https://github.com/torvalds/linux
Tip revision: 0e698dfa282211e414076f9dc7e83c1c288314fd authored by Linus Torvalds on 03 May 2020, 21:56:04 UTC
Linux 5.7-rc4
Linux 5.7-rc4
Tip revision: 0e698df
owl-pll.c
// SPDX-License-Identifier: GPL-2.0+
//
// OWL pll clock driver
//
// Copyright (c) 2014 Actions Semi Inc.
// Author: David Liu <liuwei@actions-semi.com>
//
// Copyright (c) 2018 Linaro Ltd.
// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
#include <linux/clk-provider.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/delay.h>
#include "owl-pll.h"
static u32 owl_pll_calculate_mul(struct owl_pll_hw *pll_hw, unsigned long rate)
{
u32 mul;
mul = DIV_ROUND_CLOSEST(rate, pll_hw->bfreq);
if (mul < pll_hw->min_mul)
mul = pll_hw->min_mul;
else if (mul > pll_hw->max_mul)
mul = pll_hw->max_mul;
return mul &= mul_mask(pll_hw);
}
static unsigned long _get_table_rate(const struct clk_pll_table *table,
unsigned int val)
{
const struct clk_pll_table *clkt;
for (clkt = table; clkt->rate; clkt++)
if (clkt->val == val)
return clkt->rate;
return 0;
}
static const struct clk_pll_table *_get_pll_table(
const struct clk_pll_table *table, unsigned long rate)
{
const struct clk_pll_table *clkt;
for (clkt = table; clkt->rate; clkt++) {
if (clkt->rate == rate) {
table = clkt;
break;
} else if (clkt->rate < rate)
table = clkt;
}
return table;
}
static long owl_pll_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
{
struct owl_pll *pll = hw_to_owl_pll(hw);
struct owl_pll_hw *pll_hw = &pll->pll_hw;
const struct clk_pll_table *clkt;
u32 mul;
if (pll_hw->table) {
clkt = _get_pll_table(pll_hw->table, rate);
return clkt->rate;
}
/* fixed frequency */
if (pll_hw->width == 0)
return pll_hw->bfreq;
mul = owl_pll_calculate_mul(pll_hw, rate);
return pll_hw->bfreq * mul;
}
static unsigned long owl_pll_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct owl_pll *pll = hw_to_owl_pll(hw);
struct owl_pll_hw *pll_hw = &pll->pll_hw;
const struct owl_clk_common *common = &pll->common;
u32 val;
if (pll_hw->table) {
regmap_read(common->regmap, pll_hw->reg, &val);
val = val >> pll_hw->shift;
val &= mul_mask(pll_hw);
return _get_table_rate(pll_hw->table, val);
}
/* fixed frequency */
if (pll_hw->width == 0)
return pll_hw->bfreq;
regmap_read(common->regmap, pll_hw->reg, &val);
val = val >> pll_hw->shift;
val &= mul_mask(pll_hw);
return pll_hw->bfreq * val;
}
static int owl_pll_is_enabled(struct clk_hw *hw)
{
struct owl_pll *pll = hw_to_owl_pll(hw);
struct owl_pll_hw *pll_hw = &pll->pll_hw;
const struct owl_clk_common *common = &pll->common;
u32 reg;
regmap_read(common->regmap, pll_hw->reg, ®);
return !!(reg & BIT(pll_hw->bit_idx));
}
static void owl_pll_set(const struct owl_clk_common *common,
const struct owl_pll_hw *pll_hw, bool enable)
{
u32 reg;
regmap_read(common->regmap, pll_hw->reg, ®);
if (enable)
reg |= BIT(pll_hw->bit_idx);
else
reg &= ~BIT(pll_hw->bit_idx);
regmap_write(common->regmap, pll_hw->reg, reg);
}
static int owl_pll_enable(struct clk_hw *hw)
{
struct owl_pll *pll = hw_to_owl_pll(hw);
const struct owl_clk_common *common = &pll->common;
owl_pll_set(common, &pll->pll_hw, true);
return 0;
}
static void owl_pll_disable(struct clk_hw *hw)
{
struct owl_pll *pll = hw_to_owl_pll(hw);
const struct owl_clk_common *common = &pll->common;
owl_pll_set(common, &pll->pll_hw, false);
}
static int owl_pll_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct owl_pll *pll = hw_to_owl_pll(hw);
struct owl_pll_hw *pll_hw = &pll->pll_hw;
const struct owl_clk_common *common = &pll->common;
const struct clk_pll_table *clkt;
u32 val, reg;
/* fixed frequency */
if (pll_hw->width == 0)
return 0;
if (pll_hw->table) {
clkt = _get_pll_table(pll_hw->table, rate);
val = clkt->val;
} else {
val = owl_pll_calculate_mul(pll_hw, rate);
}
regmap_read(common->regmap, pll_hw->reg, ®);
reg &= ~mul_mask(pll_hw);
reg |= val << pll_hw->shift;
regmap_write(common->regmap, pll_hw->reg, reg);
udelay(pll_hw->delay);
return 0;
}
const struct clk_ops owl_pll_ops = {
.enable = owl_pll_enable,
.disable = owl_pll_disable,
.is_enabled = owl_pll_is_enabled,
.round_rate = owl_pll_round_rate,
.recalc_rate = owl_pll_recalc_rate,
.set_rate = owl_pll_set_rate,
};