = ti_clk_register_gate(setup);
235		break;
236	case TI_CLK_DPLL:
237		clk = ti_clk_register_dpll(setup);
238		break;
239	default:
240		pr_err("bad type for %s!\n", setup->name);
241		clk = ERR_PTR(-EINVAL);
242	}
243
244	if (!IS_ERR(clk)) {
245		setup->clk = clk;
246		if (setup->clkdm_name) {
247			if (__clk_get_flags(clk) & CLK_IS_BASIC) {
248				pr_warn("can't setup clkdm for basic clk %s\n",
249					setup->name);
250			} else {
251				clk_hw = __clk_get_hw(clk);
252				to_clk_hw_omap(clk_hw)->clkdm_name =
253					setup->clkdm_name;
254				omap2_init_clk_clkdm(clk_hw);
255			}
256		}
257	}
258
259	return clk;
260}
261
262int __init ti_clk_register_legacy_clks(struct ti_clk_alias *clks)
263{
264	struct clk *clk;
265	bool retry;
266	struct ti_clk_alias *retry_clk;
267	struct ti_clk_alias *tmp;
268
269	while (clks->clk) {
270		clk = ti_clk_register_clk(clks->clk);
271		if (IS_ERR(clk)) {
272			if (PTR_ERR(clk) == -EAGAIN) {
273				list_add(&clks->link, &retry_list);
274			} else {
275				pr_err("register for %s failed: %ld\n",
276				       clks->clk->name, PTR_ERR(clk));
277				return PTR_ERR(clk);
278			}
279		} else {
280			clks->lk.clk = clk;
281			clkdev_add(&clks->lk);
282		}
283		clks++;
284	}
285
286	retry = true;
287
288	while (!list_empty(&retry_list) && retry) {
289		retry = false;
290		list_for_each_entry_safe(retry_clk, tmp, &retry_list, link) {
291			pr_debug("retry-init: %s\n", retry_clk->clk->name);
292			clk = ti_clk_register_clk(retry_clk->clk);
293			if (IS_ERR(clk)) {
294				if (PTR_ERR(clk) == -EAGAIN) {
295					continue;
296				} else {
297					pr_err("register for %s failed: %ld\n",
298					       retry_clk->clk->name,
299					       PTR_ERR(clk));
300					return PTR_ERR(clk);
301				}
302			} else {
303				retry = true;
304				retry_clk->lk.clk = clk;
305				clkdev_add(&retry_clk->lk);
306				list_del(&retry_clk->link);
307			}
308		}
309	}
310
311	return 0;
312}
313#endif
314