[mirror_ubuntu-hirsute-kernel.git] / drivers / clk / sunxi-ng / ccu_nkmp.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 <linux/io.h>

#include "ccu_gate.h"
#include "ccu_nkmp.h"

struct _ccu_nkmp {
	unsigned long	n, min_n, max_n;
	unsigned long	k, min_k, max_k;
	unsigned long	m, min_m, max_m;
	unsigned long	p, min_p, max_p;
};

static unsigned long ccu_nkmp_calc_rate(unsigned long parent,
					unsigned long n, unsigned long k,
					unsigned long m, unsigned long p)
{
	u64 rate = parent;

	rate *= n * k;
	do_div(rate, m * p);

	return rate;
}

static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate,
			       struct _ccu_nkmp *nkmp)
{
	unsigned long best_rate = 0;
	unsigned long best_n = 0, best_k = 0, best_m = 0, best_p = 0;
	unsigned long _n, _k, _m, _p;

	for (_k = nkmp->min_k; _k <= nkmp->max_k; _k++) {
		for (_n = nkmp->min_n; _n <= nkmp->max_n; _n++) {
			for (_m = nkmp->min_m; _m <= nkmp->max_m; _m++) {
				for (_p = nkmp->min_p; _p <= nkmp->max_p; _p <<= 1) {
					unsigned long tmp_rate;

					tmp_rate = ccu_nkmp_calc_rate(parent,
								      _n, _k,
								      _m, _p);

					if (tmp_rate > rate)
						continue;

					if ((rate - tmp_rate) < (rate - best_rate)) {
						best_rate = tmp_rate;
						best_n = _n;
						best_k = _k;
						best_m = _m;
						best_p = _p;
					}
				}
			}
		}
	}

	nkmp->n = best_n;
	nkmp->k = best_k;
	nkmp->m = best_m;
	nkmp->p = best_p;
}

static void ccu_nkmp_disable(struct clk_hw *hw)
{
	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);

	return ccu_gate_helper_disable(&nkmp->common, nkmp->enable);
}

static int ccu_nkmp_enable(struct clk_hw *hw)
{
	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);

	return ccu_gate_helper_enable(&nkmp->common, nkmp->enable);
}

static int ccu_nkmp_is_enabled(struct clk_hw *hw)
{
	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);

	return ccu_gate_helper_is_enabled(&nkmp->common, nkmp->enable);
}

static unsigned long ccu_nkmp_recalc_rate(struct clk_hw *hw,
					unsigned long parent_rate)
{
	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
	unsigned long n, m, k, p, rate;
	u32 reg;

	reg = readl(nkmp->common.base + nkmp->common.reg);

	n = reg >> nkmp->n.shift;
	n &= (1 << nkmp->n.width) - 1;
	n += nkmp->n.offset;
	if (!n)
		n++;

	k = reg >> nkmp->k.shift;
	k &= (1 << nkmp->k.width) - 1;
	k += nkmp->k.offset;
	if (!k)
		k++;

	m = reg >> nkmp->m.shift;
	m &= (1 << nkmp->m.width) - 1;
	m += nkmp->m.offset;
	if (!m)
		m++;

	p = reg >> nkmp->p.shift;
	p &= (1 << nkmp->p.width) - 1;

	rate = ccu_nkmp_calc_rate(parent_rate, n, k, m, 1 << p);
	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
		rate /= nkmp->fixed_post_div;

	return rate;
}

static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate,
			      unsigned long *parent_rate)
{
	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
	struct _ccu_nkmp _nkmp;

	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
		rate *= nkmp->fixed_post_div;

	if (nkmp->max_rate && rate > nkmp->max_rate) {
		rate = nkmp->max_rate;
		if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
			rate /= nkmp->fixed_post_div;
		return rate;
	}

	_nkmp.min_n = nkmp->n.min ?: 1;
	_nkmp.max_n = nkmp->n.max ?: 1 << nkmp->n.width;
	_nkmp.min_k = nkmp->k.min ?: 1;
	_nkmp.max_k = nkmp->k.max ?: 1 << nkmp->k.width;
	_nkmp.min_m = 1;
	_nkmp.max_m = nkmp->m.max ?: 1 << nkmp->m.width;
	_nkmp.min_p = 1;
	_nkmp.max_p = nkmp->p.max ?: 1 << ((1 << nkmp->p.width) - 1);

	ccu_nkmp_find_best(*parent_rate, rate, &_nkmp);

	rate = ccu_nkmp_calc_rate(*parent_rate, _nkmp.n, _nkmp.k,
				  _nkmp.m, _nkmp.p);
	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
		rate = rate / nkmp->fixed_post_div;

	return rate;
}

static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate,
			   unsigned long parent_rate)
{
	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
	u32 n_mask = 0, k_mask = 0, m_mask = 0, p_mask = 0;
	struct _ccu_nkmp _nkmp;
	unsigned long flags;
	u32 reg;

	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
		rate = rate * nkmp->fixed_post_div;

	_nkmp.min_n = nkmp->n.min ?: 1;
	_nkmp.max_n = nkmp->n.max ?: 1 << nkmp->n.width;
	_nkmp.min_k = nkmp->k.min ?: 1;
	_nkmp.max_k = nkmp->k.max ?: 1 << nkmp->k.width;
	_nkmp.min_m = 1;
	_nkmp.max_m = nkmp->m.max ?: 1 << nkmp->m.width;
	_nkmp.min_p = 1;
	_nkmp.max_p = nkmp->p.max ?: 1 << ((1 << nkmp->p.width) - 1);

	ccu_nkmp_find_best(parent_rate, rate, &_nkmp);

	/*
	 * If width is 0, GENMASK() macro may not generate expected mask (0)
	 * as it falls under undefined behaviour by C standard due to shifts
	 * which are equal or greater than width of left operand. This can
	 * be easily avoided by explicitly checking if width is 0.
	 */
	if (nkmp->n.width)
		n_mask = GENMASK(nkmp->n.width + nkmp->n.shift - 1,
				 nkmp->n.shift);
	if (nkmp->k.width)
		k_mask = GENMASK(nkmp->k.width + nkmp->k.shift - 1,
				 nkmp->k.shift);
	if (nkmp->m.width)
		m_mask = GENMASK(nkmp->m.width + nkmp->m.shift - 1,
				 nkmp->m.shift);
	if (nkmp->p.width)
		p_mask = GENMASK(nkmp->p.width + nkmp->p.shift - 1,
				 nkmp->p.shift);

	spin_lock_irqsave(nkmp->common.lock, flags);

	reg = readl(nkmp->common.base + nkmp->common.reg);
	reg &= ~(n_mask | k_mask | m_mask | p_mask);

	reg |= ((_nkmp.n - nkmp->n.offset) << nkmp->n.shift) & n_mask;
	reg |= ((_nkmp.k - nkmp->k.offset) << nkmp->k.shift) & k_mask;
	reg |= ((_nkmp.m - nkmp->m.offset) << nkmp->m.shift) & m_mask;
	reg |= (ilog2(_nkmp.p) << nkmp->p.shift) & p_mask;

	writel(reg, nkmp->common.base + nkmp->common.reg);

	spin_unlock_irqrestore(nkmp->common.lock, flags);

	ccu_helper_wait_for_lock(&nkmp->common, nkmp->lock);

	return 0;
}

const struct clk_ops ccu_nkmp_ops = {
	.disable	= ccu_nkmp_disable,
	.enable		= ccu_nkmp_enable,
	.is_enabled	= ccu_nkmp_is_enabled,

	.recalc_rate	= ccu_nkmp_recalc_rate,
	.round_rate	= ccu_nkmp_round_rate,
	.set_rate	= ccu_nkmp_set_rate,
};
Commit	Line	Data
4f728b5d MR	1	/*
	2	* Copyright (C) 2016 Maxime Ripard
	3	* Maxime Ripard <maxime.ripard@free-electrons.com>
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of the GNU General Public License as
	7	* published by the Free Software Foundation; either version 2 of
	8	* the License, or (at your option) any later version.
	9	*/
	10
	11	#include <linux/clk-provider.h>
62e59c4e	12	#include <linux/io.h>
4f728b5d MR	13
	14	#include "ccu_gate.h"
	15	#include "ccu_nkmp.h"
	16
	17	struct _ccu_nkmp {
6e0d50da MR	18	unsigned long n, min_n, max_n;
	19	unsigned long k, min_k, max_k;
	20	unsigned long m, min_m, max_m;
	21	unsigned long p, min_p, max_p;
4f728b5d MR	22	};
4f728b5d MR	23
a5ebc336 JS	24	static unsigned long ccu_nkmp_calc_rate(unsigned long parent,
	25	unsigned long n, unsigned long k,
	26	unsigned long m, unsigned long p)
	27	{
	28	u64 rate = parent;
	29
	30	rate = n k;
	31	do_div(rate, m * p);
	32
	33	return rate;
	34	}
	35
4f728b5d MR	36	static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate,
	37	struct _ccu_nkmp *nkmp)
	38	{
	39	unsigned long best_rate = 0;
	40	unsigned long best_n = 0, best_k = 0, best_m = 0, best_p = 0;
	41	unsigned long _n, _k, _m, _p;
	42
6e0d50da MR	43	for (_k = nkmp->min_k; _k <= nkmp->max_k; _k++) {
	44	for (_n = nkmp->min_n; _n <= nkmp->max_n; _n++) {
	45	for (_m = nkmp->min_m; _m <= nkmp->max_m; _m++) {
	46	for (_p = nkmp->min_p; _p <= nkmp->max_p; _p <<= 1) {
ee28648c MR	47	unsigned long tmp_rate;
ee28648c MR	48
a5ebc336 JS	49	tmp_rate = ccu_nkmp_calc_rate(parent,
	50	_n, _k,
	51	_m, _p);
ee28648c MR	52
	53	if (tmp_rate > rate)
	54	continue;
	55
	56	if ((rate - tmp_rate) < (rate - best_rate)) {
	57	best_rate = tmp_rate;
	58	best_n = _n;
	59	best_k = _k;
	60	best_m = _m;
	61	best_p = _p;
	62	}
	63	}
4f728b5d MR	64	}
	65	}
	66	}
	67
	68	nkmp->n = best_n;
	69	nkmp->k = best_k;
	70	nkmp->m = best_m;
	71	nkmp->p = best_p;
	72	}
	73
	74	static void ccu_nkmp_disable(struct clk_hw *hw)
	75	{
	76	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
	77
	78	return ccu_gate_helper_disable(&nkmp->common, nkmp->enable);
	79	}
	80
	81	static int ccu_nkmp_enable(struct clk_hw *hw)
	82	{
	83	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
	84
	85	return ccu_gate_helper_enable(&nkmp->common, nkmp->enable);
	86	}
	87
	88	static int ccu_nkmp_is_enabled(struct clk_hw *hw)
	89	{
	90	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
	91
	92	return ccu_gate_helper_is_enabled(&nkmp->common, nkmp->enable);
	93	}
	94
	95	static unsigned long ccu_nkmp_recalc_rate(struct clk_hw *hw,
	96	unsigned long parent_rate)
	97	{
	98	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
a910f251	99	unsigned long n, m, k, p, rate;
4f728b5d MR	100	u32 reg;
	101
	102	reg = readl(nkmp->common.base + nkmp->common.reg);
	103
	104	n = reg >> nkmp->n.shift;
	105	n &= (1 << nkmp->n.width) - 1;
e66f81bb MR	106	n += nkmp->n.offset;
	107	if (!n)
	108	n++;
4f728b5d MR	109
	110	k = reg >> nkmp->k.shift;
	111	k &= (1 << nkmp->k.width) - 1;
e66f81bb MR	112	k += nkmp->k.offset;
	113	if (!k)
	114	k++;
4f728b5d MR	115
	116	m = reg >> nkmp->m.shift;
	117	m &= (1 << nkmp->m.width) - 1;
e66f81bb MR	118	m += nkmp->m.offset;
	119	if (!m)
	120	m++;
4f728b5d MR	121
	122	p = reg >> nkmp->p.shift;
	123	p &= (1 << nkmp->p.width) - 1;
	124
a910f251 IZ	125	rate = ccu_nkmp_calc_rate(parent_rate, n, k, m, 1 << p);
	126	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
	127	rate /= nkmp->fixed_post_div;
	128
	129	return rate;
4f728b5d MR	130	}
	131
	132	static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate,
	133	unsigned long *parent_rate)
	134	{
	135	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
	136	struct _ccu_nkmp _nkmp;
	137
a910f251 IZ	138	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
	139	rate *= nkmp->fixed_post_div;
	140
a8e5433c JS	141	if (nkmp->max_rate && rate > nkmp->max_rate) {
	142	rate = nkmp->max_rate;
	143	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
	144	rate /= nkmp->fixed_post_div;
	145	return rate;
	146	}
	147
4162c5ce	148	_nkmp.min_n = nkmp->n.min ?: 1;
0c3c8e13	149	_nkmp.max_n = nkmp->n.max ?: 1 << nkmp->n.width;
4162c5ce	150	_nkmp.min_k = nkmp->k.min ?: 1;
0c3c8e13	151	_nkmp.max_k = nkmp->k.max ?: 1 << nkmp->k.width;
6e0d50da	152	_nkmp.min_m = 1;
87ba9e59	153	_nkmp.max_m = nkmp->m.max ?: 1 << nkmp->m.width;
6e0d50da	154	_nkmp.min_p = 1;
87ba9e59	155	_nkmp.max_p = nkmp->p.max ?: 1 << ((1 << nkmp->p.width) - 1);
4f728b5d	156
87ba9e59	157	ccu_nkmp_find_best(*parent_rate, rate, &_nkmp);
4f728b5d	158
a910f251	159	rate = ccu_nkmp_calc_rate(*parent_rate, _nkmp.n, _nkmp.k,
a5ebc336	160	_nkmp.m, _nkmp.p);
a910f251 IZ	161	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
	162	rate = rate / nkmp->fixed_post_div;
	163
	164	return rate;
4f728b5d MR	165	}
	166
	167	static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate,
	168	unsigned long parent_rate)
	169	{
	170	struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
2abc330c	171	u32 n_mask = 0, k_mask = 0, m_mask = 0, p_mask = 0;
4f728b5d MR	172	struct _ccu_nkmp _nkmp;
	173	unsigned long flags;
	174	u32 reg;
	175
a910f251 IZ	176	if (nkmp->common.features & CCU_FEATURE_FIXED_POSTDIV)
	177	rate = rate * nkmp->fixed_post_div;
	178
95ad8ed9	179	_nkmp.min_n = nkmp->n.min ?: 1;
0c3c8e13	180	_nkmp.max_n = nkmp->n.max ?: 1 << nkmp->n.width;
95ad8ed9	181	_nkmp.min_k = nkmp->k.min ?: 1;
0c3c8e13	182	_nkmp.max_k = nkmp->k.max ?: 1 << nkmp->k.width;
6e0d50da	183	_nkmp.min_m = 1;
87ba9e59	184	_nkmp.max_m = nkmp->m.max ?: 1 << nkmp->m.width;
6e0d50da	185	_nkmp.min_p = 1;
87ba9e59	186	_nkmp.max_p = nkmp->p.max ?: 1 << ((1 << nkmp->p.width) - 1);
4f728b5d MR	187
	188	ccu_nkmp_find_best(parent_rate, rate, &_nkmp);
	189
1054e4dd JS	190	/*
	191	* If width is 0, GENMASK() macro may not generate expected mask (0)
	192	* as it falls under undefined behaviour by C standard due to shifts
	193	* which are equal or greater than width of left operand. This can
	194	* be easily avoided by explicitly checking if width is 0.
	195	*/
2abc330c JS	196	if (nkmp->n.width)
	197	n_mask = GENMASK(nkmp->n.width + nkmp->n.shift - 1,
	198	nkmp->n.shift);
	199	if (nkmp->k.width)
	200	k_mask = GENMASK(nkmp->k.width + nkmp->k.shift - 1,
	201	nkmp->k.shift);
	202	if (nkmp->m.width)
	203	m_mask = GENMASK(nkmp->m.width + nkmp->m.shift - 1,
	204	nkmp->m.shift);
	205	if (nkmp->p.width)
	206	p_mask = GENMASK(nkmp->p.width + nkmp->p.shift - 1,
	207	nkmp->p.shift);
d897ef56	208
4f728b5d MR	209	spin_lock_irqsave(nkmp->common.lock, flags);
	210
	211	reg = readl(nkmp->common.base + nkmp->common.reg);
d897ef56 JS	212	reg &= ~(n_mask \| k_mask \| m_mask \| p_mask);
	213
	214	reg \|= ((_nkmp.n - nkmp->n.offset) << nkmp->n.shift) & n_mask;
	215	reg \|= ((_nkmp.k - nkmp->k.offset) << nkmp->k.shift) & k_mask;
	216	reg \|= ((_nkmp.m - nkmp->m.offset) << nkmp->m.shift) & m_mask;
	217	reg \|= (ilog2(_nkmp.p) << nkmp->p.shift) & p_mask;
4f728b5d MR	218
	219	writel(reg, nkmp->common.base + nkmp->common.reg);
	220
	221	spin_unlock_irqrestore(nkmp->common.lock, flags);
	222
	223	ccu_helper_wait_for_lock(&nkmp->common, nkmp->lock);
	224
	225	return 0;
	226	}
	227
	228	const struct clk_ops ccu_nkmp_ops = {
	229	.disable = ccu_nkmp_disable,
	230	.enable = ccu_nkmp_enable,
	231	.is_enabled = ccu_nkmp_is_enabled,
	232
	233	.recalc_rate = ccu_nkmp_recalc_rate,
	234	.round_rate = ccu_nkmp_round_rate,
	235	.set_rate = ccu_nkmp_set_rate,
	236	};