drivers/clk/qcom/clk-alpha-pll.c - kernel/quantenna - Git at Google

 /*
  * Copyright (c) 2015, 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/export.h>
 #include <linux/clk-provider.h>
 #include <linux/regmap.h>
 #include <linux/delay.h>

 #include "clk-alpha-pll.h"

 #define PLL_MODE		0x00
 # 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)
 # define PLL_ACTIVE_FLAG	BIT(30)
 # define PLL_LOCK_DET		BIT(31)

 #define PLL_L_VAL		0x04
 #define PLL_ALPHA_VAL		0x08
 #define PLL_ALPHA_VAL_U		0x0c

 #define PLL_USER_CTL		0x10
 # define PLL_POST_DIV_SHIFT	8
 # define PLL_POST_DIV_MASK	0xf
 # define PLL_ALPHA_EN		BIT(24)
 # define PLL_VCO_SHIFT		20
 # define PLL_VCO_MASK		0x3

 #define PLL_USER_CTL_U		0x14

 #define PLL_CONFIG_CTL		0x18
 #define PLL_TEST_CTL		0x1c
 #define PLL_TEST_CTL_U		0x20
 #define PLL_STATUS		0x24

 /*
  * Even though 40 bits are present, use only 32 for ease of calculation.
  */
 #define ALPHA_REG_BITWIDTH	40
 #define ALPHA_BITWIDTH		32

 #define to_clk_alpha_pll(_hw) container_of(to_clk_regmap(_hw), \
 					   struct clk_alpha_pll, clkr)

 #define to_clk_alpha_pll_postdiv(_hw) container_of(to_clk_regmap(_hw), \
 					   struct clk_alpha_pll_postdiv, clkr)

 static int wait_for_pll(struct clk_alpha_pll *pll)
 {
 	u32 val, mask, off;
 	int count;
 	int ret;
 	const char *name = clk_hw_get_name(&pll->clkr.hw);

 	off = pll->offset;
 	ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
 	if (ret)
 		return ret;

 	if (val & PLL_VOTE_FSM_ENA)
 		mask = PLL_ACTIVE_FLAG;
 	else
 		mask = PLL_LOCK_DET;

 	/* Wait for pll to enable. */
 	for (count = 100; count > 0; count--) {
 		ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
 		if (ret)
 			return ret;
 		if ((val & mask) == mask)
 			return 0;

 		udelay(1);
 	}

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

 static int clk_alpha_pll_enable(struct clk_hw *hw)
 {
 	int ret;
 	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
 	u32 val, mask, off;

 	off = pll->offset;

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

 	/* If in FSM mode, just vote for it */
 	if (val & PLL_VOTE_FSM_ENA) {
 		ret = clk_enable_regmap(hw);
 		if (ret)
 			return ret;
 		return wait_for_pll(pll);
 	}

 	/* Skip if already enabled */
 	if ((val & mask) == mask)
 		return 0;

 	ret = regmap_update_bits(pll->clkr.regmap, off + PLL_MODE,
 				 PLL_BYPASSNL, PLL_BYPASSNL);
 	if (ret)
 		return ret;

 	/*
 	 * H/W requires a 5us delay between disabling the bypass and
 	 * de-asserting the reset.
 	 */
 	mb();
 	udelay(5);

 	ret = regmap_update_bits(pll->clkr.regmap, off + PLL_MODE,
 				 PLL_RESET_N, PLL_RESET_N);
 	if (ret)
 		return ret;

 	ret = wait_for_pll(pll);
 	if (ret)
 		return ret;

 	ret = regmap_update_bits(pll->clkr.regmap, off + PLL_MODE,
 				 PLL_OUTCTRL, PLL_OUTCTRL);

 	/* Ensure that the write above goes through before returning. */
 	mb();
 	return ret;
 }

 static void clk_alpha_pll_disable(struct clk_hw *hw)
 {
 	int ret;
 	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
 	u32 val, mask, off;

 	off = pll->offset;

 	ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
 	if (ret)
 		return;

 	/* If in FSM mode, just unvote it */
 	if (val & PLL_VOTE_FSM_ENA) {
 		clk_disable_regmap(hw);
 		return;
 	}

 	mask = PLL_OUTCTRL;
 	regmap_update_bits(pll->clkr.regmap, off + PLL_MODE, mask, 0);

 	/* Delay of 2 output clock ticks required until output is disabled */
 	mb();
 	udelay(1);

 	mask = PLL_RESET_N | PLL_BYPASSNL;
 	regmap_update_bits(pll->clkr.regmap, off + PLL_MODE, mask, 0);
 }

 static unsigned long alpha_pll_calc_rate(u64 prate, u32 l, u32 a)
 {
 	return (prate * l) + ((prate * a) >> ALPHA_BITWIDTH);
 }

 static unsigned long
 alpha_pll_round_rate(unsigned long rate, unsigned long prate, u32 *l, u64 *a)
 {
 	u64 remainder;
 	u64 quotient;

 	quotient = rate;
 	remainder = do_div(quotient, prate);
 	*l = quotient;

 	if (!remainder) {
 		*a = 0;
 		return rate;
 	}

 	/* Upper ALPHA_BITWIDTH bits of Alpha */
 	quotient = remainder << ALPHA_BITWIDTH;
 	remainder = do_div(quotient, prate);

 	if (remainder)
 		quotient++;

 	*a = quotient;
 	return alpha_pll_calc_rate(prate, *l, *a);
 }

 static const struct pll_vco *
 alpha_pll_find_vco(const struct clk_alpha_pll *pll, unsigned long rate)
 {
 	const struct pll_vco *v = pll->vco_table;
 	const struct pll_vco *end = v + pll->num_vco;

 	for (; v < end; v++)
 		if (rate >= v->min_freq && rate <= v->max_freq)
 			return v;

 	return NULL;
 }

 static unsigned long
 clk_alpha_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
 {
 	u32 l, low, high, ctl;
 	u64 a = 0, prate = parent_rate;
 	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
 	u32 off = pll->offset;

 	regmap_read(pll->clkr.regmap, off + PLL_L_VAL, &l);

 	regmap_read(pll->clkr.regmap, off + PLL_USER_CTL, &ctl);
 	if (ctl & PLL_ALPHA_EN) {
 		regmap_read(pll->clkr.regmap, off + PLL_ALPHA_VAL, &low);
 		regmap_read(pll->clkr.regmap, off + PLL_ALPHA_VAL_U, &high);
 		a = (u64)high << 32 | low;
 		a >>= ALPHA_REG_BITWIDTH - ALPHA_BITWIDTH;
 	}

 	return alpha_pll_calc_rate(prate, l, a);
 }

 static int clk_alpha_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 				  unsigned long prate)
 {
 	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
 	const struct pll_vco *vco;
 	u32 l, off = pll->offset;
 	u64 a;

 	rate = alpha_pll_round_rate(rate, prate, &l, &a);
 	vco = alpha_pll_find_vco(pll, rate);
 	if (!vco) {
 		pr_err("alpha pll not in a valid vco range\n");
 		return -EINVAL;
 	}

 	a <<= (ALPHA_REG_BITWIDTH - ALPHA_BITWIDTH);

 	regmap_write(pll->clkr.regmap, off + PLL_L_VAL, l);
 	regmap_write(pll->clkr.regmap, off + PLL_ALPHA_VAL, a);
 	regmap_write(pll->clkr.regmap, off + PLL_ALPHA_VAL_U, a >> 32);

 	regmap_update_bits(pll->clkr.regmap, off + PLL_USER_CTL,
 			   PLL_VCO_MASK << PLL_VCO_SHIFT,
 			   vco->val << PLL_VCO_SHIFT);

 	regmap_update_bits(pll->clkr.regmap, off + PLL_USER_CTL, PLL_ALPHA_EN,
 			   PLL_ALPHA_EN);

 	return 0;
 }

 static long clk_alpha_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 				     unsigned long *prate)
 {
 	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
 	u32 l;
 	u64 a;
 	unsigned long min_freq, max_freq;

 	rate = alpha_pll_round_rate(rate, *prate, &l, &a);
 	if (alpha_pll_find_vco(pll, rate))
 		return rate;

 	min_freq = pll->vco_table[0].min_freq;
 	max_freq = pll->vco_table[pll->num_vco - 1].max_freq;

 	return clamp(rate, min_freq, max_freq);
 }

 const struct clk_ops clk_alpha_pll_ops = {
 	.enable = clk_alpha_pll_enable,
 	.disable = clk_alpha_pll_disable,
 	.recalc_rate = clk_alpha_pll_recalc_rate,
 	.round_rate = clk_alpha_pll_round_rate,
 	.set_rate = clk_alpha_pll_set_rate,
 };
 EXPORT_SYMBOL_GPL(clk_alpha_pll_ops);

 static unsigned long
 clk_alpha_pll_postdiv_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
 {
 	struct clk_alpha_pll_postdiv *pll = to_clk_alpha_pll_postdiv(hw);
 	u32 ctl;

 	regmap_read(pll->clkr.regmap, pll->offset + PLL_USER_CTL, &ctl);

 	ctl >>= PLL_POST_DIV_SHIFT;
 	ctl &= PLL_POST_DIV_MASK;

 	return parent_rate >> fls(ctl);
 }

 static const struct clk_div_table clk_alpha_div_table[] = {
 	{ 0x0, 1 },
 	{ 0x1, 2 },
 	{ 0x3, 4 },
 	{ 0x7, 8 },
 	{ 0xf, 16 },
 	{ }
 };

 static long
 clk_alpha_pll_postdiv_round_rate(struct clk_hw *hw, unsigned long rate,
 				 unsigned long *prate)
 {
 	struct clk_alpha_pll_postdiv *pll = to_clk_alpha_pll_postdiv(hw);

 	return divider_round_rate(hw, rate, prate, clk_alpha_div_table,
 				  pll->width, CLK_DIVIDER_POWER_OF_TWO);
 }

 static int clk_alpha_pll_postdiv_set_rate(struct clk_hw *hw, unsigned long rate,
 					  unsigned long parent_rate)
 {
 	struct clk_alpha_pll_postdiv *pll = to_clk_alpha_pll_postdiv(hw);
 	int div;

 	/* 16 -> 0xf, 8 -> 0x7, 4 -> 0x3, 2 -> 0x1, 1 -> 0x0 */
 	div = DIV_ROUND_UP_ULL((u64)parent_rate, rate) - 1;

 	return regmap_update_bits(pll->clkr.regmap, pll->offset + PLL_USER_CTL,
 				  PLL_POST_DIV_MASK << PLL_POST_DIV_SHIFT,
 				  div << PLL_POST_DIV_SHIFT);
 }

 const struct clk_ops clk_alpha_pll_postdiv_ops = {
 	.recalc_rate = clk_alpha_pll_postdiv_recalc_rate,
 	.round_rate = clk_alpha_pll_postdiv_round_rate,
 	.set_rate = clk_alpha_pll_postdiv_set_rate,
 };
 EXPORT_SYMBOL_GPL(clk_alpha_pll_postdiv_ops);
	/*
	* Copyright (c) 2015, 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/export.h>
	#include <linux/clk-provider.h>
	#include <linux/regmap.h>
	#include <linux/delay.h>

	#include "clk-alpha-pll.h"

	#define PLL_MODE 0x00
	# 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)
	# define PLL_ACTIVE_FLAG BIT(30)
	# define PLL_LOCK_DET BIT(31)

	#define PLL_L_VAL 0x04
	#define PLL_ALPHA_VAL 0x08
	#define PLL_ALPHA_VAL_U 0x0c

	#define PLL_USER_CTL 0x10
	# define PLL_POST_DIV_SHIFT 8
	# define PLL_POST_DIV_MASK 0xf
	# define PLL_ALPHA_EN BIT(24)
	# define PLL_VCO_SHIFT 20
	# define PLL_VCO_MASK 0x3

	#define PLL_USER_CTL_U 0x14

	#define PLL_CONFIG_CTL 0x18
	#define PLL_TEST_CTL 0x1c
	#define PLL_TEST_CTL_U 0x20
	#define PLL_STATUS 0x24

	/*
	* Even though 40 bits are present, use only 32 for ease of calculation.
	*/
	#define ALPHA_REG_BITWIDTH 40
	#define ALPHA_BITWIDTH 32

	#define to_clk_alpha_pll(_hw) container_of(to_clk_regmap(_hw), \
	struct clk_alpha_pll, clkr)

	#define to_clk_alpha_pll_postdiv(_hw) container_of(to_clk_regmap(_hw), \
	struct clk_alpha_pll_postdiv, clkr)

	static int wait_for_pll(struct clk_alpha_pll *pll)
	{
	u32 val, mask, off;
	int count;
	int ret;
	const char *name = clk_hw_get_name(&pll->clkr.hw);

	off = pll->offset;
	ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
	if (ret)
	return ret;

	if (val & PLL_VOTE_FSM_ENA)
	mask = PLL_ACTIVE_FLAG;
	else
	mask = PLL_LOCK_DET;

	/* Wait for pll to enable. */
	for (count = 100; count > 0; count--) {
	ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
	if (ret)
	return ret;
	if ((val & mask) == mask)
	return 0;

	udelay(1);
	}

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

	static int clk_alpha_pll_enable(struct clk_hw *hw)
	{
	int ret;
	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
	u32 val, mask, off;

	off = pll->offset;

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

	/* If in FSM mode, just vote for it */
	if (val & PLL_VOTE_FSM_ENA) {
	ret = clk_enable_regmap(hw);
	if (ret)
	return ret;
	return wait_for_pll(pll);
	}

	/* Skip if already enabled */
	if ((val & mask) == mask)
	return 0;

	ret = regmap_update_bits(pll->clkr.regmap, off + PLL_MODE,
	PLL_BYPASSNL, PLL_BYPASSNL);
	if (ret)
	return ret;

	/*
	* H/W requires a 5us delay between disabling the bypass and
	* de-asserting the reset.
	*/
	mb();
	udelay(5);

	ret = regmap_update_bits(pll->clkr.regmap, off + PLL_MODE,
	PLL_RESET_N, PLL_RESET_N);
	if (ret)
	return ret;

	ret = wait_for_pll(pll);
	if (ret)
	return ret;

	ret = regmap_update_bits(pll->clkr.regmap, off + PLL_MODE,
	PLL_OUTCTRL, PLL_OUTCTRL);

	/* Ensure that the write above goes through before returning. */
	mb();
	return ret;
	}

	static void clk_alpha_pll_disable(struct clk_hw *hw)
	{
	int ret;
	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
	u32 val, mask, off;

	off = pll->offset;

	ret = regmap_read(pll->clkr.regmap, off + PLL_MODE, &val);
	if (ret)
	return;

	/* If in FSM mode, just unvote it */
	if (val & PLL_VOTE_FSM_ENA) {
	clk_disable_regmap(hw);
	return;
	}

	mask = PLL_OUTCTRL;
	regmap_update_bits(pll->clkr.regmap, off + PLL_MODE, mask, 0);

	/* Delay of 2 output clock ticks required until output is disabled */
	mb();
	udelay(1);

	mask = PLL_RESET_N \| PLL_BYPASSNL;
	regmap_update_bits(pll->clkr.regmap, off + PLL_MODE, mask, 0);
	}

	static unsigned long alpha_pll_calc_rate(u64 prate, u32 l, u32 a)
	{
	return (prate * l) + ((prate * a) >> ALPHA_BITWIDTH);
	}

	static unsigned long
	alpha_pll_round_rate(unsigned long rate, unsigned long prate, u32 l, u64 a)
	{
	u64 remainder;
	u64 quotient;

	quotient = rate;
	remainder = do_div(quotient, prate);
	*l = quotient;

	if (!remainder) {
	*a = 0;
	return rate;
	}

	/* Upper ALPHA_BITWIDTH bits of Alpha */
	quotient = remainder << ALPHA_BITWIDTH;
	remainder = do_div(quotient, prate);

	if (remainder)
	quotient++;

	*a = quotient;
	return alpha_pll_calc_rate(prate, l, a);
	}

	static const struct pll_vco *
	alpha_pll_find_vco(const struct clk_alpha_pll *pll, unsigned long rate)
	{
	const struct pll_vco *v = pll->vco_table;
	const struct pll_vco *end = v + pll->num_vco;

	for (; v < end; v++)
	if (rate >= v->min_freq && rate <= v->max_freq)
	return v;

	return NULL;
	}

	static unsigned long
	clk_alpha_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
	{
	u32 l, low, high, ctl;
	u64 a = 0, prate = parent_rate;
	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
	u32 off = pll->offset;

	regmap_read(pll->clkr.regmap, off + PLL_L_VAL, &l);

	regmap_read(pll->clkr.regmap, off + PLL_USER_CTL, &ctl);
	if (ctl & PLL_ALPHA_EN) {
	regmap_read(pll->clkr.regmap, off + PLL_ALPHA_VAL, &low);
	regmap_read(pll->clkr.regmap, off + PLL_ALPHA_VAL_U, &high);
	a = (u64)high << 32 \| low;
	a >>= ALPHA_REG_BITWIDTH - ALPHA_BITWIDTH;
	}

	return alpha_pll_calc_rate(prate, l, a);
	}

	static int clk_alpha_pll_set_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long prate)
	{
	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
	const struct pll_vco *vco;
	u32 l, off = pll->offset;
	u64 a;

	rate = alpha_pll_round_rate(rate, prate, &l, &a);
	vco = alpha_pll_find_vco(pll, rate);
	if (!vco) {
	pr_err("alpha pll not in a valid vco range\n");
	return -EINVAL;
	}

	a <<= (ALPHA_REG_BITWIDTH - ALPHA_BITWIDTH);

	regmap_write(pll->clkr.regmap, off + PLL_L_VAL, l);
	regmap_write(pll->clkr.regmap, off + PLL_ALPHA_VAL, a);
	regmap_write(pll->clkr.regmap, off + PLL_ALPHA_VAL_U, a >> 32);

	regmap_update_bits(pll->clkr.regmap, off + PLL_USER_CTL,
	PLL_VCO_MASK << PLL_VCO_SHIFT,
	vco->val << PLL_VCO_SHIFT);

	regmap_update_bits(pll->clkr.regmap, off + PLL_USER_CTL, PLL_ALPHA_EN,
	PLL_ALPHA_EN);

	return 0;
	}

	static long clk_alpha_pll_round_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long *prate)
	{
	struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
	u32 l;
	u64 a;
	unsigned long min_freq, max_freq;

	rate = alpha_pll_round_rate(rate, *prate, &l, &a);
	if (alpha_pll_find_vco(pll, rate))
	return rate;

	min_freq = pll->vco_table[0].min_freq;
	max_freq = pll->vco_table[pll->num_vco - 1].max_freq;

	return clamp(rate, min_freq, max_freq);
	}

	const struct clk_ops clk_alpha_pll_ops = {
	.enable = clk_alpha_pll_enable,
	.disable = clk_alpha_pll_disable,
	.recalc_rate = clk_alpha_pll_recalc_rate,
	.round_rate = clk_alpha_pll_round_rate,
	.set_rate = clk_alpha_pll_set_rate,
	};
	EXPORT_SYMBOL_GPL(clk_alpha_pll_ops);

	static unsigned long
	clk_alpha_pll_postdiv_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
	{
	struct clk_alpha_pll_postdiv *pll = to_clk_alpha_pll_postdiv(hw);
	u32 ctl;

	regmap_read(pll->clkr.regmap, pll->offset + PLL_USER_CTL, &ctl);

	ctl >>= PLL_POST_DIV_SHIFT;
	ctl &= PLL_POST_DIV_MASK;

	return parent_rate >> fls(ctl);
	}

	static const struct clk_div_table clk_alpha_div_table[] = {
	{ 0x0, 1 },
	{ 0x1, 2 },
	{ 0x3, 4 },
	{ 0x7, 8 },
	{ 0xf, 16 },
	{ }
	};

	static long
	clk_alpha_pll_postdiv_round_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long *prate)
	{
	struct clk_alpha_pll_postdiv *pll = to_clk_alpha_pll_postdiv(hw);

	return divider_round_rate(hw, rate, prate, clk_alpha_div_table,
	pll->width, CLK_DIVIDER_POWER_OF_TWO);
	}

	static int clk_alpha_pll_postdiv_set_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long parent_rate)
	{
	struct clk_alpha_pll_postdiv *pll = to_clk_alpha_pll_postdiv(hw);
	int div;

	/* 16 -> 0xf, 8 -> 0x7, 4 -> 0x3, 2 -> 0x1, 1 -> 0x0 */
	div = DIV_ROUND_UP_ULL((u64)parent_rate, rate) - 1;

	return regmap_update_bits(pll->clkr.regmap, pll->offset + PLL_USER_CTL,
	PLL_POST_DIV_MASK << PLL_POST_DIV_SHIFT,
	div << PLL_POST_DIV_SHIFT);
	}

	const struct clk_ops clk_alpha_pll_postdiv_ops = {
	.recalc_rate = clk_alpha_pll_postdiv_recalc_rate,
	.round_rate = clk_alpha_pll_postdiv_round_rate,
	.set_rate = clk_alpha_pll_postdiv_set_rate,
	};
	EXPORT_SYMBOL_GPL(clk_alpha_pll_postdiv_ops);