1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) 2016 Rockchip Electronics Co. Ltd.
4 * Author: Lin Huang <hl@rock-chips.com>
5 */
6
7#include <linux/arm-smccc.h>
8#include <linux/clk.h>
9#include <linux/clk-provider.h>
10#include <linux/io.h>
11#include <linux/slab.h>
12#include <soc/rockchip/rockchip_sip.h>
13#include "clk.h"
14
15struct rockchip_ddrclk {
16 struct clk_hw hw;
17 void __iomem *reg_base;
18 int mux_offset;
19 int mux_shift;
20 int mux_width;
21 int div_shift;
22 int div_width;
23 int ddr_flag;
24 spinlock_t *lock;
25};
26
27#define to_rockchip_ddrclk_hw(hw) container_of(hw, struct rockchip_ddrclk, hw)
28
29static int rockchip_ddrclk_sip_set_rate(struct clk_hw *hw, unsigned long drate,
30 unsigned long prate)
31{
32 struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
33 unsigned long flags;
34 struct arm_smccc_res res;
35
36 spin_lock_irqsave(ddrclk->lock, flags);
37 arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, drate, 0,
38 ROCKCHIP_SIP_CONFIG_DRAM_SET_RATE,
39 0, 0, 0, 0, &res);
40 spin_unlock_irqrestore(lock: ddrclk->lock, flags);
41
42 return res.a0;
43}
44
45static unsigned long
46rockchip_ddrclk_sip_recalc_rate(struct clk_hw *hw,
47 unsigned long parent_rate)
48{
49 struct arm_smccc_res res;
50
51 arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
52 ROCKCHIP_SIP_CONFIG_DRAM_GET_RATE,
53 0, 0, 0, 0, &res);
54
55 return res.a0;
56}
57
58static long rockchip_ddrclk_sip_round_rate(struct clk_hw *hw,
59 unsigned long rate,
60 unsigned long *prate)
61{
62 struct arm_smccc_res res;
63
64 arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, rate, 0,
65 ROCKCHIP_SIP_CONFIG_DRAM_ROUND_RATE,
66 0, 0, 0, 0, &res);
67
68 return res.a0;
69}
70
71static u8 rockchip_ddrclk_get_parent(struct clk_hw *hw)
72{
73 struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
74 u32 val;
75
76 val = readl(addr: ddrclk->reg_base +
77 ddrclk->mux_offset) >> ddrclk->mux_shift;
78 val &= GENMASK(ddrclk->mux_width - 1, 0);
79
80 return val;
81}
82
83static const struct clk_ops rockchip_ddrclk_sip_ops = {
84 .recalc_rate = rockchip_ddrclk_sip_recalc_rate,
85 .set_rate = rockchip_ddrclk_sip_set_rate,
86 .round_rate = rockchip_ddrclk_sip_round_rate,
87 .get_parent = rockchip_ddrclk_get_parent,
88};
89
90struct clk *rockchip_clk_register_ddrclk(const char *name, int flags,
91 const char *const *parent_names,
92 u8 num_parents, int mux_offset,
93 int mux_shift, int mux_width,
94 int div_shift, int div_width,
95 int ddr_flag, void __iomem *reg_base,
96 spinlock_t *lock)
97{
98 struct rockchip_ddrclk *ddrclk;
99 struct clk_init_data init;
100 struct clk *clk;
101
102 ddrclk = kzalloc(size: sizeof(*ddrclk), GFP_KERNEL);
103 if (!ddrclk)
104 return ERR_PTR(error: -ENOMEM);
105
106 init.name = name;
107 init.parent_names = parent_names;
108 init.num_parents = num_parents;
109
110 init.flags = flags;
111 init.flags |= CLK_SET_RATE_NO_REPARENT;
112
113 switch (ddr_flag) {
114 case ROCKCHIP_DDRCLK_SIP:
115 init.ops = &rockchip_ddrclk_sip_ops;
116 break;
117 default:
118 pr_err("%s: unsupported ddrclk type %d\n", __func__, ddr_flag);
119 kfree(objp: ddrclk);
120 return ERR_PTR(error: -EINVAL);
121 }
122
123 ddrclk->reg_base = reg_base;
124 ddrclk->lock = lock;
125 ddrclk->hw.init = &init;
126 ddrclk->mux_offset = mux_offset;
127 ddrclk->mux_shift = mux_shift;
128 ddrclk->mux_width = mux_width;
129 ddrclk->div_shift = div_shift;
130 ddrclk->div_width = div_width;
131 ddrclk->ddr_flag = ddr_flag;
132
133 clk = clk_register(NULL, hw: &ddrclk->hw);
134 if (IS_ERR(ptr: clk))
135 kfree(objp: ddrclk);
136
137 return clk;
138}
139EXPORT_SYMBOL_GPL(rockchip_clk_register_ddrclk);
140

source code of linux/drivers/clk/rockchip/clk-ddr.c