linux/drivers/clk/sunxi-ng/ccu_mult.c
Maxime Ripard aa15233517 clk: sunxi-ng: Add N-class clocks support
Add support for the class with a single factor, N, being a multiplier.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
2016-09-10 11:41:19 +02:00

134 lines
3.2 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_mult.h"
static void ccu_mult_find_best(unsigned long parent, unsigned long rate,
unsigned int max_n, unsigned int *n)
{
*n = rate / parent;
}
static unsigned long ccu_mult_round_rate(struct ccu_mux_internal *mux,
unsigned long parent_rate,
unsigned long rate,
void *data)
{
struct ccu_mult *cm = data;
unsigned int n;
ccu_mult_find_best(parent_rate, rate, 1 << cm->mult.width, &n);
return parent_rate * n;
}
static void ccu_mult_disable(struct clk_hw *hw)
{
struct ccu_mult *cm = hw_to_ccu_mult(hw);
return ccu_gate_helper_disable(&cm->common, cm->enable);
}
static int ccu_mult_enable(struct clk_hw *hw)
{
struct ccu_mult *cm = hw_to_ccu_mult(hw);
return ccu_gate_helper_enable(&cm->common, cm->enable);
}
static int ccu_mult_is_enabled(struct clk_hw *hw)
{
struct ccu_mult *cm = hw_to_ccu_mult(hw);
return ccu_gate_helper_is_enabled(&cm->common, cm->enable);
}
static unsigned long ccu_mult_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct ccu_mult *cm = hw_to_ccu_mult(hw);
unsigned long val;
u32 reg;
reg = readl(cm->common.base + cm->common.reg);
val = reg >> cm->mult.shift;
val &= (1 << cm->mult.width) - 1;
ccu_mux_helper_adjust_parent_for_prediv(&cm->common, &cm->mux, -1,
&parent_rate);
return parent_rate * (val + 1);
}
static int ccu_mult_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct ccu_mult *cm = hw_to_ccu_mult(hw);
return ccu_mux_helper_determine_rate(&cm->common, &cm->mux,
req, ccu_mult_round_rate, cm);
}
static int ccu_mult_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct ccu_mult *cm = hw_to_ccu_mult(hw);
unsigned long flags;
unsigned int n;
u32 reg;
ccu_mux_helper_adjust_parent_for_prediv(&cm->common, &cm->mux, -1,
&parent_rate);
ccu_mult_find_best(parent_rate, rate, 1 << cm->mult.width, &n);
spin_lock_irqsave(cm->common.lock, flags);
reg = readl(cm->common.base + cm->common.reg);
reg &= ~GENMASK(cm->mult.width + cm->mult.shift - 1, cm->mult.shift);
writel(reg | ((n - 1) << cm->mult.shift),
cm->common.base + cm->common.reg);
spin_unlock_irqrestore(cm->common.lock, flags);
return 0;
}
static u8 ccu_mult_get_parent(struct clk_hw *hw)
{
struct ccu_mult *cm = hw_to_ccu_mult(hw);
return ccu_mux_helper_get_parent(&cm->common, &cm->mux);
}
static int ccu_mult_set_parent(struct clk_hw *hw, u8 index)
{
struct ccu_mult *cm = hw_to_ccu_mult(hw);
return ccu_mux_helper_set_parent(&cm->common, &cm->mux, index);
}
const struct clk_ops ccu_mult_ops = {
.disable = ccu_mult_disable,
.enable = ccu_mult_enable,
.is_enabled = ccu_mult_is_enabled,
.get_parent = ccu_mult_get_parent,
.set_parent = ccu_mult_set_parent,
.determine_rate = ccu_mult_determine_rate,
.recalc_rate = ccu_mult_recalc_rate,
.set_rate = ccu_mult_set_rate,
};