Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
adbfb005 MR |
2 | /* |
3 | * Copyright (C) 2016 Maxime Ripard | |
4 | * Maxime Ripard <maxime.ripard@free-electrons.com> | |
adbfb005 MR |
5 | */ |
6 | ||
7 | #include <linux/clk-provider.h> | |
62e59c4e | 8 | #include <linux/io.h> |
adbfb005 MR |
9 | |
10 | #include "ccu_gate.h" | |
11 | #include "ccu_nk.h" | |
12 | ||
b8302c72 | 13 | struct _ccu_nk { |
6e0d50da MR |
14 | unsigned long n, min_n, max_n; |
15 | unsigned long k, min_k, max_k; | |
b8302c72 MR |
16 | }; |
17 | ||
657f477a SH |
18 | static unsigned long ccu_nk_find_best(unsigned long parent, unsigned long rate, |
19 | struct _ccu_nk *nk) | |
adbfb005 MR |
20 | { |
21 | unsigned long best_rate = 0; | |
22 | unsigned int best_k = 0, best_n = 0; | |
23 | unsigned int _k, _n; | |
24 | ||
6e0d50da MR |
25 | for (_k = nk->min_k; _k <= nk->max_k; _k++) { |
26 | for (_n = nk->min_n; _n <= nk->max_n; _n++) { | |
adbfb005 MR |
27 | unsigned long tmp_rate = parent * _n * _k; |
28 | ||
29 | if (tmp_rate > rate) | |
30 | continue; | |
31 | ||
32 | if ((rate - tmp_rate) < (rate - best_rate)) { | |
33 | best_rate = tmp_rate; | |
34 | best_k = _k; | |
35 | best_n = _n; | |
36 | } | |
37 | } | |
38 | } | |
39 | ||
b8302c72 MR |
40 | nk->k = best_k; |
41 | nk->n = best_n; | |
657f477a SH |
42 | |
43 | return best_rate; | |
adbfb005 MR |
44 | } |
45 | ||
46 | static void ccu_nk_disable(struct clk_hw *hw) | |
47 | { | |
48 | struct ccu_nk *nk = hw_to_ccu_nk(hw); | |
49 | ||
50 | return ccu_gate_helper_disable(&nk->common, nk->enable); | |
51 | } | |
52 | ||
53 | static int ccu_nk_enable(struct clk_hw *hw) | |
54 | { | |
55 | struct ccu_nk *nk = hw_to_ccu_nk(hw); | |
56 | ||
57 | return ccu_gate_helper_enable(&nk->common, nk->enable); | |
58 | } | |
59 | ||
60 | static int ccu_nk_is_enabled(struct clk_hw *hw) | |
61 | { | |
62 | struct ccu_nk *nk = hw_to_ccu_nk(hw); | |
63 | ||
64 | return ccu_gate_helper_is_enabled(&nk->common, nk->enable); | |
65 | } | |
66 | ||
67 | static unsigned long ccu_nk_recalc_rate(struct clk_hw *hw, | |
68 | unsigned long parent_rate) | |
69 | { | |
70 | struct ccu_nk *nk = hw_to_ccu_nk(hw); | |
71 | unsigned long rate, n, k; | |
72 | u32 reg; | |
73 | ||
74 | reg = readl(nk->common.base + nk->common.reg); | |
75 | ||
76 | n = reg >> nk->n.shift; | |
77 | n &= (1 << nk->n.width) - 1; | |
e66f81bb MR |
78 | n += nk->n.offset; |
79 | if (!n) | |
80 | n++; | |
adbfb005 MR |
81 | |
82 | k = reg >> nk->k.shift; | |
83 | k &= (1 << nk->k.width) - 1; | |
e66f81bb MR |
84 | k += nk->k.offset; |
85 | if (!k) | |
86 | k++; | |
adbfb005 | 87 | |
e66f81bb | 88 | rate = parent_rate * n * k; |
adbfb005 MR |
89 | if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) |
90 | rate /= nk->fixed_post_div; | |
91 | ||
92 | return rate; | |
93 | } | |
94 | ||
95 | static long ccu_nk_round_rate(struct clk_hw *hw, unsigned long rate, | |
96 | unsigned long *parent_rate) | |
97 | { | |
98 | struct ccu_nk *nk = hw_to_ccu_nk(hw); | |
b8302c72 | 99 | struct _ccu_nk _nk; |
adbfb005 MR |
100 | |
101 | if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) | |
102 | rate *= nk->fixed_post_div; | |
103 | ||
4162c5ce | 104 | _nk.min_n = nk->n.min ?: 1; |
0c3c8e13 | 105 | _nk.max_n = nk->n.max ?: 1 << nk->n.width; |
4162c5ce | 106 | _nk.min_k = nk->k.min ?: 1; |
0c3c8e13 | 107 | _nk.max_k = nk->k.max ?: 1 << nk->k.width; |
b8302c72 | 108 | |
657f477a | 109 | rate = ccu_nk_find_best(*parent_rate, rate, &_nk); |
adbfb005 | 110 | |
adbfb005 MR |
111 | if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) |
112 | rate = rate / nk->fixed_post_div; | |
113 | ||
114 | return rate; | |
115 | } | |
116 | ||
117 | static int ccu_nk_set_rate(struct clk_hw *hw, unsigned long rate, | |
118 | unsigned long parent_rate) | |
119 | { | |
120 | struct ccu_nk *nk = hw_to_ccu_nk(hw); | |
121 | unsigned long flags; | |
b8302c72 | 122 | struct _ccu_nk _nk; |
adbfb005 MR |
123 | u32 reg; |
124 | ||
125 | if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV) | |
126 | rate = rate * nk->fixed_post_div; | |
127 | ||
4162c5ce | 128 | _nk.min_n = nk->n.min ?: 1; |
0c3c8e13 | 129 | _nk.max_n = nk->n.max ?: 1 << nk->n.width; |
4162c5ce | 130 | _nk.min_k = nk->k.min ?: 1; |
0c3c8e13 | 131 | _nk.max_k = nk->k.max ?: 1 << nk->k.width; |
b8302c72 MR |
132 | |
133 | ccu_nk_find_best(parent_rate, rate, &_nk); | |
adbfb005 MR |
134 | |
135 | spin_lock_irqsave(nk->common.lock, flags); | |
136 | ||
137 | reg = readl(nk->common.base + nk->common.reg); | |
138 | reg &= ~GENMASK(nk->n.width + nk->n.shift - 1, nk->n.shift); | |
139 | reg &= ~GENMASK(nk->k.width + nk->k.shift - 1, nk->k.shift); | |
140 | ||
e66f81bb MR |
141 | reg |= (_nk.k - nk->k.offset) << nk->k.shift; |
142 | reg |= (_nk.n - nk->n.offset) << nk->n.shift; | |
143 | writel(reg, nk->common.base + nk->common.reg); | |
adbfb005 MR |
144 | |
145 | spin_unlock_irqrestore(nk->common.lock, flags); | |
146 | ||
147 | ccu_helper_wait_for_lock(&nk->common, nk->lock); | |
148 | ||
149 | return 0; | |
150 | } | |
151 | ||
152 | const struct clk_ops ccu_nk_ops = { | |
153 | .disable = ccu_nk_disable, | |
154 | .enable = ccu_nk_enable, | |
155 | .is_enabled = ccu_nk_is_enabled, | |
156 | ||
157 | .recalc_rate = ccu_nk_recalc_rate, | |
158 | .round_rate = ccu_nk_round_rate, | |
159 | .set_rate = ccu_nk_set_rate, | |
160 | }; | |
551b62b1 | 161 | EXPORT_SYMBOL_NS_GPL(ccu_nk_ops, SUNXI_CCU); |