- 根目录:
- drivers
- clk
- mmp
- clk-mix.c
/*
* mmp mix(div and mux) clock operation source file
*
* Copyright (C) 2014 Marvell
* Chao Xie <chao.xie@marvell.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/clk-provider.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/err.h>
#include "clk.h"
/*
* The mix clock is a clock combined mux and div type clock.
* Because the div field and mux field need to be set at same
* time, we can not divide it into 2 types of clock
*/
#define to_clk_mix(hw) container_of(hw, struct mmp_clk_mix, hw)
static unsigned int _get_maxdiv(struct mmp_clk_mix *mix)
{
unsigned int div_mask = (1 << mix->reg_info.width_div) - 1;
unsigned int maxdiv = 0;
struct clk_div_table *clkt;
if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
return div_mask;
if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
return 1 << div_mask;
if (mix->div_table) {
for (clkt = mix->div_table; clkt->div; clkt++)
if (clkt->div > maxdiv)
maxdiv = clkt->div;
return maxdiv;
}
return div_mask + 1;
}
static unsigned int _get_div(struct mmp_clk_mix *mix, unsigned int val)
{
struct clk_div_table *clkt;
if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
return val;
if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
return 1 << val;
if (mix->div_table) {
for (clkt = mix->div_table; clkt->div; clkt++)
if (clkt->val == val)
return clkt->div;
if (clkt->div == 0)
return 0;
}
return val + 1;
}
static unsigned int _get_mux(struct mmp_clk_mix *mix, unsigned int val)
{
int num_parents = __clk_get_num_parents(mix->hw.clk);
int i;
if (mix->mux_flags & CLK_MUX_INDEX_BIT)
return ffs(val) - 1;
if (mix->mux_flags & CLK_MUX_INDEX_ONE)
return val - 1;
if (mix->mux_table) {
for (i = 0; i < num_parents; i++)
if (mix->mux_table[i] == val)
return i;
if (i == num_parents)
return 0;
}
return val;
}
static unsigned int _get_div_val(struct mmp_clk_mix *mix, unsigned int div)
{
struct clk_div_table *clkt;
if (mix->div_flags & CLK_DIVIDER_ONE_BASED)
return div;
if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO)
return __ffs(div);
if (mix->div_table) {
for (clkt = mix->div_table; clkt->div; clkt++)
if (clkt->div == div)
return clkt->val;
if (clkt->div == 0)
return 0;
}
return div - 1;
}
static unsigned int _get_mux_val(struct mmp_clk_mix *mix, unsigned int mux)
{
if (mix->mux_table)
return mix->mux_table[mux];
return mux;
}
static void _filter_clk_table(struct mmp_clk_mix *mix,
struct mmp_clk_mix_clk_table *table,
unsigned int table_size)
{
int i;
struct mmp_clk_mix_clk_table *item;
struct clk *parent, *clk;
unsigned long parent_rate;
clk = mix->hw.clk;
for (i = 0; i < table_size; i++) {
item = &table[i];
parent = clk_get_parent_by_index(clk, item->parent_index);
parent_rate = __clk_get_rate(parent);
if (parent_rate % item->rate) {
item->valid = 0;
} else {
item->divisor = parent_rate / item->rate;
item->valid = 1;
}
}
}
static int _set_rate(struct mmp_clk_mix *mix, u32 mux_val, u32 div_val,
unsigned int change_mux, unsigned int change_div)
{
struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
u8 width, shift;
u32 mux_div, fc_req;
int ret, timeout = 50;
unsigned long flags = 0;
if (!change_mux && !change_div)
return -EINVAL;
if (mix->lock)
spin_lock_irqsave(mix->lock, flags);
if (mix->type == MMP_CLK_MIX_TYPE_V1
|| mix->type == MMP_CLK_MIX_TYPE_V2)
mux_div = readl(ri->reg_clk_ctrl);
else
mux_div = readl(ri->reg_clk_sel);
if (change_div) {
width = ri->width_div;
shift = ri->shift_div;
mux_div &= ~MMP_CLK_BITS_MASK(width, shift);
mux_div |= MMP_CLK_BITS_SET_VAL(div_val, width, shift);
}
if (change_mux) {
width = ri->width_mux;
shift = ri->shift_mux;
mux_div &= ~MMP_CLK_BITS_MASK(width, shift);
mux_div |= MMP_CLK_BITS_SET_VAL(mux_val, width, shift);
}
if (mix->type == MMP_CLK_MIX_TYPE_V1) {
writel(mux_div, ri->reg_clk_ctrl);
} else if (mix->type == MMP_CLK_MIX_TYPE_V2) {
mux_div |= (1 << ri->bit_fc);
writel(mux_div, ri->reg_clk_ctrl);
do {
fc_req = readl(ri->reg_clk_ctrl);
timeout--;
if (!(fc_req & (1 << ri->bit_fc)))
break;
} while (timeout);
if (timeout == 0) {
pr_err("%s:%s cannot do frequency change\n",
__func__, __clk_get_name(mix->hw.clk));
ret = -EBUSY;
goto error;
}
} else {
fc_req = readl(ri->reg_clk_ctrl);
fc_req |= 1 << ri->bit_fc;
writel(fc_req, ri->reg_clk_ctrl);
writel(mux_div, ri->reg_clk_sel);
fc_req &= ~(1 << ri->bit_fc);
}
ret = 0;
error:
if (mix->lock)
spin_unlock_irqrestore(mix->lock, flags);
return ret;
}
static long mmp_clk_mix_determine_rate(struct clk_hw *hw, unsigned long rate,
unsigned long min_rate,
unsigned long max_rate,
unsigned long *best_parent_rate,
struct clk_hw **best_parent_clk)
{
struct mmp_clk_mix *mix = to_clk_mix(hw);
struct mmp_clk_mix_clk_table *item;
struct clk *parent, *parent_best, *mix_clk;
unsigned long parent_rate, mix_rate, mix_rate_best, parent_rate_best;
unsigned long gap, gap_best;
u32 div_val_max;
unsigned int div;
int i, j;
mix_clk = hw->clk;
parent = NULL;
mix_rate_best = 0;
parent_rate_best = 0;
gap_best = rate;
parent_best = NULL;
if (mix->table) {
for (i = 0; i < mix->table_size; i++) {
item = &mix->table[i];
if (item->valid == 0)
continue;
parent = clk_get_parent_by_index(mix_clk,
item->parent_index);
parent_rate = __clk_get_rate(parent);
mix_rate = parent_rate / item->divisor;
gap = abs(mix_rate - rate);
if (parent_best == NULL || gap < gap_best) {
parent_best = parent;
parent_rate_best = parent_rate;
mix_rate_best = mix_rate;
gap_best = gap;
if (gap_best == 0)
goto found;
}
}
} else {
for (i = 0; i < __clk_get_num_parents(mix_clk); i++) {
parent = clk_get_parent_by_index(mix_clk, i);
parent_rate = __clk_get_rate(parent);
div_val_max = _get_maxdiv(mix);
for (j = 0; j < div_val_max; j++) {
div = _get_div(mix, j);
mix_rate = parent_rate / div;
gap = abs(mix_rate - rate);
if (parent_best == NULL || gap < gap_best) {
parent_best = parent;
parent_rate_best = parent_rate;
mix_rate_best = mix_rate;
gap_best = gap;
if (gap_best == 0)
goto found;
}
}
}
}
found:
*best_parent_rate = parent_rate_best;
*best_parent_clk = __clk_get_hw(parent_best);
return mix_rate_best;
}
static int mmp_clk_mix_set_rate_and_parent(struct clk_hw *hw,
unsigned long rate,
unsigned long parent_rate,
u8 index)
{
struct mmp_clk_mix *mix = to_clk_mix(hw);
unsigned int div;
u32 div_val, mux_val;
div = parent_rate / rate;
div_val = _get_div_val(mix, div);
mux_val = _get_mux_val(mix, index);
return _set_rate(mix, mux_val, div_val, 1, 1);
}
static u8 mmp_clk_mix_get_parent(struct clk_hw *hw)
{
struct mmp_clk_mix *mix = to_clk_mix(hw);
struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
unsigned long flags = 0;
u32 mux_div = 0;
u8 width, shift;
u32 mux_val;
if (mix->lock)
spin_lock_irqsave(mix->lock, flags);
if (mix->type == MMP_CLK_MIX_TYPE_V1
|| mix->type == MMP_CLK_MIX_TYPE_V2)
mux_div = readl(ri->reg_clk_ctrl);
else
mux_div = readl(ri->reg_clk_sel);
if (mix->lock)
spin_unlock_irqrestore(mix->lock, flags);
width = mix->reg_info.width_mux;
shift = mix->reg_info.shift_mux;
mux_val = MMP_CLK_BITS_GET_VAL(mux_div, width, shift);
return _get_mux(mix, mux_val);
}
static unsigned long mmp_clk_mix_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct mmp_clk_mix *mix = to_clk_mix(hw);
struct mmp_clk_mix_reg_info *ri = &mix->reg_info;
unsigned long flags = 0;
u32 mux_div = 0;
u8 width, shift;
unsigned int div;
if (mix->lock)
spin_lock_irqsave(mix->lock, flags);
if (mix->type == MMP_CLK_MIX_TYPE_V1
|| mix->type == MMP_CLK_MIX_TYPE_V2)
mux_div = readl(ri->reg_clk_ctrl);
else
mux_div = readl(ri->reg_clk_sel);
if (mix->lock)
spin_unlock_irqrestore(mix->lock, flags);
width = mix->reg_info.width_div;
shift = mix->reg_info.shift_div;
div = _get_div(mix, MMP_CLK_BITS_GET_VAL(mux_div, width, shift));
return parent_rate / div;
}
static int mmp_clk_set_parent(struct clk_hw *hw, u8 index)
{
struct mmp_clk_mix *mix = to_clk_mix(hw);
struct mmp_clk_mix_clk_table *item;
int i;
u32 div_val, mux_val;
if (mix->table) {
for (i = 0; i < mix->table_size; i++) {
item = &mix->table[i];
if (item->valid == 0)
continue;
if (item->parent_index == index)
break;
}
if (i < mix->table_size) {
div_val = _get_div_val(mix, item->divisor);
mux_val = _get_mux_val(mix, item->parent_index);
} else
return -EINVAL;
} else {
mux_val = _get_mux_val(mix, index);
div_val = 0;
}
return _set_rate(mix, mux_val, div_val, 1, div_val ? 1 : 0);
}
static int mmp_clk_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long best_parent_rate)
{
struct mmp_clk_mix *mix = to_clk_mix(hw);
struct mmp_clk_mix_clk_table *item;
unsigned long parent_rate;
unsigned int best_divisor;
struct clk *mix_clk, *parent;
int i;
best_divisor = best_parent_rate / rate;
mix_clk = hw->clk;
if (mix->table) {
for (i = 0; i < mix->table_size; i++) {
item = &mix->table[i];
if (item->valid == 0)
continue;
parent = clk_get_parent_by_index(mix_clk,
item->parent_index);
parent_rate = __clk_get_rate(parent);
if (parent_rate == best_parent_rate
&& item->divisor == best_divisor)
break;
}
if (i < mix->table_size)
return _set_rate(mix,
_get_mux_val(mix, item->parent_index),
_get_div_val(mix, item->divisor),
1, 1);
else
return -EINVAL;
} else {
for (i = 0; i < __clk_get_num_parents(mix_clk); i++) {
parent = clk_get_parent_by_index(mix_clk, i);
parent_rate = __clk_get_rate(parent);
if (parent_rate == best_parent_rate)
break;
}
if (i < __clk_get_num_parents(mix_clk))
return _set_rate(mix, _get_mux_val(mix, i),
_get_div_val(mix, best_divisor), 1, 1);
else
return -EINVAL;
}
}
static void mmp_clk_mix_init(struct clk_hw *hw)
{
struct mmp_clk_mix *mix = to_clk_mix(hw);
if (mix->table)
_filter_clk_table(mix, mix->table, mix->table_size);
}
const struct clk_ops mmp_clk_mix_ops = {
.determine_rate = mmp_clk_mix_determine_rate,
.set_rate_and_parent = mmp_clk_mix_set_rate_and_parent,
.set_rate = mmp_clk_set_rate,
.set_parent = mmp_clk_set_parent,
.get_parent = mmp_clk_mix_get_parent,
.recalc_rate = mmp_clk_mix_recalc_rate,
.init = mmp_clk_mix_init,
};
struct clk *mmp_clk_register_mix(struct device *dev,
const char *name,
const char **parent_names,
u8 num_parents,
unsigned long flags,
struct mmp_clk_mix_config *config,
spinlock_t *lock)
{
struct mmp_clk_mix *mix;
struct clk *clk;
struct clk_init_data init;
size_t table_bytes;
mix = kzalloc(sizeof(*mix), GFP_KERNEL);
if (!mix) {
pr_err("%s:%s: could not allocate mmp mix clk\n",
__func__, name);
return ERR_PTR(-ENOMEM);
}
init.name = name;
init.flags = flags | CLK_GET_RATE_NOCACHE;
init.parent_names = parent_names;
init.num_parents = num_parents;
init.ops = &mmp_clk_mix_ops;
memcpy(&mix->reg_info, &config->reg_info, sizeof(config->reg_info));
if (config->table) {
table_bytes = sizeof(*config->table) * config->table_size;
mix->table = kzalloc(table_bytes, GFP_KERNEL);
if (!mix->table) {
pr_err("%s:%s: could not allocate mmp mix table\n",
__func__, name);
kfree(mix);
return ERR_PTR(-ENOMEM);
}
memcpy(mix->table, config->table, table_bytes);
mix->table_size = config->table_size;
}
if (config->mux_table) {
table_bytes = sizeof(u32) * num_parents;
mix->mux_table = kzalloc(table_bytes, GFP_KERNEL);
if (!mix->mux_table) {
pr_err("%s:%s: could not allocate mmp mix mux-table\n",
__func__, name);
kfree(mix->table);
kfree(mix);
return ERR_PTR(-ENOMEM);
}
memcpy(mix->mux_table, config->mux_table, table_bytes);
}
mix->div_flags = config->div_flags;
mix->mux_flags = config->mux_flags;
mix->lock = lock;
mix->hw.init = &init;
if (config->reg_info.bit_fc >= 32)
mix->type = MMP_CLK_MIX_TYPE_V1;
else if (config->reg_info.reg_clk_sel)
mix->type = MMP_CLK_MIX_TYPE_V3;
else
mix->type = MMP_CLK_MIX_TYPE_V2;
clk = clk_register(dev, &mix->hw);
if (IS_ERR(clk)) {
kfree(mix->mux_table);
kfree(mix->table);
kfree(mix);
}
return clk;
}