[linux-2.6-block.git] / drivers / clk / rockchip / clk-cpu.c

/*
 * Copyright (c) 2014 MundoReader S.L.
 * Author: Heiko Stuebner <heiko@sntech.de>
 *
 * based on clk/samsung/clk-cpu.c
 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
 * Author: Thomas Abraham <thomas.ab@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * A CPU clock is defined as a clock supplied to a CPU or a group of CPUs.
 * The CPU clock is typically derived from a hierarchy of clock
 * blocks which includes mux and divider blocks. There are a number of other
 * auxiliary clocks supplied to the CPU domain such as the debug blocks and AXI
 * clock for CPU domain. The rates of these auxiliary clocks are related to the
 * CPU clock rate and this relation is usually specified in the hardware manual
 * of the SoC or supplied after the SoC characterization.
 *
 * The below implementation of the CPU clock allows the rate changes of the CPU
 * clock and the corresponding rate changes of the auxillary clocks of the CPU
 * domain. The platform clock driver provides a clock register configuration
 * for each configurable rate which is then used to program the clock hardware
 * registers to acheive a fast co-oridinated rate change for all the CPU domain
 * clocks.
 *
 * On a rate change request for the CPU clock, the rate change is propagated
 * upto the PLL supplying the clock to the CPU domain clock blocks. While the
 * CPU domain PLL is reconfigured, the CPU domain clocks are driven using an
 * alternate clock source. If required, the alternate clock source is divided
 * down in order to keep the output clock rate within the previous OPP limits.
 */

#include <linux/of.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/clk-provider.h>
#include "clk.h"

/**
 * struct rockchip_cpuclk: information about clock supplied to a CPU core.
 * @hw:		handle between ccf and cpu clock.
 * @alt_parent:	alternate parent clock to use when switching the speed
 *		of the primary parent clock.
 * @reg_base:	base register for cpu-clock values.
 * @clk_nb:	clock notifier registered for changes in clock speed of the
 *		primary parent clock.
 * @rate_count:	number of rates in the rate_table
 * @rate_table:	pll-rates and their associated dividers
 * @reg_data:	cpu-specific register settings
 * @lock:	clock lock
 */
struct rockchip_cpuclk {
	struct clk_hw				hw;

	struct clk_mux				cpu_mux;
	const struct clk_ops			*cpu_mux_ops;

	struct clk				*alt_parent;
	void __iomem				*reg_base;
	struct notifier_block			clk_nb;
	unsigned int				rate_count;
	struct rockchip_cpuclk_rate_table	*rate_table;
	const struct rockchip_cpuclk_reg_data	*reg_data;
	spinlock_t				*lock;
};

#define to_rockchip_cpuclk_hw(hw) container_of(hw, struct rockchip_cpuclk, hw)
#define to_rockchip_cpuclk_nb(nb) \
			container_of(nb, struct rockchip_cpuclk, clk_nb)

static const struct rockchip_cpuclk_rate_table *rockchip_get_cpuclk_settings(
			    struct rockchip_cpuclk *cpuclk, unsigned long rate)
{
	const struct rockchip_cpuclk_rate_table *rate_table =
							cpuclk->rate_table;
	int i;

	for (i = 0; i < cpuclk->rate_count; i++) {
		if (rate == rate_table[i].prate)
			return &rate_table[i];
	}

	return NULL;
}

static unsigned long rockchip_cpuclk_recalc_rate(struct clk_hw *hw,
					unsigned long parent_rate)
{
	struct rockchip_cpuclk *cpuclk = to_rockchip_cpuclk_hw(hw);
	const struct rockchip_cpuclk_reg_data *reg_data = cpuclk->reg_data;
	u32 clksel0 = readl_relaxed(cpuclk->reg_base + reg_data->core_reg);

	clksel0 >>= reg_data->div_core_shift;
	clksel0 &= reg_data->div_core_mask;
	return parent_rate / (clksel0 + 1);
}

static const struct clk_ops rockchip_cpuclk_ops = {
	.recalc_rate = rockchip_cpuclk_recalc_rate,
};

static void rockchip_cpuclk_set_dividers(struct rockchip_cpuclk *cpuclk,
				const struct rockchip_cpuclk_rate_table *rate)
{
	int i;

	/* alternate parent is active now. set the dividers */
	for (i = 0; i < ARRAY_SIZE(rate->divs); i++) {
		const struct rockchip_cpuclk_clksel *clksel = &rate->divs[i];

		if (!clksel->reg)
			continue;

		pr_debug("%s: setting reg 0x%x to 0x%x\n",
			 __func__, clksel->reg, clksel->val);
		writel(clksel->val , cpuclk->reg_base + clksel->reg);
	}
}

static int rockchip_cpuclk_pre_rate_change(struct rockchip_cpuclk *cpuclk,
					   struct clk_notifier_data *ndata)
{
	const struct rockchip_cpuclk_reg_data *reg_data = cpuclk->reg_data;
	unsigned long alt_prate, alt_div;
	unsigned long flags;

	alt_prate = clk_get_rate(cpuclk->alt_parent);

	spin_lock_irqsave(cpuclk->lock, flags);

	/*
	 * If the old parent clock speed is less than the clock speed
	 * of the alternate parent, then it should be ensured that at no point
	 * the armclk speed is more than the old_rate until the dividers are
	 * set.
	 */
	if (alt_prate > ndata->old_rate) {
		/* calculate dividers */
		alt_div =  DIV_ROUND_UP(alt_prate, ndata->old_rate) - 1;
		if (alt_div > reg_data->div_core_mask) {
			pr_warn("%s: limiting alt-divider %lu to %d\n",
				__func__, alt_div, reg_data->div_core_mask);
			alt_div = reg_data->div_core_mask;
		}

		/*
		 * Change parents and add dividers in a single transaction.
		 *
		 * NOTE: we do this in a single transaction so we're never
		 * dividing the primary parent by the extra dividers that were
		 * needed for the alt.
		 */
		pr_debug("%s: setting div %lu as alt-rate %lu > old-rate %lu\n",
			 __func__, alt_div, alt_prate, ndata->old_rate);

		writel(HIWORD_UPDATE(alt_div, reg_data->div_core_mask,
					      reg_data->div_core_shift) |
		       HIWORD_UPDATE(1, 1, reg_data->mux_core_shift),
		       cpuclk->reg_base + reg_data->core_reg);
	} else {
		/* select alternate parent */
		writel(HIWORD_UPDATE(1, 1, reg_data->mux_core_shift),
			cpuclk->reg_base + reg_data->core_reg);
	}

	spin_unlock_irqrestore(cpuclk->lock, flags);
	return 0;
}

static int rockchip_cpuclk_post_rate_change(struct rockchip_cpuclk *cpuclk,
					    struct clk_notifier_data *ndata)
{
	const struct rockchip_cpuclk_reg_data *reg_data = cpuclk->reg_data;
	const struct rockchip_cpuclk_rate_table *rate;
	unsigned long flags;

	rate = rockchip_get_cpuclk_settings(cpuclk, ndata->new_rate);
	if (!rate) {
		pr_err("%s: Invalid rate : %lu for cpuclk\n",
		       __func__, ndata->new_rate);
		return -EINVAL;
	}

	spin_lock_irqsave(cpuclk->lock, flags);

	if (ndata->old_rate < ndata->new_rate)
		rockchip_cpuclk_set_dividers(cpuclk, rate);

	/*
	 * post-rate change event, re-mux to primary parent and remove dividers.
	 *
	 * NOTE: we do this in a single transaction so we're never dividing the
	 * primary parent by the extra dividers that were needed for the alt.
	 */

	writel(HIWORD_UPDATE(0, reg_data->div_core_mask,
				reg_data->div_core_shift) |
	       HIWORD_UPDATE(0, 1, reg_data->mux_core_shift),
	       cpuclk->reg_base + reg_data->core_reg);

	if (ndata->old_rate > ndata->new_rate)
		rockchip_cpuclk_set_dividers(cpuclk, rate);

	spin_unlock_irqrestore(cpuclk->lock, flags);
	return 0;
}

/*
 * This clock notifier is called when the frequency of the parent clock
 * of cpuclk is to be changed. This notifier handles the setting up all
 * the divider clocks, remux to temporary parent and handling the safe
 * frequency levels when using temporary parent.
 */
static int rockchip_cpuclk_notifier_cb(struct notifier_block *nb,
					unsigned long event, void *data)
{
	struct clk_notifier_data *ndata = data;
	struct rockchip_cpuclk *cpuclk = to_rockchip_cpuclk_nb(nb);
	int ret = 0;

	pr_debug("%s: event %lu, old_rate %lu, new_rate: %lu\n",
		 __func__, event, ndata->old_rate, ndata->new_rate);
	if (event == PRE_RATE_CHANGE)
		ret = rockchip_cpuclk_pre_rate_change(cpuclk, ndata);
	else if (event == POST_RATE_CHANGE)
		ret = rockchip_cpuclk_post_rate_change(cpuclk, ndata);

	return notifier_from_errno(ret);
}

struct clk *rockchip_clk_register_cpuclk(const char *name,
			const char **parent_names, u8 num_parents,
			const struct rockchip_cpuclk_reg_data *reg_data,
			const struct rockchip_cpuclk_rate_table *rates,
			int nrates, void __iomem *reg_base, spinlock_t *lock)
{
	struct rockchip_cpuclk *cpuclk;
	struct clk_init_data init;
	struct clk *clk, *cclk;
	int ret;

	if (num_parents != 2) {
		pr_err("%s: needs two parent clocks\n", __func__);
		return ERR_PTR(-EINVAL);
	}

	cpuclk = kzalloc(sizeof(*cpuclk), GFP_KERNEL);
	if (!cpuclk)
		return ERR_PTR(-ENOMEM);

	init.name = name;
	init.parent_names = &parent_names[0];
	init.num_parents = 1;
	init.ops = &rockchip_cpuclk_ops;

	/* only allow rate changes when we have a rate table */
	init.flags = (nrates > 0) ? CLK_SET_RATE_PARENT : 0;

	/* disallow automatic parent changes by ccf */
	init.flags |= CLK_SET_RATE_NO_REPARENT;

	init.flags |= CLK_GET_RATE_NOCACHE;

	cpuclk->reg_base = reg_base;
	cpuclk->lock = lock;
	cpuclk->reg_data = reg_data;
	cpuclk->clk_nb.notifier_call = rockchip_cpuclk_notifier_cb;
	cpuclk->hw.init = &init;

	cpuclk->alt_parent = __clk_lookup(parent_names[1]);
	if (!cpuclk->alt_parent) {
		pr_err("%s: could not lookup alternate parent\n",
		       __func__);
		ret = -EINVAL;
		goto free_cpuclk;
	}

	ret = clk_prepare_enable(cpuclk->alt_parent);
	if (ret) {
		pr_err("%s: could not enable alternate parent\n",
		       __func__);
		goto free_cpuclk;
	}

	clk = __clk_lookup(parent_names[0]);
	if (!clk) {
		pr_err("%s: could not lookup parent clock %s\n",
		       __func__, parent_names[0]);
		ret = -EINVAL;
		goto free_cpuclk;
	}

	ret = clk_notifier_register(clk, &cpuclk->clk_nb);
	if (ret) {
		pr_err("%s: failed to register clock notifier for %s\n",
				__func__, name);
		goto free_cpuclk;
	}

	if (nrates > 0) {
		cpuclk->rate_count = nrates;
		cpuclk->rate_table = kmemdup(rates,
					     sizeof(*rates) * nrates,
					     GFP_KERNEL);
		if (!cpuclk->rate_table) {
			pr_err("%s: could not allocate memory for cpuclk rates\n",
			       __func__);
			ret = -ENOMEM;
			goto unregister_notifier;
		}
	}

	cclk = clk_register(NULL, &cpuclk->hw);
	if (IS_ERR(clk)) {
		pr_err("%s: could not register cpuclk %s\n", __func__,	name);
		ret = PTR_ERR(clk);
		goto free_rate_table;
	}

	return cclk;

free_rate_table:
	kfree(cpuclk->rate_table);
unregister_notifier:
	clk_notifier_unregister(clk, &cpuclk->clk_nb);
free_cpuclk:
	kfree(cpuclk);
	return ERR_PTR(ret);
}
Commit	Line	Data
f6fba5f6 HS	1	/*
	2	* Copyright (c) 2014 MundoReader S.L.
	3	* Author: Heiko Stuebner <heiko@sntech.de>
	4	*
	5	* based on clk/samsung/clk-cpu.c
	6	* Copyright (c) 2014 Samsung Electronics Co., Ltd.
	7	* Author: Thomas Abraham <thomas.ab@samsung.com>
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*
	13	* A CPU clock is defined as a clock supplied to a CPU or a group of CPUs.
	14	* The CPU clock is typically derived from a hierarchy of clock
	15	* blocks which includes mux and divider blocks. There are a number of other
	16	* auxiliary clocks supplied to the CPU domain such as the debug blocks and AXI
	17	* clock for CPU domain. The rates of these auxiliary clocks are related to the
	18	* CPU clock rate and this relation is usually specified in the hardware manual
	19	* of the SoC or supplied after the SoC characterization.
	20	*
	21	* The below implementation of the CPU clock allows the rate changes of the CPU
	22	* clock and the corresponding rate changes of the auxillary clocks of the CPU
	23	* domain. The platform clock driver provides a clock register configuration
	24	* for each configurable rate which is then used to program the clock hardware
	25	* registers to acheive a fast co-oridinated rate change for all the CPU domain
	26	* clocks.
	27	*
	28	* On a rate change request for the CPU clock, the rate change is propagated
	29	* upto the PLL supplying the clock to the CPU domain clock blocks. While the
	30	* CPU domain PLL is reconfigured, the CPU domain clocks are driven using an
	31	* alternate clock source. If required, the alternate clock source is divided
	32	* down in order to keep the output clock rate within the previous OPP limits.
	33	*/
	34
	35	#include <linux/of.h>
	36	#include <linux/slab.h>
	37	#include <linux/io.h>
	38	#include <linux/clk-provider.h>
	39	#include "clk.h"
	40
	41	/**
	42	* struct rockchip_cpuclk: information about clock supplied to a CPU core.
	43	* @hw: handle between ccf and cpu clock.
	44	* @alt_parent: alternate parent clock to use when switching the speed
	45	* of the primary parent clock.
	46	* @reg_base: base register for cpu-clock values.
	47	* @clk_nb: clock notifier registered for changes in clock speed of the
	48	* primary parent clock.
	49	* @rate_count: number of rates in the rate_table
	50	* @rate_table: pll-rates and their associated dividers
	51	* @reg_data: cpu-specific register settings
	52	* @lock: clock lock
	53	*/
	54	struct rockchip_cpuclk {
	55	struct clk_hw hw;
	56
	57	struct clk_mux cpu_mux;
	58	const struct clk_ops *cpu_mux_ops;
	59
	60	struct clk *alt_parent;
	61	void __iomem *reg_base;
	62	struct notifier_block clk_nb;
	63	unsigned int rate_count;
	64	struct rockchip_cpuclk_rate_table *rate_table;
65	const struct rockchip_cpuclk_reg_data *reg_data;
66	spinlock_t *lock;
67	};
68
69	#define to_rockchip_cpuclk_hw(hw) container_of(hw, struct rockchip_cpuclk, hw)
70	#define to_rockchip_cpuclk_nb(nb) \
71	container_of(nb, struct rockchip_cpuclk, clk_nb)
72
73	static const struct rockchip_cpuclk_rate_table *rockchip_get_cpuclk_settings(
74	struct rockchip_cpuclk *cpuclk, unsigned long rate)
75	{
76	const struct rockchip_cpuclk_rate_table *rate_table =
77	cpuclk->rate_table;
78	int i;
79
80	for (i = 0; i < cpuclk->rate_count; i++) {
81	if (rate == rate_table[i].prate)
82	return &rate_table[i];
83	}
84
85	return NULL;
86	}
87
88	static unsigned long rockchip_cpuclk_recalc_rate(struct clk_hw *hw,
89	unsigned long parent_rate)
90	{
91	struct rockchip_cpuclk *cpuclk = to_rockchip_cpuclk_hw(hw);
92	const struct rockchip_cpuclk_reg_data *reg_data = cpuclk->reg_data;
93	u32 clksel0 = readl_relaxed(cpuclk->reg_base + reg_data->core_reg);
94
95	clksel0 >>= reg_data->div_core_shift;
96	clksel0 &= reg_data->div_core_mask;
97	return parent_rate / (clksel0 + 1);
98	}
99
100	static const struct clk_ops rockchip_cpuclk_ops = {
101	.recalc_rate = rockchip_cpuclk_recalc_rate,
102	};
103
104	static void rockchip_cpuclk_set_dividers(struct rockchip_cpuclk *cpuclk,
105	const struct rockchip_cpuclk_rate_table *rate)
106	{
107	int i;
108
109	/* alternate parent is active now. set the dividers */
110	for (i = 0; i < ARRAY_SIZE(rate->divs); i++) {
111	const struct rockchip_cpuclk_clksel *clksel = &rate->divs[i];
112
113	if (!clksel->reg)
114	continue;
115
116	pr_debug("%s: setting reg 0x%x to 0x%x\n",
117	__func__, clksel->reg, clksel->val);
118	writel(clksel->val , cpuclk->reg_base + clksel->reg);
119	}
120	}
121
122	static int rockchip_cpuclk_pre_rate_change(struct rockchip_cpuclk *cpuclk,
123	struct clk_notifier_data *ndata)
124	{
125	const struct rockchip_cpuclk_reg_data *reg_data = cpuclk->reg_data;
126	unsigned long alt_prate, alt_div;
a5e1baf7	127	unsigned long flags;
f6fba5f6 HS	128
	129	alt_prate = clk_get_rate(cpuclk->alt_parent);
	130
a5e1baf7	131	spin_lock_irqsave(cpuclk->lock, flags);
f6fba5f6 HS	132
	133	/*
	134	* If the old parent clock speed is less than the clock speed
	135	* of the alternate parent, then it should be ensured that at no point
	136	* the armclk speed is more than the old_rate until the dividers are
	137	* set.
	138	*/
	139	if (alt_prate > ndata->old_rate) {
	140	/* calculate dividers */
	141	alt_div = DIV_ROUND_UP(alt_prate, ndata->old_rate) - 1;
	142	if (alt_div > reg_data->div_core_mask) {
	143	pr_warn("%s: limiting alt-divider %lu to %d\n",
	144	__func__, alt_div, reg_data->div_core_mask);
	145	alt_div = reg_data->div_core_mask;
	146	}
	147
	148	/*
	149	* Change parents and add dividers in a single transaction.
	150	*
	151	* NOTE: we do this in a single transaction so we're never
	152	* dividing the primary parent by the extra dividers that were
	153	* needed for the alt.
	154	*/
	155	pr_debug("%s: setting div %lu as alt-rate %lu > old-rate %lu\n",
	156	__func__, alt_div, alt_prate, ndata->old_rate);
	157
	158	writel(HIWORD_UPDATE(alt_div, reg_data->div_core_mask,
	159	reg_data->div_core_shift) \|
	160	HIWORD_UPDATE(1, 1, reg_data->mux_core_shift),
	161	cpuclk->reg_base + reg_data->core_reg);
	162	} else {
	163	/* select alternate parent */
	164	writel(HIWORD_UPDATE(1, 1, reg_data->mux_core_shift),
	165	cpuclk->reg_base + reg_data->core_reg);
	166	}
	167
a5e1baf7	168	spin_unlock_irqrestore(cpuclk->lock, flags);
f6fba5f6 HS	169	return 0;
	170	}
	171
	172	static int rockchip_cpuclk_post_rate_change(struct rockchip_cpuclk *cpuclk,
	173	struct clk_notifier_data *ndata)
	174	{
	175	const struct rockchip_cpuclk_reg_data *reg_data = cpuclk->reg_data;
	176	const struct rockchip_cpuclk_rate_table *rate;
a5e1baf7	177	unsigned long flags;
f6fba5f6 HS	178
	179	rate = rockchip_get_cpuclk_settings(cpuclk, ndata->new_rate);
	180	if (!rate) {
	181	pr_err("%s: Invalid rate : %lu for cpuclk\n",
	182	__func__, ndata->new_rate);
	183	return -EINVAL;
	184	}
	185
a5e1baf7	186	spin_lock_irqsave(cpuclk->lock, flags);
f6fba5f6 HS	187
	188	if (ndata->old_rate < ndata->new_rate)
	189	rockchip_cpuclk_set_dividers(cpuclk, rate);
	190
	191	/*
	192	* post-rate change event, re-mux to primary parent and remove dividers.
	193	*
	194	* NOTE: we do this in a single transaction so we're never dividing the
	195	* primary parent by the extra dividers that were needed for the alt.
	196	*/
	197
	198	writel(HIWORD_UPDATE(0, reg_data->div_core_mask,
	199	reg_data->div_core_shift) \|
	200	HIWORD_UPDATE(0, 1, reg_data->mux_core_shift),
	201	cpuclk->reg_base + reg_data->core_reg);
	202
	203	if (ndata->old_rate > ndata->new_rate)
	204	rockchip_cpuclk_set_dividers(cpuclk, rate);
	205
a5e1baf7	206	spin_unlock_irqrestore(cpuclk->lock, flags);
f6fba5f6 HS	207	return 0;
	208	}
	209
	210	/*
	211	* This clock notifier is called when the frequency of the parent clock
	212	* of cpuclk is to be changed. This notifier handles the setting up all
	213	* the divider clocks, remux to temporary parent and handling the safe
	214	* frequency levels when using temporary parent.
	215	*/
	216	static int rockchip_cpuclk_notifier_cb(struct notifier_block *nb,
	217	unsigned long event, void *data)
	218	{
	219	struct clk_notifier_data *ndata = data;
	220	struct rockchip_cpuclk *cpuclk = to_rockchip_cpuclk_nb(nb);
	221	int ret = 0;
	222
	223	pr_debug("%s: event %lu, old_rate %lu, new_rate: %lu\n",
	224	__func__, event, ndata->old_rate, ndata->new_rate);
	225	if (event == PRE_RATE_CHANGE)
	226	ret = rockchip_cpuclk_pre_rate_change(cpuclk, ndata);
	227	else if (event == POST_RATE_CHANGE)
	228	ret = rockchip_cpuclk_post_rate_change(cpuclk, ndata);
	229
	230	return notifier_from_errno(ret);
	231	}
	232
	233	struct clk rockchip_clk_register_cpuclk(const char name,
	234	const char **parent_names, u8 num_parents,
	235	const struct rockchip_cpuclk_reg_data *reg_data,
	236	const struct rockchip_cpuclk_rate_table *rates,
	237	int nrates, void __iomem reg_base, spinlock_t lock)
	238	{
	239	struct rockchip_cpuclk *cpuclk;
	240	struct clk_init_data init;
	241	struct clk clk, cclk;
	242	int ret;
	243
	244	if (num_parents != 2) {
	245	pr_err("%s: needs two parent clocks\n", __func__);
	246	return ERR_PTR(-EINVAL);
	247	}
	248
	249	cpuclk = kzalloc(sizeof(*cpuclk), GFP_KERNEL);
	250	if (!cpuclk)
	251	return ERR_PTR(-ENOMEM);
	252
	253	init.name = name;
	254	init.parent_names = &parent_names[0];
	255	init.num_parents = 1;
	256	init.ops = &rockchip_cpuclk_ops;
	257
	258	/* only allow rate changes when we have a rate table */
	259	init.flags = (nrates > 0) ? CLK_SET_RATE_PARENT : 0;
	260
	261	/* disallow automatic parent changes by ccf */
	262	init.flags \|= CLK_SET_RATE_NO_REPARENT;
	263
	264	init.flags \|= CLK_GET_RATE_NOCACHE;
	265
	266	cpuclk->reg_base = reg_base;
	267	cpuclk->lock = lock;
	268	cpuclk->reg_data = reg_data;
	269	cpuclk->clk_nb.notifier_call = rockchip_cpuclk_notifier_cb;
	270	cpuclk->hw.init = &init;
271
272	cpuclk->alt_parent = __clk_lookup(parent_names[1]);
273	if (!cpuclk->alt_parent) {
274	pr_err("%s: could not lookup alternate parent\n",
275	__func__);
276	ret = -EINVAL;
277	goto free_cpuclk;
278	}
279
280	ret = clk_prepare_enable(cpuclk->alt_parent);
281	if (ret) {
282	pr_err("%s: could not enable alternate parent\n",
283	__func__);
284	goto free_cpuclk;
285	}
286
287	clk = __clk_lookup(parent_names[0]);
288	if (!clk) {
289	pr_err("%s: could not lookup parent clock %s\n",
290	__func__, parent_names[0]);
291	ret = -EINVAL;
292	goto free_cpuclk;
293	}
294
295	ret = clk_notifier_register(clk, &cpuclk->clk_nb);
296	if (ret) {
297	pr_err("%s: failed to register clock notifier for %s\n",
298	__func__, name);
299	goto free_cpuclk;
300	}
301
302	if (nrates > 0) {
303	cpuclk->rate_count = nrates;
304	cpuclk->rate_table = kmemdup(rates,
305	sizeof(rates) nrates,
306	GFP_KERNEL);
307	if (!cpuclk->rate_table) {
308	pr_err("%s: could not allocate memory for cpuclk rates\n",
309	__func__);
310	ret = -ENOMEM;
311	goto unregister_notifier;
312	}
313	}
314
315	cclk = clk_register(NULL, &cpuclk->hw);
316	if (IS_ERR(clk)) {
317	pr_err("%s: could not register cpuclk %s\n", __func__, name);
318	ret = PTR_ERR(clk);
319	goto free_rate_table;
320	}
321
322	return cclk;
323
324	free_rate_table:
325	kfree(cpuclk->rate_table);
326	unregister_notifier:
327	clk_notifier_unregister(clk, &cpuclk->clk_nb);
328	free_cpuclk:
329	kfree(cpuclk);
330	return ERR_PTR(ret);
331	}