linux/drivers/clk/sunxi-ng/ccu_div.c
Maxime Ripard bf3be2caa5 clk: sunxi-ng: Call divider_round_rate if we only have a single parent
The divider_get_val function that is used in our determine_rate callback
doesn't try to change the parent rate at all, while clk_divider_bestdiv,
used in divider_round_rate, does.

If we have a single parent, call divider_round_rate.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
2017-01-27 11:05:34 +01:00

149 lines
3.7 KiB
C

/*
* 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 "ccu_gate.h"
#include "ccu_div.h"
static unsigned long ccu_div_round_rate(struct ccu_mux_internal *mux,
unsigned long parent_rate,
unsigned long rate,
void *data)
{
struct ccu_div *cd = data;
unsigned long val;
/*
* We can't use divider_round_rate that assumes that there's
* several parents, while we might be called to evaluate
* several different parents.
*/
val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
cd->div.flags);
return divider_recalc_rate(&cd->common.hw, parent_rate, val,
cd->div.table, cd->div.flags);
}
static void ccu_div_disable(struct clk_hw *hw)
{
struct ccu_div *cd = hw_to_ccu_div(hw);
return ccu_gate_helper_disable(&cd->common, cd->enable);
}
static int ccu_div_enable(struct clk_hw *hw)
{
struct ccu_div *cd = hw_to_ccu_div(hw);
return ccu_gate_helper_enable(&cd->common, cd->enable);
}
static int ccu_div_is_enabled(struct clk_hw *hw)
{
struct ccu_div *cd = hw_to_ccu_div(hw);
return ccu_gate_helper_is_enabled(&cd->common, cd->enable);
}
static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct ccu_div *cd = hw_to_ccu_div(hw);
unsigned long val;
u32 reg;
reg = readl(cd->common.base + cd->common.reg);
val = reg >> cd->div.shift;
val &= (1 << cd->div.width) - 1;
ccu_mux_helper_adjust_parent_for_prediv(&cd->common, &cd->mux, -1,
&parent_rate);
return divider_recalc_rate(hw, parent_rate, val, cd->div.table,
cd->div.flags);
}
static int ccu_div_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct ccu_div *cd = hw_to_ccu_div(hw);
if (clk_hw_get_num_parents(hw) == 1) {
req->rate = divider_round_rate(hw, req->rate,
&req->best_parent_rate,
cd->div.table,
cd->div.width,
cd->div.flags);
req->best_parent_hw = clk_hw_get_parent(hw);
return 0;
}
return ccu_mux_helper_determine_rate(&cd->common, &cd->mux,
req, ccu_div_round_rate, cd);
}
static int ccu_div_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct ccu_div *cd = hw_to_ccu_div(hw);
unsigned long flags;
unsigned long val;
u32 reg;
ccu_mux_helper_adjust_parent_for_prediv(&cd->common, &cd->mux, -1,
&parent_rate);
val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
cd->div.flags);
spin_lock_irqsave(cd->common.lock, flags);
reg = readl(cd->common.base + cd->common.reg);
reg &= ~GENMASK(cd->div.width + cd->div.shift - 1, cd->div.shift);
writel(reg | (val << cd->div.shift),
cd->common.base + cd->common.reg);
spin_unlock_irqrestore(cd->common.lock, flags);
return 0;
}
static u8 ccu_div_get_parent(struct clk_hw *hw)
{
struct ccu_div *cd = hw_to_ccu_div(hw);
return ccu_mux_helper_get_parent(&cd->common, &cd->mux);
}
static int ccu_div_set_parent(struct clk_hw *hw, u8 index)
{
struct ccu_div *cd = hw_to_ccu_div(hw);
return ccu_mux_helper_set_parent(&cd->common, &cd->mux, index);
}
const struct clk_ops ccu_div_ops = {
.disable = ccu_div_disable,
.enable = ccu_div_enable,
.is_enabled = ccu_div_is_enabled,
.get_parent = ccu_div_get_parent,
.set_parent = ccu_div_set_parent,
.determine_rate = ccu_div_determine_rate,
.recalc_rate = ccu_div_recalc_rate,
.set_rate = ccu_div_set_rate,
};