1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2014 Marvell Technology Group Ltd.
4 *
5 * Alexandre Belloni <alexandre.belloni@free-electrons.com>
6 * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
7 */
8#include <linux/clk-provider.h>
9#include <linux/io.h>
10#include <linux/kernel.h>
11#include <linux/of.h>
12#include <linux/of_address.h>
13#include <linux/slab.h>
14#include <asm/div64.h>
15
16#include "berlin2-div.h"
17#include "berlin2-pll.h"
18
19struct berlin2_pll {
20	struct clk_hw hw;
21	void __iomem *base;
22	struct berlin2_pll_map map;
23};
24
25#define to_berlin2_pll(hw) container_of(hw, struct berlin2_pll, hw)
26
27#define SPLL_CTRL0	0x00
28#define SPLL_CTRL1	0x04
29#define SPLL_CTRL2	0x08
30#define SPLL_CTRL3	0x0c
31#define SPLL_CTRL4	0x10
32
33#define FBDIV_MASK	0x1ff
34#define RFDIV_MASK	0x1f
35#define DIVSEL_MASK	0xf
36
37/*
38 * The output frequency formula for the pll is:
39 * clkout = fbdiv / refdiv * parent / vcodiv
40 */
41static unsigned long
42berlin2_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
43{
44	struct berlin2_pll *pll = to_berlin2_pll(hw);
45	struct berlin2_pll_map *map = &pll->map;
46	u32 val, fbdiv, rfdiv, vcodivsel, vcodiv;
47	u64 rate = parent_rate;
48
49	val = readl_relaxed(pll->base + SPLL_CTRL0);
50	fbdiv = (val >> map->fbdiv_shift) & FBDIV_MASK;
51	rfdiv = (val >> map->rfdiv_shift) & RFDIV_MASK;
52	if (rfdiv == 0) {
53		pr_warn("%s has zero rfdiv\n", clk_hw_get_name(hw));
54		rfdiv = 1;
55	}
56
57	val = readl_relaxed(pll->base + SPLL_CTRL1);
58	vcodivsel = (val >> map->divsel_shift) & DIVSEL_MASK;
59	vcodiv = map->vcodiv[vcodivsel];
60	if (vcodiv == 0) {
61		pr_warn("%s has zero vcodiv (index %d)\n",
62			clk_hw_get_name(hw), vcodivsel);
63		vcodiv = 1;
64	}
65
66	rate *= fbdiv * map->mult;
67	do_div(rate, rfdiv * vcodiv);
68
69	return (unsigned long)rate;
70}
71
72static const struct clk_ops berlin2_pll_ops = {
73	.recalc_rate	= berlin2_pll_recalc_rate,
74};
75
76int __init
77berlin2_pll_register(const struct berlin2_pll_map *map,
78		     void __iomem *base, const char *name,
79		     const char *parent_name, unsigned long flags)
80{
81	struct clk_init_data init;
82	struct berlin2_pll *pll;
83
84	pll = kzalloc(sizeof(*pll), GFP_KERNEL);
85	if (!pll)
86		return -ENOMEM;
87
88	/* copy pll_map to allow __initconst */
89	memcpy(&pll->map, map, sizeof(*map));
90	pll->base = base;
91	pll->hw.init = &init;
92	init.name = name;
93	init.ops = &berlin2_pll_ops;
94	init.parent_names = &parent_name;
95	init.num_parents = 1;
96	init.flags = flags;
97
98	return clk_hw_register(NULL, &pll->hw);
99}
100