Commit bcd61c0f authored by Stephen Boyd's avatar Stephen Boyd Committed by Mike Turquette
Browse files

clk: qcom: Add support for root clock generators (RCGs) 



Add support for the root clock generators on Qualcomm devices.
RCGs are highly customizable mux/divider/counter clocks that can
be used to generate almost any rate desired given some input
source that is faster than the desired rate.

Signed-off-by: default avatarStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: default avatarMike Turquette <mturquette@linaro.org>
parent 9e263131

drivers/clk/qcom/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -2,3 +2,5 @@ obj-$(CONFIG_COMMON_CLK_QCOM) += clk-qcom.o 


clk-qcom-$(CONFIG_COMMON_CLK_QCOM) += clk-regmap.o

clk-qcom-$(CONFIG_COMMON_CLK_QCOM) += clk-pll.o

clk-qcom-$(CONFIG_COMMON_CLK_QCOM) += clk-rcg.o

clk-qcom-$(CONFIG_COMMON_CLK_QCOM) += clk-rcg2.o

drivers/clk/qcom/clk-rcg.c

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/*

 * 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/export.h>

#include <linux/clk-provider.h>

#include <linux/regmap.h>



#include <asm/div64.h>



#include "clk-rcg.h"



static u32 ns_to_src(struct src_sel *s, u32 ns)

{

	ns >>= s->src_sel_shift;

	ns &= SRC_SEL_MASK;

	return ns;

}



static u32 src_to_ns(struct src_sel *s, u8 src, u32 ns)

{

	u32 mask;



	mask = SRC_SEL_MASK;

	mask <<= s->src_sel_shift;

	ns &= ~mask;



	ns |= src << s->src_sel_shift;

	return ns;

}



static u8 clk_rcg_get_parent(struct clk_hw *hw)

{

	struct clk_rcg *rcg = to_clk_rcg(hw);

	int num_parents = __clk_get_num_parents(hw->clk);

	u32 ns;

	int i;



	regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);

	ns = ns_to_src(&rcg->s, ns);

	for (i = 0; i < num_parents; i++)

		if (ns == rcg->s.parent_map[i])

			return i;



	return -EINVAL;

}



static int reg_to_bank(struct clk_dyn_rcg *rcg, u32 bank)

{

	bank &= BIT(rcg->mux_sel_bit);

	return !!bank;

}



static u8 clk_dyn_rcg_get_parent(struct clk_hw *hw)

{

	struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);

	int num_parents = __clk_get_num_parents(hw->clk);

	u32 ns, ctl;

	int bank;

	int i;

	struct src_sel *s;



	regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &ctl);

	bank = reg_to_bank(rcg, ctl);

	s = &rcg->s[bank];



	regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);

	ns = ns_to_src(s, ns);



	for (i = 0; i < num_parents; i++)

		if (ns == s->parent_map[i])

			return i;



	return -EINVAL;

}



static int clk_rcg_set_parent(struct clk_hw *hw, u8 index)

{

	struct clk_rcg *rcg = to_clk_rcg(hw);

	u32 ns;



	regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);

	ns = src_to_ns(&rcg->s, rcg->s.parent_map[index], ns);

	regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns);



	return 0;

}



static u32 md_to_m(struct mn *mn, u32 md)

{

	md >>= mn->m_val_shift;

	md &= BIT(mn->width) - 1;

	return md;

}



static u32 ns_to_pre_div(struct pre_div *p, u32 ns)

{

	ns >>= p->pre_div_shift;

	ns &= BIT(p->pre_div_width) - 1;

	return ns;

}



static u32 pre_div_to_ns(struct pre_div *p, u8 pre_div, u32 ns)

{

	u32 mask;



	mask = BIT(p->pre_div_width) - 1;

	mask <<= p->pre_div_shift;

	ns &= ~mask;



	ns |= pre_div << p->pre_div_shift;

	return ns;

}



static u32 mn_to_md(struct mn *mn, u32 m, u32 n, u32 md)

{

	u32 mask, mask_w;



	mask_w = BIT(mn->width) - 1;

	mask = (mask_w << mn->m_val_shift) | mask_w;

	md &= ~mask;



	if (n) {

		m <<= mn->m_val_shift;

		md |= m;

		md |= ~n & mask_w;

	}



	return md;

}



static u32 ns_m_to_n(struct mn *mn, u32 ns, u32 m)

{

	ns = ~ns >> mn->n_val_shift;

	ns &= BIT(mn->width) - 1;

	return ns + m;

}



static u32 reg_to_mnctr_mode(struct mn *mn, u32 val)

{

	val >>= mn->mnctr_mode_shift;

	val &= MNCTR_MODE_MASK;

	return val;

}



static u32 mn_to_ns(struct mn *mn, u32 m, u32 n, u32 ns)

{

	u32 mask;



	mask = BIT(mn->width) - 1;

	mask <<= mn->n_val_shift;

	ns &= ~mask;



	if (n) {

		n = n - m;

		n = ~n;

		n &= BIT(mn->width) - 1;

		n <<= mn->n_val_shift;

		ns |= n;

	}



	return ns;

}



static u32 mn_to_reg(struct mn *mn, u32 m, u32 n, u32 val)

{

	u32 mask;



	mask = MNCTR_MODE_MASK << mn->mnctr_mode_shift;

	mask |= BIT(mn->mnctr_en_bit);

	val &= ~mask;



	if (n) {

		val |= BIT(mn->mnctr_en_bit);

		val |= MNCTR_MODE_DUAL << mn->mnctr_mode_shift;

	}



	return val;

}



static void configure_bank(struct clk_dyn_rcg *rcg, const struct freq_tbl *f)

{

	u32 ns, md, ctl, *regp;

	int bank, new_bank;

	struct mn *mn;

	struct pre_div *p;

	struct src_sel *s;

	bool enabled;

	u32 md_reg;

	u32 bank_reg;

	bool banked_mn = !!rcg->mn[1].width;

	struct clk_hw *hw = &rcg->clkr.hw;



	enabled = __clk_is_enabled(hw->clk);



	regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);

	regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &ctl);



	if (banked_mn) {

		regp = &ctl;

		bank_reg = rcg->clkr.enable_reg;

	} else {

		regp = &ns;

		bank_reg = rcg->ns_reg;

	}



	bank = reg_to_bank(rcg, *regp);

	new_bank = enabled ? !bank : bank;



	if (banked_mn) {

		mn = &rcg->mn[new_bank];

		md_reg = rcg->md_reg[new_bank];



		ns |= BIT(mn->mnctr_reset_bit);

		regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns);



		regmap_read(rcg->clkr.regmap, md_reg, &md);

		md = mn_to_md(mn, f->m, f->n, md);

		regmap_write(rcg->clkr.regmap, md_reg, md);



		ns = mn_to_ns(mn, f->m, f->n, ns);

		regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns);



		ctl = mn_to_reg(mn, f->m, f->n, ctl);

		regmap_write(rcg->clkr.regmap, rcg->clkr.enable_reg, ctl);



		ns &= ~BIT(mn->mnctr_reset_bit);

		regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns);

	} else {

		p = &rcg->p[new_bank];

		ns = pre_div_to_ns(p, f->pre_div - 1, ns);

	}



	s = &rcg->s[new_bank];

	ns = src_to_ns(s, s->parent_map[f->src], ns);

	regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns);



	if (enabled) {

		*regp ^= BIT(rcg->mux_sel_bit);

		regmap_write(rcg->clkr.regmap, bank_reg, *regp);

	}

}



static int clk_dyn_rcg_set_parent(struct clk_hw *hw, u8 index)

{

	struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);

	u32 ns, ctl, md, reg;

	int bank;

	struct freq_tbl f = { 0 };

	bool banked_mn = !!rcg->mn[1].width;



	regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);

	regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &ctl);

	reg = banked_mn ? ctl : ns;



	bank = reg_to_bank(rcg, reg);



	if (banked_mn) {

		regmap_read(rcg->clkr.regmap, rcg->md_reg[bank], &md);

		f.m = md_to_m(&rcg->mn[bank], md);

		f.n = ns_m_to_n(&rcg->mn[bank], ns, f.m);

	} else {

		f.pre_div = ns_to_pre_div(&rcg->p[bank], ns) + 1;

	}

	f.src = index;



	configure_bank(rcg, &f);



	return 0;

}



/*

 * Calculate m/n:d rate

 *

 *          parent_rate     m

 *   rate = ----------- x  ---

 *            pre_div       n

 */

static unsigned long

calc_rate(unsigned long rate, u32 m, u32 n, u32 mode, u32 pre_div)

{

	if (pre_div)

		rate /= pre_div + 1;



	if (mode) {

		u64 tmp = rate;

		tmp *= m;

		do_div(tmp, n);

		rate = tmp;

	}



	return rate;

}



static unsigned long

clk_rcg_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)

{

	struct clk_rcg *rcg = to_clk_rcg(hw);

	u32 pre_div, m = 0, n = 0, ns, md, mode = 0;

	struct mn *mn = &rcg->mn;



	regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);

	pre_div = ns_to_pre_div(&rcg->p, ns);



	if (rcg->mn.width) {

		regmap_read(rcg->clkr.regmap, rcg->md_reg, &md);

		m = md_to_m(mn, md);

		n = ns_m_to_n(mn, ns, m);

		/* MN counter mode is in hw.enable_reg sometimes */

		if (rcg->clkr.enable_reg != rcg->ns_reg)

			regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &mode);

		else

			mode = ns;

		mode = reg_to_mnctr_mode(mn, mode);

	}



	return calc_rate(parent_rate, m, n, mode, pre_div);

}



static unsigned long

clk_dyn_rcg_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)

{

	struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);

	u32 m, n, pre_div, ns, md, mode, reg;

	int bank;

	struct mn *mn;

	bool banked_mn = !!rcg->mn[1].width;



	regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);



	if (banked_mn)

		regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &reg);

	else

		reg = ns;



	bank = reg_to_bank(rcg, reg);



	if (banked_mn) {

		mn = &rcg->mn[bank];

		regmap_read(rcg->clkr.regmap, rcg->md_reg[bank], &md);

		m = md_to_m(mn, md);

		n = ns_m_to_n(mn, ns, m);

		mode = reg_to_mnctr_mode(mn, reg);

		return calc_rate(parent_rate, m, n, mode, 0);

	} else {

		pre_div = ns_to_pre_div(&rcg->p[bank], ns);

		return calc_rate(parent_rate, 0, 0, 0, pre_div);

	}

}



static const

struct freq_tbl *find_freq(const struct freq_tbl *f, unsigned long rate)

{

	if (!f)

		return NULL;



	for (; f->freq; f++)

		if (rate <= f->freq)

			return f;



	return NULL;

}



static long _freq_tbl_determine_rate(struct clk_hw *hw,

		const struct freq_tbl *f, unsigned long rate,

		unsigned long *p_rate, struct clk **p)

{

	unsigned long clk_flags;



	f = find_freq(f, rate);

	if (!f)

		return -EINVAL;



	clk_flags = __clk_get_flags(hw->clk);

	*p = clk_get_parent_by_index(hw->clk, f->src);

	if (clk_flags & CLK_SET_RATE_PARENT) {

		rate = rate * f->pre_div;

		if (f->n) {

			u64 tmp = rate;

			tmp = tmp * f->n;

			do_div(tmp, f->m);

			rate = tmp;

		}

	} else {

		rate =  __clk_get_rate(*p);

	}

	*p_rate = rate;



	return f->freq;

}



static long clk_rcg_determine_rate(struct clk_hw *hw, unsigned long rate,

		unsigned long *p_rate, struct clk **p)

{

	struct clk_rcg *rcg = to_clk_rcg(hw);



	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p);

}



static long clk_dyn_rcg_determine_rate(struct clk_hw *hw, unsigned long rate,

		unsigned long *p_rate, struct clk **p)

{

	struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);



	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p);

}



static int clk_rcg_set_rate(struct clk_hw *hw, unsigned long rate,

			    unsigned long parent_rate)

{

	struct clk_rcg *rcg = to_clk_rcg(hw);

	const struct freq_tbl *f;

	u32 ns, md, ctl;

	struct mn *mn = &rcg->mn;

	u32 mask = 0;

	unsigned int reset_reg;



	f = find_freq(rcg->freq_tbl, rate);

	if (!f)

		return -EINVAL;



	if (rcg->mn.reset_in_cc)

		reset_reg = rcg->clkr.enable_reg;

	else

		reset_reg = rcg->ns_reg;



	if (rcg->mn.width) {

		mask = BIT(mn->mnctr_reset_bit);

		regmap_update_bits(rcg->clkr.regmap, reset_reg, mask, mask);



		regmap_read(rcg->clkr.regmap, rcg->md_reg, &md);

		md = mn_to_md(mn, f->m, f->n, md);

		regmap_write(rcg->clkr.regmap, rcg->md_reg, md);



		regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);

		/* MN counter mode is in hw.enable_reg sometimes */

		if (rcg->clkr.enable_reg != rcg->ns_reg) {

			regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &ctl);

			ctl = mn_to_reg(mn, f->m, f->n, ctl);

			regmap_write(rcg->clkr.regmap, rcg->clkr.enable_reg, ctl);

		} else {

			ns = mn_to_reg(mn, f->m, f->n, ns);

		}

		ns = mn_to_ns(mn, f->m, f->n, ns);

	} else {

		regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns);

	}



	ns = pre_div_to_ns(&rcg->p, f->pre_div - 1, ns);

	regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns);



	regmap_update_bits(rcg->clkr.regmap, reset_reg, mask, 0);



	return 0;

}



static int __clk_dyn_rcg_set_rate(struct clk_hw *hw, unsigned long rate)

{

	struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw);

	const struct freq_tbl *f;



	f = find_freq(rcg->freq_tbl, rate);

	if (!f)

		return -EINVAL;



	configure_bank(rcg, f);



	return 0;

}



static int clk_dyn_rcg_set_rate(struct clk_hw *hw, unsigned long rate,

			    unsigned long parent_rate)

{

	return __clk_dyn_rcg_set_rate(hw, rate);

}



static int clk_dyn_rcg_set_rate_and_parent(struct clk_hw *hw,

		unsigned long rate, unsigned long parent_rate, u8 index)

{

	return __clk_dyn_rcg_set_rate(hw, rate);

}



const struct clk_ops clk_rcg_ops = {

	.enable = clk_enable_regmap,

	.disable = clk_disable_regmap,

	.get_parent = clk_rcg_get_parent,

	.set_parent = clk_rcg_set_parent,

	.recalc_rate = clk_rcg_recalc_rate,

	.determine_rate = clk_rcg_determine_rate,

	.set_rate = clk_rcg_set_rate,

};

EXPORT_SYMBOL_GPL(clk_rcg_ops);



const struct clk_ops clk_dyn_rcg_ops = {

	.enable = clk_enable_regmap,

	.is_enabled = clk_is_enabled_regmap,

	.disable = clk_disable_regmap,

	.get_parent = clk_dyn_rcg_get_parent,

	.set_parent = clk_dyn_rcg_set_parent,

	.recalc_rate = clk_dyn_rcg_recalc_rate,

	.determine_rate = clk_dyn_rcg_determine_rate,

	.set_rate = clk_dyn_rcg_set_rate,

	.set_rate_and_parent = clk_dyn_rcg_set_rate_and_parent,

};

EXPORT_SYMBOL_GPL(clk_dyn_rcg_ops);

drivers/clk/qcom/clk-rcg.h

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/*

 * 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.

 */



#ifndef __QCOM_CLK_RCG_H__

#define __QCOM_CLK_RCG_H__



#include <linux/clk-provider.h>

#include "clk-regmap.h"



struct freq_tbl {

	unsigned long freq;

	u8 src;

	u8 pre_div;

	u16 m;

	u16 n;

};



/**

 * struct mn - M/N:D counter

 * @mnctr_en_bit: bit to enable mn counter

 * @mnctr_reset_bit: bit to assert mn counter reset

 * @mnctr_mode_shift: lowest bit of mn counter mode field

 * @n_val_shift: lowest bit of n value field

 * @m_val_shift: lowest bit of m value field

 * @width: number of bits in m/n/d values

 * @reset_in_cc: true if the mnctr_reset_bit is in the CC register

 */

struct mn {

	u8		mnctr_en_bit;

	u8		mnctr_reset_bit;

	u8		mnctr_mode_shift;

#define MNCTR_MODE_DUAL 0x2

#define MNCTR_MODE_MASK 0x3

	u8		n_val_shift;

	u8		m_val_shift;

	u8		width;

	bool		reset_in_cc;

};



/**

 * struct pre_div - pre-divider

 * @pre_div_shift: lowest bit of pre divider field

 * @pre_div_width: number of bits in predivider

 */

struct pre_div {

	u8		pre_div_shift;

	u8		pre_div_width;

};



/**

 * struct src_sel - source selector

 * @src_sel_shift: lowest bit of source selection field

 * @parent_map: map from software's parent index to hardware's src_sel field

 */

struct src_sel {

	u8		src_sel_shift;

#define SRC_SEL_MASK	0x7

	const u8	*parent_map;

};



/**

 * struct clk_rcg - root clock generator

 *

 * @ns_reg: NS register

 * @md_reg: MD register

 * @mn: mn counter

 * @p: pre divider

 * @s: source selector

 * @freq_tbl: frequency table

 * @clkr: regmap clock handle

 * @lock: register lock

 *

 */

struct clk_rcg {

	u32		ns_reg;

	u32		md_reg;



	struct mn	mn;

	struct pre_div	p;

	struct src_sel	s;



	const struct freq_tbl	*freq_tbl;



	struct clk_regmap	clkr;

};



extern const struct clk_ops clk_rcg_ops;



#define to_clk_rcg(_hw) container_of(to_clk_regmap(_hw), struct clk_rcg, clkr)



/**

 * struct clk_dyn_rcg - root clock generator with glitch free mux

 *

 * @mux_sel_bit: bit to switch glitch free mux

 * @ns_reg: NS register

 * @md_reg: MD0 and MD1 register

 * @mn: mn counter (banked)

 * @s: source selector (banked)

 * @freq_tbl: frequency table

 * @clkr: regmap clock handle

 * @lock: register lock

 *

 */

struct clk_dyn_rcg {

	u32	ns_reg;

	u32	md_reg[2];



	u8	mux_sel_bit;



	struct mn	mn[2];

	struct pre_div	p[2];

	struct src_sel	s[2];



	const struct freq_tbl *freq_tbl;



	struct clk_regmap clkr;

};



extern const struct clk_ops clk_dyn_rcg_ops;



#define to_clk_dyn_rcg(_hw) \

	container_of(to_clk_regmap(_hw), struct clk_dyn_rcg, clkr)



/**

 * struct clk_rcg2 - root clock generator

 *

 * @cmd_rcgr: corresponds to *_CMD_RCGR

 * @mnd_width: number of bits in m/n/d values

 * @hid_width: number of bits in half integer divider

 * @parent_map: map from software's parent index to hardware's src_sel field

 * @freq_tbl: frequency table

 * @clkr: regmap clock handle

 * @lock: register lock

 *

 */

struct clk_rcg2 {

	u32			cmd_rcgr;

	u8			mnd_width;

	u8			hid_width;

	const u8		*parent_map;

	const struct freq_tbl	*freq_tbl;

	struct clk_regmap	clkr;

};



#define to_clk_rcg2(_hw) container_of(to_clk_regmap(_hw), struct clk_rcg2, clkr)



extern const struct clk_ops clk_rcg2_ops;



#endif

drivers/clk/qcom/clk-rcg2.c

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Original line number Diff line number Diff line 
/*

 * 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/export.h>

#include <linux/clk-provider.h>

#include <linux/delay.h>

#include <linux/regmap.h>



#include <asm/div64.h>



#include "clk-rcg.h"



#define CMD_REG			0x0

#define CMD_UPDATE		BIT(0)

#define CMD_ROOT_EN		BIT(1)

#define CMD_DIRTY_CFG		BIT(4)

#define CMD_DIRTY_N		BIT(5)

#define CMD_DIRTY_M		BIT(6)

#define CMD_DIRTY_D		BIT(7)

#define CMD_ROOT_OFF		BIT(31)



#define CFG_REG			0x4

#define CFG_SRC_DIV_SHIFT	0

#define CFG_SRC_SEL_SHIFT	8

#define CFG_SRC_SEL_MASK	(0x7 << CFG_SRC_SEL_SHIFT)

#define CFG_MODE_SHIFT		12

#define CFG_MODE_MASK		(0x3 << CFG_MODE_SHIFT)

#define CFG_MODE_DUAL_EDGE	(0x2 << CFG_MODE_SHIFT)



#define M_REG			0x8

#define N_REG			0xc

#define D_REG			0x10



static int clk_rcg2_is_enabled(struct clk_hw *hw)

{

	struct clk_rcg2 *rcg = to_clk_rcg2(hw);

	u32 cmd;

	int ret;



	ret = regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CMD_REG, &cmd);

	if (ret)

		return ret;



	return (cmd & CMD_ROOT_OFF) != 0;

}



static u8 clk_rcg2_get_parent(struct clk_hw *hw)

{

	struct clk_rcg2 *rcg = to_clk_rcg2(hw);

	int num_parents = __clk_get_num_parents(hw->clk);

	u32 cfg;

	int i, ret;



	ret = regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG, &cfg);

	if (ret)

		return ret;



	cfg &= CFG_SRC_SEL_MASK;

	cfg >>= CFG_SRC_SEL_SHIFT;



	for (i = 0; i < num_parents; i++)

		if (cfg == rcg->parent_map[i])

			return i;



	return -EINVAL;

}



static int update_config(struct clk_rcg2 *rcg)

{

	int count, ret;

	u32 cmd;

	struct clk_hw *hw = &rcg->clkr.hw;

	const char *name = __clk_get_name(hw->clk);



	ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + CMD_REG,

				 CMD_UPDATE, CMD_UPDATE);

	if (ret)

		return ret;



	/* Wait for update to take effect */

	for (count = 500; count > 0; count--) {

		ret = regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CMD_REG, &cmd);

		if (ret)

			return ret;

		if (!(cmd & CMD_UPDATE))

			return 0;

		udelay(1);

	}



	WARN(1, "%s: rcg didn't update its configuration.", name);

	return 0;

}



static int clk_rcg2_set_parent(struct clk_hw *hw, u8 index)

{

	struct clk_rcg2 *rcg = to_clk_rcg2(hw);

	int ret;



	ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG,

				 CFG_SRC_SEL_MASK,

				 rcg->parent_map[index] << CFG_SRC_SEL_SHIFT);

	if (ret)

		return ret;



	return update_config(rcg);

}



/*

 * Calculate m/n:d rate

 *

 *          parent_rate     m

 *   rate = ----------- x  ---

 *            hid_div       n

 */

static unsigned long

calc_rate(unsigned long rate, u32 m, u32 n, u32 mode, u32 hid_div)

{

	if (hid_div) {

		rate *= 2;

		rate /= hid_div + 1;

	}



	if (mode) {

		u64 tmp = rate;

		tmp *= m;

		do_div(tmp, n);

		rate = tmp;

	}



	return rate;

}



static unsigned long

clk_rcg2_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)

{

	struct clk_rcg2 *rcg = to_clk_rcg2(hw);

	u32 cfg, hid_div, m = 0, n = 0, mode = 0, mask;



	regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG, &cfg);



	if (rcg->mnd_width) {

		mask = BIT(rcg->mnd_width) - 1;

		regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + M_REG, &m);

		m &= mask;

		regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + N_REG, &n);

		n =  ~n;

		n &= mask;

		n += m;

		mode = cfg & CFG_MODE_MASK;

		mode >>= CFG_MODE_SHIFT;

	}



	mask = BIT(rcg->hid_width) - 1;

	hid_div = cfg >> CFG_SRC_DIV_SHIFT;

	hid_div &= mask;



	return calc_rate(parent_rate, m, n, mode, hid_div);

}



static const

struct freq_tbl *find_freq(const struct freq_tbl *f, unsigned long rate)

{

	if (!f)

		return NULL;



	for (; f->freq; f++)

		if (rate <= f->freq)

			return f;



	return NULL;

}



static long _freq_tbl_determine_rate(struct clk_hw *hw,

		const struct freq_tbl *f, unsigned long rate,

		unsigned long *p_rate, struct clk **p)

{

	unsigned long clk_flags;



	f = find_freq(f, rate);

	if (!f)

		return -EINVAL;



	clk_flags = __clk_get_flags(hw->clk);

	*p = clk_get_parent_by_index(hw->clk, f->src);

	if (clk_flags & CLK_SET_RATE_PARENT) {

		if (f->pre_div) {

			rate /= 2;

			rate *= f->pre_div + 1;

		}



		if (f->n) {

			u64 tmp = rate;

			tmp = tmp * f->n;

			do_div(tmp, f->m);

			rate = tmp;

		}

	} else {

		rate =  __clk_get_rate(*p);

	}

	*p_rate = rate;



	return f->freq;

}



static long clk_rcg2_determine_rate(struct clk_hw *hw, unsigned long rate,

		unsigned long *p_rate, struct clk **p)

{

	struct clk_rcg2 *rcg = to_clk_rcg2(hw);



	return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p);

}



static int __clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate)

{

	struct clk_rcg2 *rcg = to_clk_rcg2(hw);

	const struct freq_tbl *f;

	u32 cfg, mask;

	int ret;



	f = find_freq(rcg->freq_tbl, rate);

	if (!f)

		return -EINVAL;



	if (rcg->mnd_width && f->n) {

		mask = BIT(rcg->mnd_width) - 1;

		ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + M_REG,

					 mask, f->m);

		if (ret)

			return ret;



		ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + N_REG,

					 mask, ~(f->n - f->m));

		if (ret)

			return ret;



		ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + D_REG,

					 mask, ~f->n);

		if (ret)

			return ret;

	}



	mask = BIT(rcg->hid_width) - 1;

	mask |= CFG_SRC_SEL_MASK | CFG_MODE_MASK;

	cfg = f->pre_div << CFG_SRC_DIV_SHIFT;

	cfg |= rcg->parent_map[f->src] << CFG_SRC_SEL_SHIFT;

	if (rcg->mnd_width && f->n)

		cfg |= CFG_MODE_DUAL_EDGE;

	ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG, mask,

			cfg);

	if (ret)

		return ret;



	return update_config(rcg);

}



static int clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate,

			    unsigned long parent_rate)

{

	return __clk_rcg2_set_rate(hw, rate);

}



static int clk_rcg2_set_rate_and_parent(struct clk_hw *hw,

		unsigned long rate, unsigned long parent_rate, u8 index)

{

	return __clk_rcg2_set_rate(hw, rate);

}



const struct clk_ops clk_rcg2_ops = {

	.is_enabled = clk_rcg2_is_enabled,

	.get_parent = clk_rcg2_get_parent,

	.set_parent = clk_rcg2_set_parent,

	.recalc_rate = clk_rcg2_recalc_rate,

	.determine_rate = clk_rcg2_determine_rate,

	.set_rate = clk_rcg2_set_rate,

	.set_rate_and_parent = clk_rcg2_set_rate_and_parent,

};

EXPORT_SYMBOL_GPL(clk_rcg2_ops);

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