1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2016 Maxime Ripard
4 * Maxime Ripard <maxime.ripard@free-electrons.com>
5 */
6
7 #include <linux/clk-provider.h>
8 #include <linux/io.h>
9 #include <linux/spinlock.h>
10
11 #include "ccu_frac.h"
12
ccu_frac_helper_is_enabled(struct ccu_common * common,struct ccu_frac_internal * cf)13 bool ccu_frac_helper_is_enabled(struct ccu_common *common,
14 struct ccu_frac_internal *cf)
15 {
16 if (!(common->features & CCU_FEATURE_FRACTIONAL))
17 return false;
18
19 return !(readl(common->base + common->reg) & cf->enable);
20 }
21 EXPORT_SYMBOL_NS_GPL(ccu_frac_helper_is_enabled, SUNXI_CCU);
22
ccu_frac_helper_enable(struct ccu_common * common,struct ccu_frac_internal * cf)23 void ccu_frac_helper_enable(struct ccu_common *common,
24 struct ccu_frac_internal *cf)
25 {
26 unsigned long flags;
27 u32 reg;
28
29 if (!(common->features & CCU_FEATURE_FRACTIONAL))
30 return;
31
32 spin_lock_irqsave(common->lock, flags);
33 reg = readl(common->base + common->reg);
34 writel(reg & ~cf->enable, common->base + common->reg);
35 spin_unlock_irqrestore(common->lock, flags);
36 }
37 EXPORT_SYMBOL_NS_GPL(ccu_frac_helper_enable, SUNXI_CCU);
38
ccu_frac_helper_disable(struct ccu_common * common,struct ccu_frac_internal * cf)39 void ccu_frac_helper_disable(struct ccu_common *common,
40 struct ccu_frac_internal *cf)
41 {
42 unsigned long flags;
43 u32 reg;
44
45 if (!(common->features & CCU_FEATURE_FRACTIONAL))
46 return;
47
48 spin_lock_irqsave(common->lock, flags);
49 reg = readl(common->base + common->reg);
50 writel(reg | cf->enable, common->base + common->reg);
51 spin_unlock_irqrestore(common->lock, flags);
52 }
53 EXPORT_SYMBOL_NS_GPL(ccu_frac_helper_disable, SUNXI_CCU);
54
ccu_frac_helper_has_rate(struct ccu_common * common,struct ccu_frac_internal * cf,unsigned long rate)55 bool ccu_frac_helper_has_rate(struct ccu_common *common,
56 struct ccu_frac_internal *cf,
57 unsigned long rate)
58 {
59 if (!(common->features & CCU_FEATURE_FRACTIONAL))
60 return false;
61
62 return (cf->rates[0] == rate) || (cf->rates[1] == rate);
63 }
64 EXPORT_SYMBOL_NS_GPL(ccu_frac_helper_has_rate, SUNXI_CCU);
65
ccu_frac_helper_read_rate(struct ccu_common * common,struct ccu_frac_internal * cf)66 unsigned long ccu_frac_helper_read_rate(struct ccu_common *common,
67 struct ccu_frac_internal *cf)
68 {
69 u32 reg;
70
71 pr_debug("%s: Read fractional\n", clk_hw_get_name(&common->hw));
72
73 if (!(common->features & CCU_FEATURE_FRACTIONAL))
74 return 0;
75
76 pr_debug("%s: clock is fractional (rates %lu and %lu)\n",
77 clk_hw_get_name(&common->hw), cf->rates[0], cf->rates[1]);
78
79 reg = readl(common->base + common->reg);
80
81 pr_debug("%s: clock reg is 0x%x (select is 0x%x)\n",
82 clk_hw_get_name(&common->hw), reg, cf->select);
83
84 return (reg & cf->select) ? cf->rates[1] : cf->rates[0];
85 }
86 EXPORT_SYMBOL_NS_GPL(ccu_frac_helper_read_rate, SUNXI_CCU);
87
ccu_frac_helper_set_rate(struct ccu_common * common,struct ccu_frac_internal * cf,unsigned long rate,u32 lock)88 int ccu_frac_helper_set_rate(struct ccu_common *common,
89 struct ccu_frac_internal *cf,
90 unsigned long rate, u32 lock)
91 {
92 unsigned long flags;
93 u32 reg, sel;
94
95 if (!(common->features & CCU_FEATURE_FRACTIONAL))
96 return -EINVAL;
97
98 if (cf->rates[0] == rate)
99 sel = 0;
100 else if (cf->rates[1] == rate)
101 sel = cf->select;
102 else
103 return -EINVAL;
104
105 spin_lock_irqsave(common->lock, flags);
106 reg = readl(common->base + common->reg);
107 reg &= ~cf->select;
108 writel(reg | sel, common->base + common->reg);
109 spin_unlock_irqrestore(common->lock, flags);
110
111 ccu_helper_wait_for_lock(common, lock);
112
113 return 0;
114 }
115 EXPORT_SYMBOL_NS_GPL(ccu_frac_helper_set_rate, SUNXI_CCU);
116