1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2012, 2013, NVIDIA CORPORATION. All rights reserved.
4 */
5
6#include <linux/io.h>
7#include <linux/clk-provider.h>
8#include <linux/of.h>
9#include <linux/of_address.h>
10#include <linux/delay.h>
11#include <linux/export.h>
12#include <linux/clk/tegra.h>
13
14#include "clk.h"
15#include "clk-id.h"
16
17#define OSC_CTRL 0x50
18#define OSC_CTRL_OSC_FREQ_SHIFT 28
19#define OSC_CTRL_PLL_REF_DIV_SHIFT 26
20#define OSC_CTRL_MASK (0x3f2 | \
21 (0xf << OSC_CTRL_OSC_FREQ_SHIFT))
22
23static u32 osc_ctrl_ctx;
24
25int __init tegra_osc_clk_init(void __iomem *clk_base, struct tegra_clk *clks,
26 unsigned long *input_freqs, unsigned int num,
27 unsigned int clk_m_div, unsigned long *osc_freq,
28 unsigned long *pll_ref_freq)
29{
30 struct clk *clk, *osc;
31 struct clk **dt_clk;
32 u32 val, pll_ref_div;
33 unsigned osc_idx;
34
35 val = readl_relaxed(clk_base + OSC_CTRL);
36 osc_ctrl_ctx = val & OSC_CTRL_MASK;
37 osc_idx = val >> OSC_CTRL_OSC_FREQ_SHIFT;
38
39 if (osc_idx < num)
40 *osc_freq = input_freqs[osc_idx];
41 else
42 *osc_freq = 0;
43
44 if (!*osc_freq) {
45 WARN_ON(1);
46 return -EINVAL;
47 }
48
49 dt_clk = tegra_lookup_dt_id(clk_id: tegra_clk_osc, tegra_clk: clks);
50 if (!dt_clk)
51 return 0;
52
53 osc = clk_register_fixed_rate(NULL, name: "osc", NULL, flags: 0, fixed_rate: *osc_freq);
54 *dt_clk = osc;
55
56 /* osc_div2 */
57 dt_clk = tegra_lookup_dt_id(clk_id: tegra_clk_osc_div2, tegra_clk: clks);
58 if (dt_clk) {
59 clk = clk_register_fixed_factor(NULL, name: "osc_div2", parent_name: "osc",
60 flags: 0, mult: 1, div: 2);
61 *dt_clk = clk;
62 }
63
64 /* osc_div4 */
65 dt_clk = tegra_lookup_dt_id(clk_id: tegra_clk_osc_div4, tegra_clk: clks);
66 if (dt_clk) {
67 clk = clk_register_fixed_factor(NULL, name: "osc_div4", parent_name: "osc",
68 flags: 0, mult: 1, div: 4);
69 *dt_clk = clk;
70 }
71
72 dt_clk = tegra_lookup_dt_id(clk_id: tegra_clk_clk_m, tegra_clk: clks);
73 if (!dt_clk)
74 return 0;
75
76 clk = clk_register_fixed_factor(NULL, name: "clk_m", parent_name: "osc",
77 flags: 0, mult: 1, div: clk_m_div);
78 *dt_clk = clk;
79
80 /* pll_ref */
81 val = (val >> OSC_CTRL_PLL_REF_DIV_SHIFT) & 3;
82 pll_ref_div = 1 << val;
83 dt_clk = tegra_lookup_dt_id(clk_id: tegra_clk_pll_ref, tegra_clk: clks);
84 if (!dt_clk)
85 return 0;
86
87 clk = clk_register_fixed_factor(NULL, name: "pll_ref", parent_name: "osc",
88 flags: 0, mult: 1, div: pll_ref_div);
89 *dt_clk = clk;
90
91 if (pll_ref_freq)
92 *pll_ref_freq = *osc_freq / pll_ref_div;
93
94 return 0;
95}
96
97void __init tegra_fixed_clk_init(struct tegra_clk *tegra_clks)
98{
99 struct clk *clk;
100 struct clk **dt_clk;
101
102 /* clk_32k */
103 dt_clk = tegra_lookup_dt_id(clk_id: tegra_clk_clk_32k, tegra_clk: tegra_clks);
104 if (dt_clk) {
105 clk = clk_register_fixed_rate(NULL, name: "clk_32k", NULL, flags: 0, fixed_rate: 32768);
106 *dt_clk = clk;
107 }
108}
109
110void tegra_clk_osc_resume(void __iomem *clk_base)
111{
112 u32 val;
113
114 val = readl_relaxed(clk_base + OSC_CTRL) & ~OSC_CTRL_MASK;
115 val |= osc_ctrl_ctx;
116 writel_relaxed(val, clk_base + OSC_CTRL);
117 fence_udelay(2, clk_base);
118}
119

source code of linux/drivers/clk/tegra/clk-tegra-fixed.c