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authorMaxime Ripard <maxime.ripard@free-electrons.com>2016-06-29 15:05:33 -0400
committerMichael Turquette <mturquette@baylibre.com>2016-07-08 21:05:06 -0400
commit4f728b5db7cb125af71e5da8154ac3b72653d819 (patch)
treecf8883d002ee6d51f9558796ee471280407f7f5f
parentdf6561e60244c0283340286664b0baf67e846599 (diff)
clk: sunxi-ng: Add N-K-M-P factor clock
Introduce support for clocks that use a combination of two linear multipliers (N and K factors), one linear divider (M) and one power of two divider (P). Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Michael Turquette <mturquette@baylibre.com> Link: lkml.kernel.org/r/20160629190535.11855-13-maxime.ripard@free-electrons.com
Diffstat
-rw-r--r--drivers/clk/sunxi-ng/Kconfig5
-rw-r--r--drivers/clk/sunxi-ng/Makefile1
-rw-r--r--drivers/clk/sunxi-ng/ccu_nkmp.c167
-rw-r--r--drivers/clk/sunxi-ng/ccu_nkmp.h71
4 files changed, 244 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/Kconfig b/drivers/clk/sunxi-ng/Kconfig
index 4c571b86bfd1..24fc9e4cc546 100644
--- a/drivers/clk/sunxi-ng/Kconfig
+++ b/drivers/clk/sunxi-ng/Kconfig
@@ -33,6 +33,11 @@ config SUNXI_CCU_NKM
33 select RATIONAL 33 select RATIONAL
34 select SUNXI_CCU_GATE 34 select SUNXI_CCU_GATE
35 35
36config SUNXI_CCU_NKMP
37 bool
38 select RATIONAL
39 select SUNXI_CCU_GATE
40
36config SUNXI_CCU_NM 41config SUNXI_CCU_NM
37 bool 42 bool
38 select RATIONAL 43 select RATIONAL
diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile
index 2d6fdca0d3cc..5c342cc698d2 100644
--- a/drivers/clk/sunxi-ng/Makefile
+++ b/drivers/clk/sunxi-ng/Makefile
@@ -12,5 +12,6 @@ obj-$(CONFIG_SUNXI_CCU_PHASE) += ccu_phase.o
12# Multi-factor clocks 12# Multi-factor clocks
13obj-$(CONFIG_SUNXI_CCU_NK) += ccu_nk.o 13obj-$(CONFIG_SUNXI_CCU_NK) += ccu_nk.o
14obj-$(CONFIG_SUNXI_CCU_NKM) += ccu_nkm.o 14obj-$(CONFIG_SUNXI_CCU_NKM) += ccu_nkm.o
15obj-$(CONFIG_SUNXI_CCU_NKMP) += ccu_nkmp.o
15obj-$(CONFIG_SUNXI_CCU_NM) += ccu_nm.o 16obj-$(CONFIG_SUNXI_CCU_NM) += ccu_nm.o
16obj-$(CONFIG_SUNXI_CCU_MP) += ccu_mp.o 17obj-$(CONFIG_SUNXI_CCU_MP) += ccu_mp.o
diff --git a/drivers/clk/sunxi-ng/ccu_nkmp.c b/drivers/clk/sunxi-ng/ccu_nkmp.c
new file mode 100644
index 000000000000..9f2b98e19dc9
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_nkmp.c
@@ -0,0 +1,167 @@
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>
12#include <linux/rational.h>
13
14#include "ccu_gate.h"
15#include "ccu_nkmp.h"
16
17struct _ccu_nkmp {
18 unsigned long n, max_n;
19 unsigned long k, max_k;
20 unsigned long m, max_m;
21 unsigned long p, max_p;
22};
23
24static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate,
25 struct _ccu_nkmp *nkmp)
26{
27 unsigned long best_rate = 0;
28 unsigned long best_n = 0, best_k = 0, best_m = 0, best_p = 0;
29 unsigned long _n, _k, _m, _p;
30
31 for (_k = 1; _k <= nkmp->max_k; _k++) {
32 for (_p = 0; _p <= nkmp->max_p; _p++) {
33 unsigned long tmp_rate;
34
35 rational_best_approximation(rate / _k, parent >> _p,
36 nkmp->max_n, nkmp->max_m,
37 &_n, &_m);
38
39 tmp_rate = (parent * _n * _k >> _p) / _m;
40
41 if (tmp_rate > rate)
42 continue;
43
44 if ((rate - tmp_rate) < (rate - best_rate)) {
45 best_rate = tmp_rate;
46 best_n = _n;
47 best_k = _k;
48 best_m = _m;
49 best_p = _p;
50 }
51 }
52 }
53
54 nkmp->n = best_n;
55 nkmp->k = best_k;
56 nkmp->m = best_m;
57 nkmp->p = best_p;
58}
59
60static void ccu_nkmp_disable(struct clk_hw *hw)
61{
62 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
63
64 return ccu_gate_helper_disable(&nkmp->common, nkmp->enable);
65}
66
67static int ccu_nkmp_enable(struct clk_hw *hw)
68{
69 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
70
71 return ccu_gate_helper_enable(&nkmp->common, nkmp->enable);
72}
73
74static int ccu_nkmp_is_enabled(struct clk_hw *hw)
75{
76 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
77
78 return ccu_gate_helper_is_enabled(&nkmp->common, nkmp->enable);
79}
80
81static unsigned long ccu_nkmp_recalc_rate(struct clk_hw *hw,
82 unsigned long parent_rate)
83{
84 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
85 unsigned long n, m, k, p;
86 u32 reg;
87
88 reg = readl(nkmp->common.base + nkmp->common.reg);
89
90 n = reg >> nkmp->n.shift;
91 n &= (1 << nkmp->n.width) - 1;
92
93 k = reg >> nkmp->k.shift;
94 k &= (1 << nkmp->k.width) - 1;
95
96 m = reg >> nkmp->m.shift;
97 m &= (1 << nkmp->m.width) - 1;
98
99 p = reg >> nkmp->p.shift;
100 p &= (1 << nkmp->p.width) - 1;
101
102 return (parent_rate * (n + 1) * (k + 1) >> p) / (m + 1);
103}
104
105static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate,
106 unsigned long *parent_rate)
107{
108 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
109 struct _ccu_nkmp _nkmp;
110
111 _nkmp.max_n = 1 << nkmp->n.width;
112 _nkmp.max_k = 1 << nkmp->k.width;
113 _nkmp.max_m = 1 << nkmp->m.width;
114 _nkmp.max_p = (1 << nkmp->p.width) - 1;
115
116 ccu_nkmp_find_best(*parent_rate, rate,
117 &_nkmp);
118
119 return (*parent_rate * _nkmp.n * _nkmp.k >> _nkmp.p) / _nkmp.m;
120}
121
122static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate,
123 unsigned long parent_rate)
124{
125 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
126 struct _ccu_nkmp _nkmp;
127 unsigned long flags;
128 u32 reg;
129
130 _nkmp.max_n = 1 << nkmp->n.width;
131 _nkmp.max_k = 1 << nkmp->k.width;
132 _nkmp.max_m = 1 << nkmp->m.width;
133 _nkmp.max_p = (1 << nkmp->p.width) - 1;
134
135 ccu_nkmp_find_best(parent_rate, rate, &_nkmp);
136
137 spin_lock_irqsave(nkmp->common.lock, flags);
138
139 reg = readl(nkmp->common.base + nkmp->common.reg);
140 reg &= ~GENMASK(nkmp->n.width + nkmp->n.shift - 1, nkmp->n.shift);
141 reg &= ~GENMASK(nkmp->k.width + nkmp->k.shift - 1, nkmp->k.shift);
142 reg &= ~GENMASK(nkmp->m.width + nkmp->m.shift - 1, nkmp->m.shift);
143 reg &= ~GENMASK(nkmp->p.width + nkmp->p.shift - 1, nkmp->p.shift);
144
145 reg |= (_nkmp.n - 1) << nkmp->n.shift;
146 reg |= (_nkmp.k - 1) << nkmp->k.shift;
147 reg |= (_nkmp.m - 1) << nkmp->m.shift;
148 reg |= _nkmp.p << nkmp->p.shift;
149
150 writel(reg, nkmp->common.base + nkmp->common.reg);
151
152 spin_unlock_irqrestore(nkmp->common.lock, flags);
153
154 ccu_helper_wait_for_lock(&nkmp->common, nkmp->lock);
155
156 return 0;
157}
158
159const struct clk_ops ccu_nkmp_ops = {
160 .disable = ccu_nkmp_disable,
161 .enable = ccu_nkmp_enable,
162 .is_enabled = ccu_nkmp_is_enabled,
163
164 .recalc_rate = ccu_nkmp_recalc_rate,
165 .round_rate = ccu_nkmp_round_rate,
166 .set_rate = ccu_nkmp_set_rate,
167};
diff --git a/drivers/clk/sunxi-ng/ccu_nkmp.h b/drivers/clk/sunxi-ng/ccu_nkmp.h
new file mode 100644
index 000000000000..5adb0c92a614
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_nkmp.h
@@ -0,0 +1,71 @@
1/*
2 * Copyright (c) 2016 Maxime Ripard. All rights reserved.
3 *
4 * This software is licensed under the terms of the GNU General Public
5 * License version 2, as published by the Free Software Foundation, and
6 * may be copied, distributed, and modified under those terms.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 */
13
14#ifndef _CCU_NKMP_H_
15#define _CCU_NKMP_H_
16
17#include <linux/clk-provider.h>
18
19#include "ccu_common.h"
20#include "ccu_div.h"
21#include "ccu_mult.h"
22
23/*
24 * struct ccu_nkmp - Definition of an N-K-M-P clock
25 *
26 * Clocks based on the formula parent * N * K >> P / M
27 */
28struct ccu_nkmp {
29 u32 enable;
30 u32 lock;
31
32 struct _ccu_mult n;
33 struct _ccu_mult k;
34 struct _ccu_div m;
35 struct _ccu_div p;
36
37 struct ccu_common common;
38};
39
40#define SUNXI_CCU_NKMP_WITH_GATE_LOCK(_struct, _name, _parent, _reg, \
41 _nshift, _nwidth, \
42 _kshift, _kwidth, \
43 _mshift, _mwidth, \
44 _pshift, _pwidth, \
45 _gate, _lock, _flags) \
46 struct ccu_nkmp _struct = { \
47 .enable = _gate, \
48 .lock = _lock, \
49 .n = _SUNXI_CCU_MULT(_nshift, _nwidth), \
50 .k = _SUNXI_CCU_MULT(_kshift, _kwidth), \
51 .m = _SUNXI_CCU_DIV(_mshift, _mwidth), \
52 .p = _SUNXI_CCU_DIV(_pshift, _pwidth), \
53 .common = { \
54 .reg = _reg, \
55 .hw.init = CLK_HW_INIT(_name, \
56 _parent, \
57 &ccu_nkmp_ops, \
58 _flags), \
59 }, \
60 }
61
62static inline struct ccu_nkmp *hw_to_ccu_nkmp(struct clk_hw *hw)
63{
64 struct ccu_common *common = hw_to_ccu_common(hw);
65
66 return container_of(common, struct ccu_nkmp, common);
67}
68
69extern const struct clk_ops ccu_nkmp_ops;
70
71#endif /* _CCU_NKMP_H_ */
generated by cgit v1.2.2 (git 2.25.0) at 2025-08-22 07:15:50 -0400