1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2017, Intel Corporation
4 */
5 #include <linux/clk-provider.h>
6 #include <linux/slab.h>
7 #include "stratix10-clk.h"
8 #include "clk.h"
9
10 #define SOCFPGA_CS_PDBG_CLK "cs_pdbg_clk"
11 #define to_socfpga_gate_clk(p) container_of(p, struct socfpga_gate_clk, hw.hw)
12
socfpga_gate_clk_recalc_rate(struct clk_hw * hwclk,unsigned long parent_rate)13 static unsigned long socfpga_gate_clk_recalc_rate(struct clk_hw *hwclk,
14 unsigned long parent_rate)
15 {
16 struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
17 u32 div = 1, val;
18
19 if (socfpgaclk->fixed_div) {
20 div = socfpgaclk->fixed_div;
21 } else if (socfpgaclk->div_reg) {
22 val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift;
23 val &= GENMASK(socfpgaclk->width - 1, 0);
24 div = (1 << val);
25 }
26 return parent_rate / div;
27 }
28
socfpga_dbg_clk_recalc_rate(struct clk_hw * hwclk,unsigned long parent_rate)29 static unsigned long socfpga_dbg_clk_recalc_rate(struct clk_hw *hwclk,
30 unsigned long parent_rate)
31 {
32 struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
33 u32 div = 1, val;
34
35 val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift;
36 val &= GENMASK(socfpgaclk->width - 1, 0);
37 div = (1 << val);
38 div = div ? 4 : 1;
39
40 return parent_rate / div;
41 }
42
socfpga_gate_get_parent(struct clk_hw * hwclk)43 static u8 socfpga_gate_get_parent(struct clk_hw *hwclk)
44 {
45 struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
46 u32 mask;
47 u8 parent = 0;
48
49 if (socfpgaclk->bypass_reg) {
50 mask = (0x1 << socfpgaclk->bypass_shift);
51 parent = ((readl(socfpgaclk->bypass_reg) & mask) >>
52 socfpgaclk->bypass_shift);
53 }
54 return parent;
55 }
56
57 static struct clk_ops gateclk_ops = {
58 .recalc_rate = socfpga_gate_clk_recalc_rate,
59 .get_parent = socfpga_gate_get_parent,
60 };
61
62 static const struct clk_ops dbgclk_ops = {
63 .recalc_rate = socfpga_dbg_clk_recalc_rate,
64 .get_parent = socfpga_gate_get_parent,
65 };
66
s10_register_gate(const char * name,const char * parent_name,const char * const * parent_names,u8 num_parents,unsigned long flags,void __iomem * regbase,unsigned long gate_reg,unsigned long gate_idx,unsigned long div_reg,unsigned long div_offset,u8 div_width,unsigned long bypass_reg,u8 bypass_shift,u8 fixed_div)67 struct clk *s10_register_gate(const char *name, const char *parent_name,
68 const char * const *parent_names,
69 u8 num_parents, unsigned long flags,
70 void __iomem *regbase, unsigned long gate_reg,
71 unsigned long gate_idx, unsigned long div_reg,
72 unsigned long div_offset, u8 div_width,
73 unsigned long bypass_reg, u8 bypass_shift,
74 u8 fixed_div)
75 {
76 struct clk *clk;
77 struct socfpga_gate_clk *socfpga_clk;
78 struct clk_init_data init;
79
80 socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
81 if (!socfpga_clk)
82 return NULL;
83
84 socfpga_clk->hw.reg = regbase + gate_reg;
85 socfpga_clk->hw.bit_idx = gate_idx;
86
87 gateclk_ops.enable = clk_gate_ops.enable;
88 gateclk_ops.disable = clk_gate_ops.disable;
89
90 socfpga_clk->fixed_div = fixed_div;
91
92 if (div_reg)
93 socfpga_clk->div_reg = regbase + div_reg;
94 else
95 socfpga_clk->div_reg = NULL;
96
97 socfpga_clk->width = div_width;
98 socfpga_clk->shift = div_offset;
99
100 if (bypass_reg)
101 socfpga_clk->bypass_reg = regbase + bypass_reg;
102 else
103 socfpga_clk->bypass_reg = NULL;
104 socfpga_clk->bypass_shift = bypass_shift;
105
106 if (streq(name, "cs_pdbg_clk"))
107 init.ops = &dbgclk_ops;
108 else
109 init.ops = &gateclk_ops;
110
111 init.name = name;
112 init.flags = flags;
113
114 init.num_parents = num_parents;
115 init.parent_names = parent_names ? parent_names : &parent_name;
116 socfpga_clk->hw.hw.init = &init;
117
118 clk = clk_register(NULL, &socfpga_clk->hw.hw);
119 if (WARN_ON(IS_ERR(clk))) {
120 kfree(socfpga_clk);
121 return NULL;
122 }
123
124 return clk;
125 }
126