1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright 2012 Freescale Semiconductor, Inc.
4 * Copyright 2012 Linaro Ltd.
7 #include <linux/clk-provider.h>
9 #include <linux/slab.h>
10 #include <linux/err.h>
14 * struct clk_pfd - IMX PFD clock
15 * @clk_hw: clock source
16 * @reg: PFD register address
17 * @idx: the index of PFD encoded in the register
19 * PFD clock found on i.MX6 series. Each register for PFD has 4 clk_pfd
20 * data encoded, and member idx is used to specify the one. And each
21 * register has SET, CLR and TOG registers at offset 0x4 0x8 and 0xc.
29 #define to_clk_pfd(_hw) container_of(_hw, struct clk_pfd, hw)
35 static int clk_pfd_enable(struct clk_hw *hw)
37 struct clk_pfd *pfd = to_clk_pfd(hw);
39 writel_relaxed(1 << ((pfd->idx + 1) * 8 - 1), pfd->reg + CLR);
44 static void clk_pfd_disable(struct clk_hw *hw)
46 struct clk_pfd *pfd = to_clk_pfd(hw);
48 writel_relaxed(1 << ((pfd->idx + 1) * 8 - 1), pfd->reg + SET);
51 static unsigned long clk_pfd_recalc_rate(struct clk_hw *hw,
52 unsigned long parent_rate)
54 struct clk_pfd *pfd = to_clk_pfd(hw);
55 u64 tmp = parent_rate;
56 u8 frac = (readl_relaxed(pfd->reg) >> (pfd->idx * 8)) & 0x3f;
64 static long clk_pfd_round_rate(struct clk_hw *hw, unsigned long rate,
70 tmp = tmp * 18 + rate / 2;
84 static int clk_pfd_set_rate(struct clk_hw *hw, unsigned long rate,
85 unsigned long parent_rate)
87 struct clk_pfd *pfd = to_clk_pfd(hw);
88 u64 tmp = parent_rate;
91 tmp = tmp * 18 + rate / 2;
99 writel_relaxed(0x3f << (pfd->idx * 8), pfd->reg + CLR);
100 writel_relaxed(frac << (pfd->idx * 8), pfd->reg + SET);
105 static int clk_pfd_is_enabled(struct clk_hw *hw)
107 struct clk_pfd *pfd = to_clk_pfd(hw);
109 if (readl_relaxed(pfd->reg) & (1 << ((pfd->idx + 1) * 8 - 1)))
115 static const struct clk_ops clk_pfd_ops = {
116 .enable = clk_pfd_enable,
117 .disable = clk_pfd_disable,
118 .recalc_rate = clk_pfd_recalc_rate,
119 .round_rate = clk_pfd_round_rate,
120 .set_rate = clk_pfd_set_rate,
121 .is_enabled = clk_pfd_is_enabled,
124 struct clk_hw *imx_clk_hw_pfd(const char *name, const char *parent_name,
125 void __iomem *reg, u8 idx)
129 struct clk_init_data init;
132 pfd = kzalloc(sizeof(*pfd), GFP_KERNEL);
134 return ERR_PTR(-ENOMEM);
140 init.ops = &clk_pfd_ops;
142 init.parent_names = &parent_name;
143 init.num_parents = 1;
145 pfd->hw.init = &init;
148 ret = clk_hw_register(NULL, hw);