Commit 6174a1e2 authored by Maxime Ripard's avatar Maxime Ripard Committed by Michael Turquette

clk: sunxi-ng: Add N-M-factor clock support

Introduce support for clocks that multiply and divide using linear factors.
Signed-off-by: default avatarMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: default avatarMichael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20160629190535.11855-11-maxime.ripard@free-electrons.com
parent adbfb005
......@@ -28,6 +28,12 @@ config SUNXI_CCU_NK
bool
select SUNXI_CCU_GATE
config SUNXI_CCU_NM
bool
select RATIONAL
select SUNXI_CCU_FRAC
select SUNXI_CCU_GATE
config SUNXI_CCU_MP
bool
select SUNXI_CCU_GATE
......
......@@ -11,4 +11,5 @@ obj-$(CONFIG_SUNXI_CCU_PHASE) += ccu_phase.o
# Multi-factor clocks
obj-$(CONFIG_SUNXI_CCU_NK) += ccu_nk.o
obj-$(CONFIG_SUNXI_CCU_NM) += ccu_nm.o
obj-$(CONFIG_SUNXI_CCU_MP) += ccu_mp.o
/*
* Copyright (C) 2016 Maxime Ripard
* Maxime Ripard <maxime.ripard@free-electrons.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*/
#include <linux/clk-provider.h>
#include <linux/rational.h>
#include "ccu_frac.h"
#include "ccu_gate.h"
#include "ccu_nm.h"
static void ccu_nm_disable(struct clk_hw *hw)
{
struct ccu_nm *nm = hw_to_ccu_nm(hw);
return ccu_gate_helper_disable(&nm->common, nm->enable);
}
static int ccu_nm_enable(struct clk_hw *hw)
{
struct ccu_nm *nm = hw_to_ccu_nm(hw);
return ccu_gate_helper_enable(&nm->common, nm->enable);
}
static int ccu_nm_is_enabled(struct clk_hw *hw)
{
struct ccu_nm *nm = hw_to_ccu_nm(hw);
return ccu_gate_helper_is_enabled(&nm->common, nm->enable);
}
static unsigned long ccu_nm_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct ccu_nm *nm = hw_to_ccu_nm(hw);
unsigned long n, m;
u32 reg;
if (ccu_frac_helper_is_enabled(&nm->common, &nm->frac))
return ccu_frac_helper_read_rate(&nm->common, &nm->frac);
reg = readl(nm->common.base + nm->common.reg);
n = reg >> nm->n.shift;
n &= (1 << nm->n.width) - 1;
m = reg >> nm->m.shift;
m &= (1 << nm->m.width) - 1;
return parent_rate * (n + 1) / (m + 1);
}
static long ccu_nm_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
{
struct ccu_nm *nm = hw_to_ccu_nm(hw);
unsigned long n, m;
rational_best_approximation(rate, *parent_rate,
1 << nm->n.width, 1 << nm->m.width,
&n, &m);
return *parent_rate * n / m;
}
static int ccu_nm_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct ccu_nm *nm = hw_to_ccu_nm(hw);
unsigned long flags;
unsigned long n, m;
u32 reg;
if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate))
return ccu_frac_helper_set_rate(&nm->common, &nm->frac, rate);
else
ccu_frac_helper_disable(&nm->common, &nm->frac);
rational_best_approximation(rate, parent_rate,
1 << nm->n.width, 1 << nm->m.width,
&n, &m);
spin_lock_irqsave(nm->common.lock, flags);
reg = readl(nm->common.base + nm->common.reg);
reg &= ~GENMASK(nm->n.width + nm->n.shift - 1, nm->n.shift);
reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift);
writel(reg | ((m - 1) << nm->m.shift) | ((n - 1) << nm->n.shift),
nm->common.base + nm->common.reg);
spin_unlock_irqrestore(nm->common.lock, flags);
ccu_helper_wait_for_lock(&nm->common, nm->lock);
return 0;
}
const struct clk_ops ccu_nm_ops = {
.disable = ccu_nm_disable,
.enable = ccu_nm_enable,
.is_enabled = ccu_nm_is_enabled,
.recalc_rate = ccu_nm_recalc_rate,
.round_rate = ccu_nm_round_rate,
.set_rate = ccu_nm_set_rate,
};
/*
* Copyright (c) 2016 Maxime Ripard. 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 _CCU_NM_H_
#define _CCU_NM_H_
#include <linux/clk-provider.h>
#include "ccu_common.h"
#include "ccu_div.h"
#include "ccu_frac.h"
#include "ccu_mult.h"
/*
* struct ccu_nm - Definition of an N-M clock
*
* Clocks based on the formula parent * N / M
*/
struct ccu_nm {
u32 enable;
u32 lock;
struct _ccu_mult n;
struct _ccu_div m;
struct _ccu_frac frac;
struct ccu_common common;
};
#define SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK(_struct, _name, _parent, _reg, \
_nshift, _nwidth, \
_mshift, _mwidth, \
_frac_en, _frac_sel, \
_frac_rate_0, _frac_rate_1, \
_gate, _lock, _flags) \
struct ccu_nm _struct = { \
.enable = _gate, \
.lock = _lock, \
.n = _SUNXI_CCU_MULT(_nshift, _nwidth), \
.m = _SUNXI_CCU_DIV(_mshift, _mwidth), \
.frac = _SUNXI_CCU_FRAC(_frac_en, _frac_sel, \
_frac_rate_0, \
_frac_rate_1), \
.common = { \
.reg = _reg, \
.features = CCU_FEATURE_FRACTIONAL, \
.hw.init = CLK_HW_INIT(_name, \
_parent, \
&ccu_nm_ops, \
_flags), \
}, \
}
#define SUNXI_CCU_NM_WITH_GATE_LOCK(_struct, _name, _parent, _reg, \
_nshift, _nwidth, \
_mshift, _mwidth, \
_gate, _lock, _flags) \
struct ccu_nm _struct = { \
.enable = _gate, \
.lock = _lock, \
.n = _SUNXI_CCU_MULT(_nshift, _nwidth), \
.m = _SUNXI_CCU_DIV(_mshift, _mwidth), \
.common = { \
.reg = _reg, \
.hw.init = CLK_HW_INIT(_name, \
_parent, \
&ccu_nm_ops, \
_flags), \
}, \
}
static inline struct ccu_nm *hw_to_ccu_nm(struct clk_hw *hw)
{
struct ccu_common *common = hw_to_ccu_common(hw);
return container_of(common, struct ccu_nm, common);
}
extern const struct clk_ops ccu_nm_ops;
#endif /* _CCU_NM_H_ */
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