1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright 2012 Freescale Semiconductor, Inc.
  4 * Copyright 2012 Linaro Ltd.
  5 */
  6
  7#include <linux/bits.h>
  8#include <linux/clk.h>
  9#include <linux/clk-provider.h>
 10#include <linux/io.h>
 11#include <linux/slab.h>
 12#include <linux/jiffies.h>
 13#include <linux/err.h>
 14#include "clk.h"
 15
 16static int clk_busy_wait(void __iomem *reg, u8 shift)
 17{
 18	unsigned long timeout = jiffies + msecs_to_jiffies(10);
 19
 20	while (readl_relaxed(reg) & (1 << shift))
 21		if (time_after(jiffies, timeout))
 22			return -ETIMEDOUT;
 23
 24	return 0;
 25}
 26
 27struct clk_busy_divider {
 28	struct clk_divider div;
 29	const struct clk_ops *div_ops;
 30	void __iomem *reg;
 31	u8 shift;
 32};
 33
 34static inline struct clk_busy_divider *to_clk_busy_divider(struct clk_hw *hw)
 35{
 36	struct clk_divider *div = to_clk_divider(hw);
 37
 38	return container_of(div, struct clk_busy_divider, div);
 39}
 40
 41static unsigned long clk_busy_divider_recalc_rate(struct clk_hw *hw,
 42						  unsigned long parent_rate)
 43{
 44	struct clk_busy_divider *busy = to_clk_busy_divider(hw);
 45
 46	return busy->div_ops->recalc_rate(&busy->div.hw, parent_rate);
 47}
 48
 49static long clk_busy_divider_round_rate(struct clk_hw *hw, unsigned long rate,
 50					unsigned long *prate)
 51{
 52	struct clk_busy_divider *busy = to_clk_busy_divider(hw);
 53
 54	return busy->div_ops->round_rate(&busy->div.hw, rate, prate);
 55}
 56
 57static int clk_busy_divider_set_rate(struct clk_hw *hw, unsigned long rate,
 58		unsigned long parent_rate)
 59{
 60	struct clk_busy_divider *busy = to_clk_busy_divider(hw);
 61	int ret;
 62
 63	ret = busy->div_ops->set_rate(&busy->div.hw, rate, parent_rate);
 64	if (!ret)
 65		ret = clk_busy_wait(busy->reg, busy->shift);
 66
 67	return ret;
 68}
 69
 70static const struct clk_ops clk_busy_divider_ops = {
 71	.recalc_rate = clk_busy_divider_recalc_rate,
 72	.round_rate = clk_busy_divider_round_rate,
 73	.set_rate = clk_busy_divider_set_rate,
 74};
 75
 76struct clk_hw *imx_clk_hw_busy_divider(const char *name, const char *parent_name,
 77				 void __iomem *reg, u8 shift, u8 width,
 78				 void __iomem *busy_reg, u8 busy_shift)
 79{
 80	struct clk_busy_divider *busy;
 81	struct clk_hw *hw;
 82	struct clk_init_data init;
 83	int ret;
 84
 85	busy = kzalloc(sizeof(*busy), GFP_KERNEL);
 86	if (!busy)
 87		return ERR_PTR(-ENOMEM);
 88
 89	busy->reg = busy_reg;
 90	busy->shift = busy_shift;
 91
 92	busy->div.reg = reg;
 93	busy->div.shift = shift;
 94	busy->div.width = width;
 95	busy->div.lock = &imx_ccm_lock;
 96	busy->div_ops = &clk_divider_ops;
 97
 98	init.name = name;
 99	init.ops = &clk_busy_divider_ops;
100	init.flags = CLK_SET_RATE_PARENT | CLK_IS_CRITICAL;
101	init.parent_names = &parent_name;
102	init.num_parents = 1;
103
104	busy->div.hw.init = &init;
105
106	hw = &busy->div.hw;
107
108	ret = clk_hw_register(NULL, hw);
109	if (ret) {
110		kfree(busy);
111		return ERR_PTR(ret);
112	}
113
114	return hw;
115}
116
117struct clk_busy_mux {
118	struct clk_mux mux;
119	const struct clk_ops *mux_ops;
120	void __iomem *reg;
121	u8 shift;
122};
123
124static inline struct clk_busy_mux *to_clk_busy_mux(struct clk_hw *hw)
125{
126	struct clk_mux *mux = to_clk_mux(hw);
127
128	return container_of(mux, struct clk_busy_mux, mux);
129}
130
131static u8 clk_busy_mux_get_parent(struct clk_hw *hw)
132{
133	struct clk_busy_mux *busy = to_clk_busy_mux(hw);
134
135	return busy->mux_ops->get_parent(&busy->mux.hw);
136}
137
138static int clk_busy_mux_set_parent(struct clk_hw *hw, u8 index)
139{
140	struct clk_busy_mux *busy = to_clk_busy_mux(hw);
141	int ret;
142
143	ret = busy->mux_ops->set_parent(&busy->mux.hw, index);
144	if (!ret)
145		ret = clk_busy_wait(busy->reg, busy->shift);
146
147	return ret;
148}
149
150static const struct clk_ops clk_busy_mux_ops = {
151	.determine_rate = clk_hw_determine_rate_no_reparent,
152	.get_parent = clk_busy_mux_get_parent,
153	.set_parent = clk_busy_mux_set_parent,
154};
155
156struct clk_hw *imx_clk_hw_busy_mux(const char *name, void __iomem *reg, u8 shift,
157			     u8 width, void __iomem *busy_reg, u8 busy_shift,
158			     const char * const *parent_names, int num_parents)
159{
160	struct clk_busy_mux *busy;
161	struct clk_hw *hw;
162	struct clk_init_data init;
163	int ret;
164
165	busy = kzalloc(sizeof(*busy), GFP_KERNEL);
166	if (!busy)
167		return ERR_PTR(-ENOMEM);
168
169	busy->reg = busy_reg;
170	busy->shift = busy_shift;
171
172	busy->mux.reg = reg;
173	busy->mux.shift = shift;
174	busy->mux.mask = BIT(width) - 1;
175	busy->mux.lock = &imx_ccm_lock;
176	busy->mux_ops = &clk_mux_ops;
177
178	init.name = name;
179	init.ops = &clk_busy_mux_ops;
180	init.flags = CLK_IS_CRITICAL;
181	init.parent_names = parent_names;
182	init.num_parents = num_parents;
183
184	busy->mux.hw.init = &init;
185
186	hw = &busy->mux.hw;
187
188	ret = clk_hw_register(NULL, hw);
189	if (ret) {
190		kfree(busy);
191		return ERR_PTR(ret);
192	}
193
194	return hw;
195}