// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2016 Maxime Ripard
* Maxime Ripard <[email protected]>
*/
#include <linux/clk-provider.h>
#include <linux/io.h>
#include "ccu_gate.h"
#include "ccu_nkm.h"
struct _ccu_nkm {
unsigned long n, min_n, max_n;
unsigned long k, min_k, max_k;
unsigned long m, min_m, max_m;
};
static bool ccu_nkm_is_valid_rate(struct ccu_common *common, unsigned long parent,
unsigned long n, unsigned long m)
{
struct ccu_nkm *nkm = container_of(common, struct ccu_nkm, common);
if (nkm->max_m_n_ratio && (m > nkm->max_m_n_ratio * n))
return false;
if (nkm->min_parent_m_ratio && (parent < nkm->min_parent_m_ratio * m))
return false;
return true;
}
static unsigned long ccu_nkm_find_best_with_parent_adj(struct ccu_common *common,
struct clk_hw *parent_hw,
unsigned long *parent, unsigned long rate,
struct _ccu_nkm *nkm)
{
unsigned long best_rate = 0, best_parent_rate = *parent;
unsigned long best_n = 0, best_k = 0, best_m = 0;
unsigned long _n, _k, _m;
for (_k = nkm->min_k; _k <= nkm->max_k; _k++) {
for (_n = nkm->min_n; _n <= nkm->max_n; _n++) {
for (_m = nkm->min_m; _m <= nkm->max_m; _m++) {
unsigned long tmp_rate, tmp_parent;
tmp_parent = clk_hw_round_rate(parent_hw, rate * _m / (_n * _k));
if (!ccu_nkm_is_valid_rate(common, tmp_parent, _n, _m))
continue;
tmp_rate = tmp_parent * _n * _k / _m;
if (ccu_is_better_rate(common, rate, tmp_rate, best_rate) ||
(tmp_parent == *parent && tmp_rate == best_rate)) {
best_rate = tmp_rate;
best_parent_rate = tmp_parent;
best_n = _n;
best_k = _k;
best_m = _m;
}
}
}
}
nkm->n = best_n;
nkm->k = best_k;
nkm->m = best_m;
*parent = best_parent_rate;
return best_rate;
}
static unsigned long ccu_nkm_find_best(unsigned long parent, unsigned long rate,
struct _ccu_nkm *nkm, struct ccu_common *common)
{
unsigned long best_rate = 0;
unsigned long best_n = 0, best_k = 0, best_m = 0;
unsigned long _n, _k, _m;
for (_k = nkm->min_k; _k <= nkm->max_k; _k++) {
for (_n = nkm->min_n; _n <= nkm->max_n; _n++) {
for (_m = nkm->min_m; _m <= nkm->max_m; _m++) {
if (!ccu_nkm_is_valid_rate(common, parent, _n, _m))
continue;
unsigned long tmp_rate;
tmp_rate = parent * _n * _k / _m;
if (ccu_is_better_rate(common, rate, tmp_rate, best_rate)) {
best_rate = tmp_rate;
best_n = _n;
best_k = _k;
best_m = _m;
}
}
}
}
nkm->n = best_n;
nkm->k = best_k;
nkm->m = best_m;
return best_rate;
}
static void ccu_nkm_disable(struct clk_hw *hw)
{
struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
return ccu_gate_helper_disable(&nkm->common, nkm->enable);
}
static int ccu_nkm_enable(struct clk_hw *hw)
{
struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
return ccu_gate_helper_enable(&nkm->common, nkm->enable);
}
static int ccu_nkm_is_enabled(struct clk_hw *hw)
{
struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
return ccu_gate_helper_is_enabled(&nkm->common, nkm->enable);
}
static unsigned long ccu_nkm_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
unsigned long n, m, k, rate;
u32 reg;
reg = readl(nkm->common.base + nkm->common.reg);
n = reg >> nkm->n.shift;
n &= (1 << nkm->n.width) - 1;
n += nkm->n.offset;
if (!n)
n++;
k = reg >> nkm->k.shift;
k &= (1 << nkm->k.width) - 1;
k += nkm->k.offset;
if (!k)
k++;
m = reg >> nkm->m.shift;
m &= (1 << nkm->m.width) - 1;
m += nkm->m.offset;
if (!m)
m++;
rate = parent_rate * n * k / m;
if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
rate /= nkm->fixed_post_div;
return rate;
}
static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux,
struct clk_hw *parent_hw,
unsigned long *parent_rate,
unsigned long rate,
void *data)
{
struct ccu_nkm *nkm = data;
struct _ccu_nkm _nkm;
_nkm.min_n = nkm->n.min ?: 1;
_nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
_nkm.min_k = nkm->k.min ?: 1;
_nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
_nkm.min_m = 1;
_nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
rate *= nkm->fixed_post_div;
if (!clk_hw_can_set_rate_parent(&nkm->common.hw))
rate = ccu_nkm_find_best(*parent_rate, rate, &_nkm, &nkm->common);
else
rate = ccu_nkm_find_best_with_parent_adj(&nkm->common, parent_hw, parent_rate, rate,
&_nkm);
if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
rate /= nkm->fixed_post_div;
return rate;
}
static int ccu_nkm_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
return ccu_mux_helper_determine_rate(&nkm->common, &nkm->mux,
req, ccu_nkm_round_rate, nkm);
}
static int ccu_nkm_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
struct _ccu_nkm _nkm;
unsigned long flags;
u32 reg;
if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
rate *= nkm->fixed_post_div;
_nkm.min_n = nkm->n.min ?: 1;
_nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
_nkm.min_k = nkm->k.min ?: 1;
_nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
_nkm.min_m = 1;
_nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
ccu_nkm_find_best(parent_rate, rate, &_nkm, &nkm->common);
spin_lock_irqsave(nkm->common.lock, flags);
reg = readl(nkm->common.base + nkm->common.reg);
reg &= ~GENMASK(nkm->n.width + nkm->n.shift - 1, nkm->n.shift);
reg &= ~GENMASK(nkm->k.width + nkm->k.shift - 1, nkm->k.shift);
reg &= ~GENMASK(nkm->m.width + nkm->m.shift - 1, nkm->m.shift);
reg |= (_nkm.n - nkm->n.offset) << nkm->n.shift;
reg |= (_nkm.k - nkm->k.offset) << nkm->k.shift;
reg |= (_nkm.m - nkm->m.offset) << nkm->m.shift;
writel(reg, nkm->common.base + nkm->common.reg);
spin_unlock_irqrestore(nkm->common.lock, flags);
ccu_helper_wait_for_lock(&nkm->common, nkm->lock);
return 0;
}
static u8 ccu_nkm_get_parent(struct clk_hw *hw)
{
struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
return ccu_mux_helper_get_parent(&nkm->common, &nkm->mux);
}
static int ccu_nkm_set_parent(struct clk_hw *hw, u8 index)
{
struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
return ccu_mux_helper_set_parent(&nkm->common, &nkm->mux, index);
}
const struct clk_ops ccu_nkm_ops = {
.disable = ccu_nkm_disable,
.enable = ccu_nkm_enable,
.is_enabled = ccu_nkm_is_enabled,
.get_parent = ccu_nkm_get_parent,
.set_parent = ccu_nkm_set_parent,
.determine_rate = ccu_nkm_determine_rate,
.recalc_rate = ccu_nkm_recalc_rate,
.set_rate = ccu_nkm_set_rate,
};
EXPORT_SYMBOL_NS_GPL(ccu_nkm_ops, SUNXI_CCU);
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