xref: /openbmc/linux/drivers/clk/tegra/clk-pll-out.c (revision 20e2fc42)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/io.h>
8 #include <linux/err.h>
9 #include <linux/delay.h>
10 #include <linux/slab.h>
11 #include <linux/clk-provider.h>
12 
13 #include "clk.h"
14 
15 #define pll_out_enb(p) (BIT(p->enb_bit_idx))
16 #define pll_out_rst(p) (BIT(p->rst_bit_idx))
17 
18 static int clk_pll_out_is_enabled(struct clk_hw *hw)
19 {
20 	struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
21 	u32 val = readl_relaxed(pll_out->reg);
22 	int state;
23 
24 	state = (val & pll_out_enb(pll_out)) ? 1 : 0;
25 	if (!(val & (pll_out_rst(pll_out))))
26 		state = 0;
27 	return state;
28 }
29 
30 static int clk_pll_out_enable(struct clk_hw *hw)
31 {
32 	struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
33 	unsigned long flags = 0;
34 	u32 val;
35 
36 	if (pll_out->lock)
37 		spin_lock_irqsave(pll_out->lock, flags);
38 
39 	val = readl_relaxed(pll_out->reg);
40 
41 	val |= (pll_out_enb(pll_out) | pll_out_rst(pll_out));
42 
43 	writel_relaxed(val, pll_out->reg);
44 	udelay(2);
45 
46 	if (pll_out->lock)
47 		spin_unlock_irqrestore(pll_out->lock, flags);
48 
49 	return 0;
50 }
51 
52 static void clk_pll_out_disable(struct clk_hw *hw)
53 {
54 	struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
55 	unsigned long flags = 0;
56 	u32 val;
57 
58 	if (pll_out->lock)
59 		spin_lock_irqsave(pll_out->lock, flags);
60 
61 	val = readl_relaxed(pll_out->reg);
62 
63 	val &= ~(pll_out_enb(pll_out) | pll_out_rst(pll_out));
64 
65 	writel_relaxed(val, pll_out->reg);
66 	udelay(2);
67 
68 	if (pll_out->lock)
69 		spin_unlock_irqrestore(pll_out->lock, flags);
70 }
71 
72 const struct clk_ops tegra_clk_pll_out_ops = {
73 	.is_enabled = clk_pll_out_is_enabled,
74 	.enable = clk_pll_out_enable,
75 	.disable = clk_pll_out_disable,
76 };
77 
78 struct clk *tegra_clk_register_pll_out(const char *name,
79 		const char *parent_name, void __iomem *reg, u8 enb_bit_idx,
80 		u8 rst_bit_idx, unsigned long flags, u8 pll_out_flags,
81 		spinlock_t *lock)
82 {
83 	struct tegra_clk_pll_out *pll_out;
84 	struct clk *clk;
85 	struct clk_init_data init;
86 
87 	pll_out = kzalloc(sizeof(*pll_out), GFP_KERNEL);
88 	if (!pll_out)
89 		return ERR_PTR(-ENOMEM);
90 
91 	init.name = name;
92 	init.ops = &tegra_clk_pll_out_ops;
93 	init.parent_names = (parent_name ? &parent_name : NULL);
94 	init.num_parents = (parent_name ? 1 : 0);
95 	init.flags = flags;
96 
97 	pll_out->reg = reg;
98 	pll_out->enb_bit_idx = enb_bit_idx;
99 	pll_out->rst_bit_idx = rst_bit_idx;
100 	pll_out->flags = pll_out_flags;
101 	pll_out->lock = lock;
102 
103 	/* Data in .init is copied by clk_register(), so stack variable OK */
104 	pll_out->hw.init = &init;
105 
106 	clk = clk_register(NULL, &pll_out->hw);
107 	if (IS_ERR(clk))
108 		kfree(pll_out);
109 
110 	return clk;
111 }
112