// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2011 Sascha Hauer, Pengutronix <[email protected]>
* Copyright (C) 2011 Richard Zhao, Linaro <[email protected]>
* Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <[email protected]>
*
* Simple multiplexer clock implementation
*/
#include <linux/clk-provider.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/err.h>
/*
* DOC: basic adjustable multiplexer clock that cannot gate
*
* Traits of this clock:
* prepare - clk_prepare only ensures that parents are prepared
* enable - clk_enable only ensures that parents are enabled
* rate - rate is only affected by parent switching. No clk_set_rate support
* parent - parent is adjustable through clk_set_parent
*/
static inline u32 clk_mux_readl(struct clk_mux *mux)
{
if (mux->flags & CLK_MUX_BIG_ENDIAN)
return ioread32be(mux->reg);
return readl(mux->reg);
}
static inline void clk_mux_writel(struct clk_mux *mux, u32 val)
{
if (mux->flags & CLK_MUX_BIG_ENDIAN)
iowrite32be(val, mux->reg);
else
writel(val, mux->reg);
}
int clk_mux_val_to_index(struct clk_hw *hw, const u32 *table, unsigned int flags,
unsigned int val)
{
int num_parents = clk_hw_get_num_parents(hw);
if (table) {
int i;
for (i = 0; i < num_parents; i++)
if (table[i] == val)
return i;
return -EINVAL;
}
if (val && (flags & CLK_MUX_INDEX_BIT))
val = ffs(val) - 1;
if (val && (flags & CLK_MUX_INDEX_ONE))
val--;
if (val >= num_parents)
return -EINVAL;
return val;
}
EXPORT_SYMBOL_GPL(clk_mux_val_to_index);
unsigned int clk_mux_index_to_val(const u32 *table, unsigned int flags, u8 index)
{
unsigned int val = index;
if (table) {
val = table[index];
} else {
if (flags & CLK_MUX_INDEX_BIT)
val = 1 << index;
if (flags & CLK_MUX_INDEX_ONE)
val++;
}
return val;
}
EXPORT_SYMBOL_GPL(clk_mux_index_to_val);
static u8 clk_mux_get_parent(struct clk_hw *hw)
{
struct clk_mux *mux = to_clk_mux(hw);
u32 val;
val = clk_mux_readl(mux) >> mux->shift;
val &= mux->mask;
return clk_mux_val_to_index(hw, mux->table, mux->flags, val);
}
static int clk_mux_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_mux *mux = to_clk_mux(hw);
u32 val = clk_mux_index_to_val(mux->table, mux->flags, index);
unsigned long flags = 0;
u32 reg;
if (mux->lock)
spin_lock_irqsave(mux->lock, flags);
else
__acquire(mux->lock);
if (mux->flags & CLK_MUX_HIWORD_MASK) {
reg = mux->mask << (mux->shift + 16);
} else {
reg = clk_mux_readl(mux);
reg &= ~(mux->mask << mux->shift);
}
val = val << mux->shift;
reg |= val;
clk_mux_writel(mux, reg);
if (mux->lock)
spin_unlock_irqrestore(mux->lock, flags);
else
__release(mux->lock);
return 0;
}
static int clk_mux_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct clk_mux *mux = to_clk_mux(hw);
return clk_mux_determine_rate_flags(hw, req, mux->flags);
}
const struct clk_ops clk_mux_ops = {
.get_parent = clk_mux_get_parent,
.set_parent = clk_mux_set_parent,
.determine_rate = clk_mux_determine_rate,
};
EXPORT_SYMBOL_GPL(clk_mux_ops);
const struct clk_ops clk_mux_ro_ops = {
.get_parent = clk_mux_get_parent,
};
EXPORT_SYMBOL_GPL(clk_mux_ro_ops);
struct clk_hw *__clk_hw_register_mux(struct device *dev, struct device_node *np,
const char *name, u8 num_parents,
const char * const *parent_names,
const struct clk_hw **parent_hws,
const struct clk_parent_data *parent_data,
unsigned long flags, void __iomem *reg, u8 shift, u32 mask,
u8 clk_mux_flags, const u32 *table, spinlock_t *lock)
{
struct clk_mux *mux;
struct clk_hw *hw;
struct clk_init_data init = {};
int ret = -EINVAL;
if (clk_mux_flags & CLK_MUX_HIWORD_MASK) {
u8 width = fls(mask) - ffs(mask) + 1;
if (width + shift > 16) {
pr_err("mux value exceeds LOWORD field\n");
return ERR_PTR(-EINVAL);
}
}
/* allocate the mux */
mux = kzalloc(sizeof(*mux), GFP_KERNEL);
if (!mux)
return ERR_PTR(-ENOMEM);
init.name = name;
if (clk_mux_flags & CLK_MUX_READ_ONLY)
init.ops = &clk_mux_ro_ops;
else
init.ops = &clk_mux_ops;
init.flags = flags;
init.parent_names = parent_names;
init.parent_data = parent_data;
init.parent_hws = parent_hws;
init.num_parents = num_parents;
/* struct clk_mux assignments */
mux->reg = reg;
mux->shift = shift;
mux->mask = mask;
mux->flags = clk_mux_flags;
mux->lock = lock;
mux->table = table;
mux->hw.init = &init;
hw = &mux->hw;
if (dev || !np)
ret = clk_hw_register(dev, hw);
else if (np)
ret = of_clk_hw_register(np, hw);
if (ret) {
kfree(mux);
hw = ERR_PTR(ret);
}
return hw;
}
EXPORT_SYMBOL_GPL(__clk_hw_register_mux);
static void devm_clk_hw_release_mux(struct device *dev, void *res)
{
clk_hw_unregister_mux(*(struct clk_hw **)res);
}
struct clk_hw *__devm_clk_hw_register_mux(struct device *dev, struct device_node *np,
const char *name, u8 num_parents,
const char * const *parent_names,
const struct clk_hw **parent_hws,
const struct clk_parent_data *parent_data,
unsigned long flags, void __iomem *reg, u8 shift, u32 mask,
u8 clk_mux_flags, const u32 *table, spinlock_t *lock)
{
struct clk_hw **ptr, *hw;
ptr = devres_alloc(devm_clk_hw_release_mux, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
hw = __clk_hw_register_mux(dev, np, name, num_parents, parent_names, parent_hws,
parent_data, flags, reg, shift, mask,
clk_mux_flags, table, lock);
if (!IS_ERR(hw)) {
*ptr = hw;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return hw;
}
EXPORT_SYMBOL_GPL(__devm_clk_hw_register_mux);
struct clk *clk_register_mux_table(struct device *dev, const char *name,
const char * const *parent_names, u8 num_parents,
unsigned long flags, void __iomem *reg, u8 shift, u32 mask,
u8 clk_mux_flags, const u32 *table, spinlock_t *lock)
{
struct clk_hw *hw;
hw = clk_hw_register_mux_table(dev, name, parent_names,
num_parents, flags, reg, shift, mask,
clk_mux_flags, table, lock);
if (IS_ERR(hw))
return ERR_CAST(hw);
return hw->clk;
}
EXPORT_SYMBOL_GPL(clk_register_mux_table);
void clk_unregister_mux(struct clk *clk)
{
struct clk_mux *mux;
struct clk_hw *hw;
hw = __clk_get_hw(clk);
if (!hw)
return;
mux = to_clk_mux(hw);
clk_unregister(clk);
kfree(mux);
}
EXPORT_SYMBOL_GPL(clk_unregister_mux);
void clk_hw_unregister_mux(struct clk_hw *hw)
{
struct clk_mux *mux;
mux = to_clk_mux(hw);
clk_hw_unregister(hw);
kfree(mux);
}
EXPORT_SYMBOL_GPL(clk_hw_unregister_mux);
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