drivers/clk/qcom/clk-rcg2.c - kernel/lockdown - Git at Google

 /*
  * 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);
	/*
	* 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);