xref: /openbmc/linux/drivers/clk/meson/vid-pll-div.c (revision ccb01374)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018 BayLibre, SAS.
4  * Author: Neil Armstrong <narmstrong@baylibre.com>
5  */
6 
7 #include <linux/clk-provider.h>
8 #include "clkc.h"
9 
10 static inline struct meson_vid_pll_div_data *
11 meson_vid_pll_div_data(struct clk_regmap *clk)
12 {
13 	return (struct meson_vid_pll_div_data *)clk->data;
14 }
15 
16 /*
17  * This vid_pll divided is a fully programmable fractionnal divider to
18  * achieve complex video clock rates.
19  *
20  * Here are provided the commonly used fraction values provided by Amlogic.
21  */
22 
23 struct vid_pll_div {
24 	unsigned int shift_val;
25 	unsigned int shift_sel;
26 	unsigned int divider;
27 	unsigned int multiplier;
28 };
29 
30 #define VID_PLL_DIV(_val, _sel, _ft, _fb)				\
31 	{								\
32 		.shift_val = (_val),					\
33 		.shift_sel = (_sel),					\
34 		.divider = (_ft),					\
35 		.multiplier = (_fb),					\
36 	}
37 
38 static const struct vid_pll_div vid_pll_div_table[] = {
39 	VID_PLL_DIV(0x0aaa, 0, 2, 1),	/* 2/1  => /2 */
40 	VID_PLL_DIV(0x5294, 2, 5, 2),	/* 5/2  => /2.5 */
41 	VID_PLL_DIV(0x0db6, 0, 3, 1),	/* 3/1  => /3 */
42 	VID_PLL_DIV(0x36cc, 1, 7, 2),	/* 7/2  => /3.5 */
43 	VID_PLL_DIV(0x6666, 2, 15, 4),	/* 15/4 => /3.75 */
44 	VID_PLL_DIV(0x0ccc, 0, 4, 1),	/* 4/1  => /4 */
45 	VID_PLL_DIV(0x739c, 2, 5, 1),	/* 5/1  => /5 */
46 	VID_PLL_DIV(0x0e38, 0, 6, 1),	/* 6/1  => /6 */
47 	VID_PLL_DIV(0x0000, 3, 25, 4),	/* 25/4 => /6.25 */
48 	VID_PLL_DIV(0x3c78, 1, 7, 1),	/* 7/1  => /7 */
49 	VID_PLL_DIV(0x78f0, 2, 15, 2),	/* 15/2 => /7.5 */
50 	VID_PLL_DIV(0x0fc0, 0, 12, 1),	/* 12/1 => /12 */
51 	VID_PLL_DIV(0x3f80, 1, 14, 1),	/* 14/1 => /14 */
52 	VID_PLL_DIV(0x7f80, 2, 15, 1),	/* 15/1 => /15 */
53 };
54 
55 #define to_meson_vid_pll_div(_hw) \
56 	container_of(_hw, struct meson_vid_pll_div, hw)
57 
58 static const struct vid_pll_div *_get_table_val(unsigned int shift_val,
59 						unsigned int shift_sel)
60 {
61 	int i;
62 
63 	for (i = 0 ; i < ARRAY_SIZE(vid_pll_div_table) ; ++i) {
64 		if (vid_pll_div_table[i].shift_val == shift_val &&
65 		    vid_pll_div_table[i].shift_sel == shift_sel)
66 			return &vid_pll_div_table[i];
67 	}
68 
69 	return NULL;
70 }
71 
72 static unsigned long meson_vid_pll_div_recalc_rate(struct clk_hw *hw,
73 						   unsigned long parent_rate)
74 {
75 	struct clk_regmap *clk = to_clk_regmap(hw);
76 	struct meson_vid_pll_div_data *pll_div = meson_vid_pll_div_data(clk);
77 	const struct vid_pll_div *div;
78 
79 	div = _get_table_val(meson_parm_read(clk->map, &pll_div->val),
80 			     meson_parm_read(clk->map, &pll_div->sel));
81 	if (!div || !div->divider) {
82 		pr_info("%s: Invalid config value for vid_pll_div\n", __func__);
83 		return parent_rate;
84 	}
85 
86 	return DIV_ROUND_UP_ULL(parent_rate * div->multiplier, div->divider);
87 }
88 
89 const struct clk_ops meson_vid_pll_div_ro_ops = {
90 	.recalc_rate	= meson_vid_pll_div_recalc_rate,
91 };
92