[GitHub/exynos8895/android_kernel_samsung_universal8895.git] / drivers / clk / qcom / clk-pll.c

/*
 * Copyright (c) 2013, The Linux Foundation. All rights reserved.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/bug.h>
#include <linux/delay.h>
#include <linux/export.h>
#include <linux/clk-provider.h>
#include <linux/regmap.h>

#include <asm/div64.h>

#include "clk-pll.h"

#define PLL_OUTCTRL		BIT(0)
#define PLL_BYPASSNL		BIT(1)
#define PLL_RESET_N		BIT(2)
#define PLL_LOCK_COUNT_SHIFT	8
#define PLL_LOCK_COUNT_MASK	0x3f
#define PLL_BIAS_COUNT_SHIFT	14
#define PLL_BIAS_COUNT_MASK	0x3f
#define PLL_VOTE_FSM_ENA	BIT(20)
#define PLL_VOTE_FSM_RESET	BIT(21)

static int clk_pll_enable(struct clk_hw *hw)
{
	struct clk_pll *pll = to_clk_pll(hw);
	int ret;
	u32 mask, val;

	mask = PLL_OUTCTRL | PLL_RESET_N | PLL_BYPASSNL;
	ret = regmap_read(pll->clkr.regmap, pll->mode_reg, &val);
	if (ret)
		return ret;

	/* Skip if already enabled or in FSM mode */
	if ((val & mask) == mask || val & PLL_VOTE_FSM_ENA)
		return 0;

	/* Disable PLL bypass mode. */
	ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_BYPASSNL,
				 PLL_BYPASSNL);
	if (ret)
		return ret;

	/*
	 * H/W requires a 5us delay between disabling the bypass and
	 * de-asserting the reset. Delay 10us just to be safe.
	 */
	udelay(10);

	/* De-assert active-low PLL reset. */
	ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_RESET_N,
				 PLL_RESET_N);
	if (ret)
		return ret;

	/* Wait until PLL is locked. */
	udelay(50);

	/* Enable PLL output. */
	return regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_OUTCTRL,
				 PLL_OUTCTRL);
}

static void clk_pll_disable(struct clk_hw *hw)
{
	struct clk_pll *pll = to_clk_pll(hw);
	u32 mask;
	u32 val;

	regmap_read(pll->clkr.regmap, pll->mode_reg, &val);
	/* Skip if in FSM mode */
	if (val & PLL_VOTE_FSM_ENA)
		return;
	mask = PLL_OUTCTRL | PLL_RESET_N | PLL_BYPASSNL;
	regmap_update_bits(pll->clkr.regmap, pll->mode_reg, mask, 0);
}

static unsigned long
clk_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
{
	struct clk_pll *pll = to_clk_pll(hw);
	u32 l, m, n, config;
	unsigned long rate;
	u64 tmp;

	regmap_read(pll->clkr.regmap, pll->l_reg, &l);
	regmap_read(pll->clkr.regmap, pll->m_reg, &m);
	regmap_read(pll->clkr.regmap, pll->n_reg, &n);

	l &= 0x3ff;
	m &= 0x7ffff;
	n &= 0x7ffff;

	rate = parent_rate * l;
	if (n) {
		tmp = parent_rate;
		tmp *= m;
		do_div(tmp, n);
		rate += tmp;
	}
	if (pll->post_div_width) {
		regmap_read(pll->clkr.regmap, pll->config_reg, &config);
		config >>= pll->post_div_shift;
		config &= BIT(pll->post_div_width) - 1;
		rate /= config + 1;
	}

	return rate;
}

static const
struct pll_freq_tbl *find_freq(const struct pll_freq_tbl *f, unsigned long rate)
{
	if (!f)
		return NULL;

	for (; f->freq; f++)
		if (rate <= f->freq)
			return f;

	return NULL;
}

static int
clk_pll_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
{
	struct clk *parent = __clk_get_parent(hw->clk);
	struct clk_pll *pll = to_clk_pll(hw);
	const struct pll_freq_tbl *f;

	req->best_parent_hw = __clk_get_hw(parent);
	req->best_parent_rate = __clk_get_rate(parent);

	f = find_freq(pll->freq_tbl, req->rate);
	if (!f)
		req->rate = clk_pll_recalc_rate(hw, req->best_parent_rate);
	else
		req->rate = f->freq;

	return 0;
}

static int
clk_pll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long p_rate)
{
	struct clk_pll *pll = to_clk_pll(hw);
	const struct pll_freq_tbl *f;
	bool enabled;
	u32 mode;
	u32 enable_mask = PLL_OUTCTRL | PLL_BYPASSNL | PLL_RESET_N;

	f = find_freq(pll->freq_tbl, rate);
	if (!f)
		return -EINVAL;

	regmap_read(pll->clkr.regmap, pll->mode_reg, &mode);
	enabled = (mode & enable_mask) == enable_mask;

	if (enabled)
		clk_pll_disable(hw);

	regmap_update_bits(pll->clkr.regmap, pll->l_reg, 0x3ff, f->l);
	regmap_update_bits(pll->clkr.regmap, pll->m_reg, 0x7ffff, f->m);
	regmap_update_bits(pll->clkr.regmap, pll->n_reg, 0x7ffff, f->n);
	regmap_write(pll->clkr.regmap, pll->config_reg, f->ibits);

	if (enabled)
		clk_pll_enable(hw);

	return 0;
}

const struct clk_ops clk_pll_ops = {
	.enable = clk_pll_enable,
	.disable = clk_pll_disable,
	.recalc_rate = clk_pll_recalc_rate,
	.determine_rate = clk_pll_determine_rate,
	.set_rate = clk_pll_set_rate,
};
EXPORT_SYMBOL_GPL(clk_pll_ops);

static int wait_for_pll(struct clk_pll *pll)
{
	u32 val;
	int count;
	int ret;
	const char *name = __clk_get_name(pll->clkr.hw.clk);

	/* Wait for pll to enable. */
	for (count = 200; count > 0; count--) {
		ret = regmap_read(pll->clkr.regmap, pll->status_reg, &val);
		if (ret)
			return ret;
		if (val & BIT(pll->status_bit))
			return 0;
		udelay(1);
	}

	WARN(1, "%s didn't enable after voting for it!\n", name);
	return -ETIMEDOUT;
}

static int clk_pll_vote_enable(struct clk_hw *hw)
{
	int ret;
	struct clk_pll *p = to_clk_pll(__clk_get_hw(__clk_get_parent(hw->clk)));

	ret = clk_enable_regmap(hw);
	if (ret)
		return ret;

	return wait_for_pll(p);
}

const struct clk_ops clk_pll_vote_ops = {
	.enable = clk_pll_vote_enable,
	.disable = clk_disable_regmap,
};
EXPORT_SYMBOL_GPL(clk_pll_vote_ops);

static void
clk_pll_set_fsm_mode(struct clk_pll *pll, struct regmap *regmap, u8 lock_count)
{
	u32 val;
	u32 mask;

	/* De-assert reset to FSM */
	regmap_update_bits(regmap, pll->mode_reg, PLL_VOTE_FSM_RESET, 0);

	/* Program bias count and lock count */
	val = 1 << PLL_BIAS_COUNT_SHIFT | lock_count << PLL_LOCK_COUNT_SHIFT;
	mask = PLL_BIAS_COUNT_MASK << PLL_BIAS_COUNT_SHIFT;
	mask |= PLL_LOCK_COUNT_MASK << PLL_LOCK_COUNT_SHIFT;
	regmap_update_bits(regmap, pll->mode_reg, mask, val);

	/* Enable PLL FSM voting */
	regmap_update_bits(regmap, pll->mode_reg, PLL_VOTE_FSM_ENA,
		PLL_VOTE_FSM_ENA);
}

static void clk_pll_configure(struct clk_pll *pll, struct regmap *regmap,
	const struct pll_config *config)
{
	u32 val;
	u32 mask;

	regmap_write(regmap, pll->l_reg, config->l);
	regmap_write(regmap, pll->m_reg, config->m);
	regmap_write(regmap, pll->n_reg, config->n);

	val = config->vco_val;
	val |= config->pre_div_val;
	val |= config->post_div_val;
	val |= config->mn_ena_mask;
	val |= config->main_output_mask;
	val |= config->aux_output_mask;

	mask = config->vco_mask;
	mask |= config->pre_div_mask;
	mask |= config->post_div_mask;
	mask |= config->mn_ena_mask;
	mask |= config->main_output_mask;
	mask |= config->aux_output_mask;

	regmap_update_bits(regmap, pll->config_reg, mask, val);
}

void clk_pll_configure_sr(struct clk_pll *pll, struct regmap *regmap,
		const struct pll_config *config, bool fsm_mode)
{
	clk_pll_configure(pll, regmap, config);
	if (fsm_mode)
		clk_pll_set_fsm_mode(pll, regmap, 8);
}
EXPORT_SYMBOL_GPL(clk_pll_configure_sr);

void clk_pll_configure_sr_hpm_lp(struct clk_pll *pll, struct regmap *regmap,
		const struct pll_config *config, bool fsm_mode)
{
	clk_pll_configure(pll, regmap, config);
	if (fsm_mode)
		clk_pll_set_fsm_mode(pll, regmap, 0);
}
EXPORT_SYMBOL_GPL(clk_pll_configure_sr_hpm_lp);
Commit	Line	Data
9e263131 SB	1	/*
	2	* Copyright (c) 2013, The Linux Foundation. All rights reserved.
	3	*
	4	* This software is licensed under the terms of the GNU General Public
	5	* License version 2, as published by the Free Software Foundation, and
	6	* may be copied, distributed, and modified under those terms.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*/
	13
	14	#include <linux/kernel.h>
	15	#include <linux/bitops.h>
	16	#include <linux/err.h>
	17	#include <linux/bug.h>
	18	#include <linux/delay.h>
	19	#include <linux/export.h>
	20	#include <linux/clk-provider.h>
	21	#include <linux/regmap.h>
	22
	23	#include <asm/div64.h>
	24
	25	#include "clk-pll.h"
	26
	27	#define PLL_OUTCTRL BIT(0)
	28	#define PLL_BYPASSNL BIT(1)
	29	#define PLL_RESET_N BIT(2)
	30	#define PLL_LOCK_COUNT_SHIFT 8
	31	#define PLL_LOCK_COUNT_MASK 0x3f
	32	#define PLL_BIAS_COUNT_SHIFT 14
	33	#define PLL_BIAS_COUNT_MASK 0x3f
	34	#define PLL_VOTE_FSM_ENA BIT(20)
	35	#define PLL_VOTE_FSM_RESET BIT(21)
	36
	37	static int clk_pll_enable(struct clk_hw *hw)
	38	{
	39	struct clk_pll *pll = to_clk_pll(hw);
	40	int ret;
	41	u32 mask, val;
	42
	43	mask = PLL_OUTCTRL \| PLL_RESET_N \| PLL_BYPASSNL;
	44	ret = regmap_read(pll->clkr.regmap, pll->mode_reg, &val);
	45	if (ret)
	46	return ret;
	47
	48	/* Skip if already enabled or in FSM mode */
	49	if ((val & mask) == mask \|\| val & PLL_VOTE_FSM_ENA)
	50	return 0;
	51
	52	/* Disable PLL bypass mode. */
	53	ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_BYPASSNL,
	54	PLL_BYPASSNL);
	55	if (ret)
	56	return ret;
	57
	58	/*
	59	* H/W requires a 5us delay between disabling the bypass and
	60	* de-asserting the reset. Delay 10us just to be safe.
	61	*/
	62	udelay(10);
	63
	64	/* De-assert active-low PLL reset. */
65	ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_RESET_N,
66	PLL_RESET_N);
67	if (ret)
68	return ret;
69
70	/* Wait until PLL is locked. */
71	udelay(50);
72
73	/* Enable PLL output. */
d41bd923	74	return regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_OUTCTRL,
9e263131	75	PLL_OUTCTRL);
9e263131 SB	76	}
	77
	78	static void clk_pll_disable(struct clk_hw *hw)
	79	{
	80	struct clk_pll *pll = to_clk_pll(hw);
	81	u32 mask;
	82	u32 val;
	83
	84	regmap_read(pll->clkr.regmap, pll->mode_reg, &val);
	85	/* Skip if in FSM mode */
	86	if (val & PLL_VOTE_FSM_ENA)
	87	return;
	88	mask = PLL_OUTCTRL \| PLL_RESET_N \| PLL_BYPASSNL;
	89	regmap_update_bits(pll->clkr.regmap, pll->mode_reg, mask, 0);
	90	}
	91
	92	static unsigned long
	93	clk_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
	94	{
	95	struct clk_pll *pll = to_clk_pll(hw);
ae3669ac	96	u32 l, m, n, config;
9e263131 SB	97	unsigned long rate;
	98	u64 tmp;
	99
	100	regmap_read(pll->clkr.regmap, pll->l_reg, &l);
	101	regmap_read(pll->clkr.regmap, pll->m_reg, &m);
	102	regmap_read(pll->clkr.regmap, pll->n_reg, &n);
	103
	104	l &= 0x3ff;
	105	m &= 0x7ffff;
	106	n &= 0x7ffff;
	107
	108	rate = parent_rate * l;
	109	if (n) {
	110	tmp = parent_rate;
	111	tmp *= m;
	112	do_div(tmp, n);
	113	rate += tmp;
	114	}
ae3669ac SB	115	if (pll->post_div_width) {
	116	regmap_read(pll->clkr.regmap, pll->config_reg, &config);
	117	config >>= pll->post_div_shift;
	118	config &= BIT(pll->post_div_width) - 1;
	119	rate /= config + 1;
	120	}
	121
9e263131 SB	122	return rate;
	123	}
	124
ae3669ac SB	125	static const
	126	struct pll_freq_tbl find_freq(const struct pll_freq_tbl f, unsigned long rate)
	127	{
	128	if (!f)
	129	return NULL;
	130
	131	for (; f->freq; f++)
	132	if (rate <= f->freq)
	133	return f;
	134
	135	return NULL;
	136	}
	137
0817b62c BB	138	static int
0817b62c BB	139	clk_pll_determine_rate(struct clk_hw hw, struct clk_rate_request req)
ae3669ac	140	{
0817b62c	141	struct clk *parent = __clk_get_parent(hw->clk);
ae3669ac SB	142	struct clk_pll *pll = to_clk_pll(hw);
	143	const struct pll_freq_tbl *f;
	144
0817b62c BB	145	req->best_parent_hw = __clk_get_hw(parent);
	146	req->best_parent_rate = __clk_get_rate(parent);
	147
	148	f = find_freq(pll->freq_tbl, req->rate);
ae3669ac	149	if (!f)
0817b62c BB	150	req->rate = clk_pll_recalc_rate(hw, req->best_parent_rate);
	151	else
	152	req->rate = f->freq;
ae3669ac	153
0817b62c	154	return 0;
ae3669ac SB	155	}
	156
	157	static int
	158	clk_pll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long p_rate)
	159	{
	160	struct clk_pll *pll = to_clk_pll(hw);
	161	const struct pll_freq_tbl *f;
	162	bool enabled;
	163	u32 mode;
	164	u32 enable_mask = PLL_OUTCTRL \| PLL_BYPASSNL \| PLL_RESET_N;
	165
	166	f = find_freq(pll->freq_tbl, rate);
	167	if (!f)
	168	return -EINVAL;
	169
	170	regmap_read(pll->clkr.regmap, pll->mode_reg, &mode);
	171	enabled = (mode & enable_mask) == enable_mask;
	172
	173	if (enabled)
	174	clk_pll_disable(hw);
	175
	176	regmap_update_bits(pll->clkr.regmap, pll->l_reg, 0x3ff, f->l);
	177	regmap_update_bits(pll->clkr.regmap, pll->m_reg, 0x7ffff, f->m);
	178	regmap_update_bits(pll->clkr.regmap, pll->n_reg, 0x7ffff, f->n);
	179	regmap_write(pll->clkr.regmap, pll->config_reg, f->ibits);
	180
	181	if (enabled)
	182	clk_pll_enable(hw);
	183
	184	return 0;
	185	}
	186
9e263131 SB	187	const struct clk_ops clk_pll_ops = {
	188	.enable = clk_pll_enable,
	189	.disable = clk_pll_disable,
	190	.recalc_rate = clk_pll_recalc_rate,
ae3669ac SB	191	.determine_rate = clk_pll_determine_rate,
ae3669ac SB	192	.set_rate = clk_pll_set_rate,
9e263131 SB	193	};
	194	EXPORT_SYMBOL_GPL(clk_pll_ops);
	195
	196	static int wait_for_pll(struct clk_pll *pll)
	197	{
	198	u32 val;
	199	int count;
	200	int ret;
	201	const char *name = __clk_get_name(pll->clkr.hw.clk);
	202
	203	/* Wait for pll to enable. */
	204	for (count = 200; count > 0; count--) {
	205	ret = regmap_read(pll->clkr.regmap, pll->status_reg, &val);
	206	if (ret)
	207	return ret;
	208	if (val & BIT(pll->status_bit))
	209	return 0;
	210	udelay(1);
	211	}
	212
	213	WARN(1, "%s didn't enable after voting for it!\n", name);
	214	return -ETIMEDOUT;
	215	}
	216
	217	static int clk_pll_vote_enable(struct clk_hw *hw)
	218	{
	219	int ret;
	220	struct clk_pll *p = to_clk_pll(__clk_get_hw(__clk_get_parent(hw->clk)));
	221
	222	ret = clk_enable_regmap(hw);
	223	if (ret)
	224	return ret;
	225
	226	return wait_for_pll(p);
	227	}
	228
	229	const struct clk_ops clk_pll_vote_ops = {
	230	.enable = clk_pll_vote_enable,
	231	.disable = clk_disable_regmap,
	232	};
	233	EXPORT_SYMBOL_GPL(clk_pll_vote_ops);
	234
	235	static void
d8c25d3a	236	clk_pll_set_fsm_mode(struct clk_pll pll, struct regmap regmap, u8 lock_count)
9e263131 SB	237	{
	238	u32 val;
	239	u32 mask;
	240
	241	/* De-assert reset to FSM */
	242	regmap_update_bits(regmap, pll->mode_reg, PLL_VOTE_FSM_RESET, 0);
	243
	244	/* Program bias count and lock count */
d8c25d3a	245	val = 1 << PLL_BIAS_COUNT_SHIFT \| lock_count << PLL_LOCK_COUNT_SHIFT;
9e263131 SB	246	mask = PLL_BIAS_COUNT_MASK << PLL_BIAS_COUNT_SHIFT;
	247	mask \|= PLL_LOCK_COUNT_MASK << PLL_LOCK_COUNT_SHIFT;
	248	regmap_update_bits(regmap, pll->mode_reg, mask, val);
	249
	250	/* Enable PLL FSM voting */
	251	regmap_update_bits(regmap, pll->mode_reg, PLL_VOTE_FSM_ENA,
	252	PLL_VOTE_FSM_ENA);
	253	}
	254
	255	static void clk_pll_configure(struct clk_pll pll, struct regmap regmap,
	256	const struct pll_config *config)
	257	{
	258	u32 val;
	259	u32 mask;
	260
	261	regmap_write(regmap, pll->l_reg, config->l);
	262	regmap_write(regmap, pll->m_reg, config->m);
	263	regmap_write(regmap, pll->n_reg, config->n);
	264
	265	val = config->vco_val;
	266	val \|= config->pre_div_val;
	267	val \|= config->post_div_val;
	268	val \|= config->mn_ena_mask;
	269	val \|= config->main_output_mask;
	270	val \|= config->aux_output_mask;
	271
	272	mask = config->vco_mask;
	273	mask \|= config->pre_div_mask;
	274	mask \|= config->post_div_mask;
	275	mask \|= config->mn_ena_mask;
	276	mask \|= config->main_output_mask;
	277	mask \|= config->aux_output_mask;
	278
	279	regmap_update_bits(regmap, pll->config_reg, mask, val);
	280	}
	281
d8c25d3a SB	282	void clk_pll_configure_sr(struct clk_pll pll, struct regmap regmap,
	283	const struct pll_config *config, bool fsm_mode)
	284	{
	285	clk_pll_configure(pll, regmap, config);
	286	if (fsm_mode)
	287	clk_pll_set_fsm_mode(pll, regmap, 8);
	288	}
	289	EXPORT_SYMBOL_GPL(clk_pll_configure_sr);
	290
9e263131 SB	291	void clk_pll_configure_sr_hpm_lp(struct clk_pll pll, struct regmap regmap,
	292	const struct pll_config *config, bool fsm_mode)
	293	{
	294	clk_pll_configure(pll, regmap, config);
	295	if (fsm_mode)
d8c25d3a	296	clk_pll_set_fsm_mode(pll, regmap, 0);
9e263131 SB	297	}
9e263131 SB	298	EXPORT_SYMBOL_GPL(clk_pll_configure_sr_hpm_lp);