1 /*
2 * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
15 */
16
17 #include <linux/kernel.h>
18 #include <linux/io.h>
19 #include <linux/err.h>
20 #include <linux/delay.h>
21 #include <linux/slab.h>
22 #include <linux/clk-provider.h>
23
24 #include "clk.h"
25
26 #define pll_out_enb(p) (BIT(p->enb_bit_idx))
27 #define pll_out_rst(p) (BIT(p->rst_bit_idx))
28
clk_pll_out_is_enabled(struct clk_hw * hw)29 static int clk_pll_out_is_enabled(struct clk_hw *hw)
30 {
31 struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
32 u32 val = readl_relaxed(pll_out->reg);
33 int state;
34
35 state = (val & pll_out_enb(pll_out)) ? 1 : 0;
36 if (!(val & (pll_out_rst(pll_out))))
37 state = 0;
38 return state;
39 }
40
clk_pll_out_enable(struct clk_hw * hw)41 static int clk_pll_out_enable(struct clk_hw *hw)
42 {
43 struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
44 unsigned long flags = 0;
45 u32 val;
46
47 if (pll_out->lock)
48 spin_lock_irqsave(pll_out->lock, flags);
49
50 val = readl_relaxed(pll_out->reg);
51
52 val |= (pll_out_enb(pll_out) | pll_out_rst(pll_out));
53
54 writel_relaxed(val, pll_out->reg);
55 udelay(2);
56
57 if (pll_out->lock)
58 spin_unlock_irqrestore(pll_out->lock, flags);
59
60 return 0;
61 }
62
clk_pll_out_disable(struct clk_hw * hw)63 static void clk_pll_out_disable(struct clk_hw *hw)
64 {
65 struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
66 unsigned long flags = 0;
67 u32 val;
68
69 if (pll_out->lock)
70 spin_lock_irqsave(pll_out->lock, flags);
71
72 val = readl_relaxed(pll_out->reg);
73
74 val &= ~(pll_out_enb(pll_out) | pll_out_rst(pll_out));
75
76 writel_relaxed(val, pll_out->reg);
77 udelay(2);
78
79 if (pll_out->lock)
80 spin_unlock_irqrestore(pll_out->lock, flags);
81 }
82
83 const struct clk_ops tegra_clk_pll_out_ops = {
84 .is_enabled = clk_pll_out_is_enabled,
85 .enable = clk_pll_out_enable,
86 .disable = clk_pll_out_disable,
87 };
88
tegra_clk_register_pll_out(const char * name,const char * parent_name,void __iomem * reg,u8 enb_bit_idx,u8 rst_bit_idx,unsigned long flags,u8 pll_out_flags,spinlock_t * lock)89 struct clk *tegra_clk_register_pll_out(const char *name,
90 const char *parent_name, void __iomem *reg, u8 enb_bit_idx,
91 u8 rst_bit_idx, unsigned long flags, u8 pll_out_flags,
92 spinlock_t *lock)
93 {
94 struct tegra_clk_pll_out *pll_out;
95 struct clk *clk;
96 struct clk_init_data init;
97
98 pll_out = kzalloc(sizeof(*pll_out), GFP_KERNEL);
99 if (!pll_out)
100 return ERR_PTR(-ENOMEM);
101
102 init.name = name;
103 init.ops = &tegra_clk_pll_out_ops;
104 init.parent_names = (parent_name ? &parent_name : NULL);
105 init.num_parents = (parent_name ? 1 : 0);
106 init.flags = flags;
107
108 pll_out->reg = reg;
109 pll_out->enb_bit_idx = enb_bit_idx;
110 pll_out->rst_bit_idx = rst_bit_idx;
111 pll_out->flags = pll_out_flags;
112 pll_out->lock = lock;
113
114 /* Data in .init is copied by clk_register(), so stack variable OK */
115 pll_out->hw.init = &init;
116
117 clk = clk_register(NULL, &pll_out->hw);
118 if (IS_ERR(clk))
119 kfree(pll_out);
120
121 return clk;
122 }
123