195 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			195 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0+
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| //
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| // OWL pll clock driver
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| //
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| // Copyright (c) 2014 Actions Semi Inc.
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| // Author: David Liu <liuwei@actions-semi.com>
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| //
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| // Copyright (c) 2018 Linaro Ltd.
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| // Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
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| 
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| #include <linux/clk-provider.h>
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| #include <linux/slab.h>
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| #include <linux/io.h>
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| #include <linux/delay.h>
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| 
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| #include "owl-pll.h"
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| 
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| static u32 owl_pll_calculate_mul(struct owl_pll_hw *pll_hw, unsigned long rate)
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| {
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| 	u32 mul;
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| 
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| 	mul = DIV_ROUND_CLOSEST(rate, pll_hw->bfreq);
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| 	if (mul < pll_hw->min_mul)
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| 		mul = pll_hw->min_mul;
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| 	else if (mul > pll_hw->max_mul)
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| 		mul = pll_hw->max_mul;
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| 
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| 	return mul & mul_mask(pll_hw);
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| }
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| 
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| static unsigned long _get_table_rate(const struct clk_pll_table *table,
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| 		unsigned int val)
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| {
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| 	const struct clk_pll_table *clkt;
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| 
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| 	for (clkt = table; clkt->rate; clkt++)
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| 		if (clkt->val == val)
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| 			return clkt->rate;
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| 
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| 	return 0;
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| }
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| 
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| static const struct clk_pll_table *_get_pll_table(
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| 		const struct clk_pll_table *table, unsigned long rate)
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| {
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| 	const struct clk_pll_table *clkt;
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| 
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| 	for (clkt = table; clkt->rate; clkt++) {
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| 		if (clkt->rate == rate) {
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| 			table = clkt;
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| 			break;
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| 		} else if (clkt->rate < rate)
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| 			table = clkt;
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| 	}
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| 
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| 	return table;
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| }
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| 
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| static long owl_pll_round_rate(struct clk_hw *hw, unsigned long rate,
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| 		unsigned long *parent_rate)
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| {
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| 	struct owl_pll *pll = hw_to_owl_pll(hw);
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| 	struct owl_pll_hw *pll_hw = &pll->pll_hw;
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| 	const struct clk_pll_table *clkt;
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| 	u32 mul;
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| 
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| 	if (pll_hw->table) {
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| 		clkt = _get_pll_table(pll_hw->table, rate);
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| 		return clkt->rate;
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| 	}
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| 
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| 	/* fixed frequency */
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| 	if (pll_hw->width == 0)
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| 		return pll_hw->bfreq;
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| 
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| 	mul = owl_pll_calculate_mul(pll_hw, rate);
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| 
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| 	return pll_hw->bfreq * mul;
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| }
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| 
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| static unsigned long owl_pll_recalc_rate(struct clk_hw *hw,
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| 		unsigned long parent_rate)
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| {
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| 	struct owl_pll *pll = hw_to_owl_pll(hw);
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| 	struct owl_pll_hw *pll_hw = &pll->pll_hw;
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| 	const struct owl_clk_common *common = &pll->common;
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| 	u32 val;
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| 
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| 	if (pll_hw->table) {
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| 		regmap_read(common->regmap, pll_hw->reg, &val);
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| 
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| 		val = val >> pll_hw->shift;
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| 		val &= mul_mask(pll_hw);
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| 
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| 		return _get_table_rate(pll_hw->table, val);
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| 	}
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| 
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| 	/* fixed frequency */
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| 	if (pll_hw->width == 0)
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| 		return pll_hw->bfreq;
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| 
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| 	regmap_read(common->regmap, pll_hw->reg, &val);
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| 
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| 	val = val >> pll_hw->shift;
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| 	val &= mul_mask(pll_hw);
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| 
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| 	return pll_hw->bfreq * val;
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| }
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| 
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| static int owl_pll_is_enabled(struct clk_hw *hw)
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| {
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| 	struct owl_pll *pll = hw_to_owl_pll(hw);
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| 	struct owl_pll_hw *pll_hw = &pll->pll_hw;
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| 	const struct owl_clk_common *common = &pll->common;
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| 	u32 reg;
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| 
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| 	regmap_read(common->regmap, pll_hw->reg, ®);
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| 
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| 	return !!(reg & BIT(pll_hw->bit_idx));
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| }
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| 
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| static void owl_pll_set(const struct owl_clk_common *common,
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| 		       const struct owl_pll_hw *pll_hw, bool enable)
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| {
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| 	u32 reg;
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| 
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| 	regmap_read(common->regmap, pll_hw->reg, ®);
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| 
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| 	if (enable)
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| 		reg |= BIT(pll_hw->bit_idx);
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| 	else
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| 		reg &= ~BIT(pll_hw->bit_idx);
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| 
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| 	regmap_write(common->regmap, pll_hw->reg, reg);
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| }
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| 
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| static int owl_pll_enable(struct clk_hw *hw)
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| {
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| 	struct owl_pll *pll = hw_to_owl_pll(hw);
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| 	const struct owl_clk_common *common = &pll->common;
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| 
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| 	owl_pll_set(common, &pll->pll_hw, true);
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| 
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| 	return 0;
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| }
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| 
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| static void owl_pll_disable(struct clk_hw *hw)
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| {
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| 	struct owl_pll *pll = hw_to_owl_pll(hw);
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| 	const struct owl_clk_common *common = &pll->common;
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| 
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| 	owl_pll_set(common, &pll->pll_hw, false);
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| }
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| 
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| static int owl_pll_set_rate(struct clk_hw *hw, unsigned long rate,
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| 		unsigned long parent_rate)
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| {
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| 	struct owl_pll *pll = hw_to_owl_pll(hw);
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| 	struct owl_pll_hw *pll_hw = &pll->pll_hw;
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| 	const struct owl_clk_common *common = &pll->common;
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| 	const struct clk_pll_table *clkt;
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| 	u32 val, reg;
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| 
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| 	/* fixed frequency */
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| 	if (pll_hw->width == 0)
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| 		return 0;
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| 
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| 	if (pll_hw->table) {
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| 		clkt = _get_pll_table(pll_hw->table, rate);
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| 		val = clkt->val;
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| 	} else {
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| 		val = owl_pll_calculate_mul(pll_hw, rate);
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| 	}
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| 
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| 	regmap_read(common->regmap, pll_hw->reg, ®);
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| 
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| 	reg &= ~mul_mask(pll_hw);
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| 	reg |= val << pll_hw->shift;
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| 
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| 	regmap_write(common->regmap, pll_hw->reg, reg);
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| 
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| 	udelay(pll_hw->delay);
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| 
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| 	return 0;
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| }
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| 
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| const struct clk_ops owl_pll_ops = {
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| 	.enable = owl_pll_enable,
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| 	.disable = owl_pll_disable,
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| 	.is_enabled = owl_pll_is_enabled,
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| 	.round_rate = owl_pll_round_rate,
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| 	.recalc_rate = owl_pll_recalc_rate,
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| 	.set_rate = owl_pll_set_rate,
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| };
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