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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2019 DENX Software Engineering
* Lukasz Majewski, DENX Software Engineering, lukma@denx.de
*
* Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
* Copyright (C) 2011 Richard Zhao, Linaro <richard.zhao@linaro.org>
* Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
*
*/
#include <common.h>
#include <asm/io.h>
#include <malloc.h>
#include <clk-uclass.h>
#include <dm/device.h>
#include <dm/devres.h>
#include <dm/uclass.h>
#include <dm/lists.h>
#include <dm/device-internal.h>
#include <linux/bug.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/log2.h>
#include <div64.h>
#include <clk.h>
#include "clk.h"
#define UBOOT_DM_CLK_CCF_DIVIDER "ccf_clk_divider"
static unsigned int _get_table_div(const struct clk_div_table *table,
unsigned int val)
{
const struct clk_div_table *clkt;
for (clkt = table; clkt->div; clkt++)
if (clkt->val == val)
return clkt->div;
return 0;
}
static unsigned int _get_div(const struct clk_div_table *table,
unsigned int val, unsigned long flags, u8 width)
{
if (flags & CLK_DIVIDER_ONE_BASED)
return val;
if (flags & CLK_DIVIDER_POWER_OF_TWO)
return 1 << val;
if (flags & CLK_DIVIDER_MAX_AT_ZERO)
return val ? val : clk_div_mask(width) + 1;
if (table)
return _get_table_div(table, val);
return val + 1;
}
unsigned long divider_recalc_rate(struct clk *hw, unsigned long parent_rate,
unsigned int val,
const struct clk_div_table *table,
unsigned long flags, unsigned long width)
{
unsigned int div;
div = _get_div(table, val, flags, width);
if (!div) {
WARN(!(flags & CLK_DIVIDER_ALLOW_ZERO),
"%s: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n",
clk_hw_get_name(hw));
return parent_rate;
}
return DIV_ROUND_UP_ULL((u64)parent_rate, div);
}
static ulong clk_divider_recalc_rate(struct clk *clk)
{
struct clk_divider *divider = to_clk_divider(clk);
unsigned long parent_rate = clk_get_parent_rate(clk);
unsigned int val;
#if CONFIG_IS_ENABLED(SANDBOX_CLK_CCF)
val = divider->io_divider_val;
#else
val = readl(divider->reg);
#endif
val >>= divider->shift;
val &= clk_div_mask(divider->width);
return divider_recalc_rate(clk, parent_rate, val, divider->table,
divider->flags, divider->width);
}
static bool _is_valid_table_div(const struct clk_div_table *table,
unsigned int div)
{
const struct clk_div_table *clkt;
for (clkt = table; clkt->div; clkt++)
if (clkt->div == div)
return true;
return false;
}
static bool _is_valid_div(const struct clk_div_table *table, unsigned int div,
unsigned long flags)
{
if (flags & CLK_DIVIDER_POWER_OF_TWO)
return is_power_of_2(div);
if (table)
return _is_valid_table_div(table, div);
return true;
}
static unsigned int _get_table_val(const struct clk_div_table *table,
unsigned int div)
{
const struct clk_div_table *clkt;
for (clkt = table; clkt->div; clkt++)
if (clkt->div == div)
return clkt->val;
return 0;
}
static unsigned int _get_val(const struct clk_div_table *table,
unsigned int div, unsigned long flags, u8 width)
{
if (flags & CLK_DIVIDER_ONE_BASED)
return div;
if (flags & CLK_DIVIDER_POWER_OF_TWO)
return __ffs(div);
if (flags & CLK_DIVIDER_MAX_AT_ZERO)
return (div == clk_div_mask(width) + 1) ? 0 : div;
if (table)
return _get_table_val(table, div);
return div - 1;
}
int divider_get_val(unsigned long rate, unsigned long parent_rate,
const struct clk_div_table *table, u8 width,
unsigned long flags)
{
unsigned int div, value;
div = DIV_ROUND_UP_ULL((u64)parent_rate, rate);
if (!_is_valid_div(table, div, flags))
return -EINVAL;
value = _get_val(table, div, flags, width);
return min_t(unsigned int, value, clk_div_mask(width));
}
static ulong clk_divider_set_rate(struct clk *clk, unsigned long rate)
{
struct clk_divider *divider = to_clk_divider(clk);
unsigned long parent_rate = clk_get_parent_rate(clk);
int value;
u32 val;
value = divider_get_val(rate, parent_rate, divider->table,
divider->width, divider->flags);
if (value < 0)
return value;
if (divider->flags & CLK_DIVIDER_HIWORD_MASK) {
val = clk_div_mask(divider->width) << (divider->shift + 16);
} else {
val = readl(divider->reg);
val &= ~(clk_div_mask(divider->width) << divider->shift);
}
val |= (u32)value << divider->shift;
writel(val, divider->reg);
return clk_get_rate(clk);
}
const struct clk_ops clk_divider_ops = {
.get_rate = clk_divider_recalc_rate,
.set_rate = clk_divider_set_rate,
};
static struct clk *_register_divider(struct device *dev, const char *name,
const char *parent_name, unsigned long flags,
void __iomem *reg, u8 shift, u8 width,
u8 clk_divider_flags, const struct clk_div_table *table)
{
struct clk_divider *div;
struct clk *clk;
int ret;
if (clk_divider_flags & CLK_DIVIDER_HIWORD_MASK) {
if (width + shift > 16) {
pr_warn("divider value exceeds LOWORD field\n");
return ERR_PTR(-EINVAL);
}
}
/* allocate the divider */
div = kzalloc(sizeof(*div), GFP_KERNEL);
if (!div)
return ERR_PTR(-ENOMEM);
/* struct clk_divider assignments */
div->reg = reg;
div->shift = shift;
div->width = width;
div->flags = clk_divider_flags;
div->table = table;
#if CONFIG_IS_ENABLED(SANDBOX_CLK_CCF)
div->io_divider_val = *(u32 *)reg;
#endif
/* register the clock */
clk = &div->clk;
clk->flags = flags;
ret = clk_register(clk, UBOOT_DM_CLK_CCF_DIVIDER, name, parent_name);
if (ret) {
kfree(div);
return ERR_PTR(ret);
}
return clk;
}
struct clk *clk_register_divider(struct device *dev, const char *name,
const char *parent_name, unsigned long flags,
void __iomem *reg, u8 shift, u8 width,
u8 clk_divider_flags)
{
struct clk *clk;
clk = _register_divider(dev, name, parent_name, flags, reg, shift,
width, clk_divider_flags, NULL);
if (IS_ERR(clk))
return ERR_CAST(clk);
return clk;
}
U_BOOT_DRIVER(ccf_clk_divider) = {
.name = UBOOT_DM_CLK_CCF_DIVIDER,
.id = UCLASS_CLK,
.ops = &clk_divider_ops,
.flags = DM_FLAG_PRE_RELOC,
};