1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2014 Red Hat
4 * Author: Rob Clark <robdclark@gmail.com>
5 */
6
7#include <linux/clk.h>
8#include <linux/clk-provider.h>
9
10#include "mdp4_kms.h"
11
12struct mdp4_lvds_pll {
13	struct clk_hw pll_hw;
14	struct drm_device *dev;
15	unsigned long pixclk;
16};
17#define to_mdp4_lvds_pll(x) container_of(x, struct mdp4_lvds_pll, pll_hw)
18
19static struct mdp4_kms *get_kms(struct mdp4_lvds_pll *lvds_pll)
20{
21	struct msm_drm_private *priv = lvds_pll->dev->dev_private;
22	return to_mdp4_kms(to_mdp_kms(priv->kms));
23}
24
25struct pll_rate {
26	unsigned long rate;
27	struct {
28		uint32_t val;
29		uint32_t reg;
30	} conf[32];
31};
32
33/* NOTE: keep sorted highest freq to lowest: */
34static const struct pll_rate freqtbl[] = {
35	{ 72000000, {
36		{ 0x8f, REG_MDP4_LVDS_PHY_PLL_CTRL_1 },
37		{ 0x30, REG_MDP4_LVDS_PHY_PLL_CTRL_2 },
38		{ 0xc6, REG_MDP4_LVDS_PHY_PLL_CTRL_3 },
39		{ 0x10, REG_MDP4_LVDS_PHY_PLL_CTRL_5 },
40		{ 0x07, REG_MDP4_LVDS_PHY_PLL_CTRL_6 },
41		{ 0x62, REG_MDP4_LVDS_PHY_PLL_CTRL_7 },
42		{ 0x41, REG_MDP4_LVDS_PHY_PLL_CTRL_8 },
43		{ 0x0d, REG_MDP4_LVDS_PHY_PLL_CTRL_9 },
44		{ 0, 0 } }
45	},
46};
47
48static const struct pll_rate *find_rate(unsigned long rate)
49{
50	int i;
51	for (i = 1; i < ARRAY_SIZE(freqtbl); i++)
52		if (rate > freqtbl[i].rate)
53			return &freqtbl[i-1];
54	return &freqtbl[i-1];
55}
56
57static int mpd4_lvds_pll_enable(struct clk_hw *hw)
58{
59	struct mdp4_lvds_pll *lvds_pll = to_mdp4_lvds_pll(hw);
60	struct mdp4_kms *mdp4_kms = get_kms(lvds_pll);
61	const struct pll_rate *pll_rate = find_rate(lvds_pll->pixclk);
62	int i;
63
64	DBG("pixclk=%lu (%lu)", lvds_pll->pixclk, pll_rate->rate);
65
66	if (WARN_ON(!pll_rate))
67		return -EINVAL;
68
69	mdp4_write(mdp4_kms, REG_MDP4_LCDC_LVDS_PHY_RESET, 0x33);
70
71	for (i = 0; pll_rate->conf[i].reg; i++)
72		mdp4_write(mdp4_kms, pll_rate->conf[i].reg, pll_rate->conf[i].val);
73
74	mdp4_write(mdp4_kms, REG_MDP4_LVDS_PHY_PLL_CTRL_0, 0x01);
75
76	/* Wait until LVDS PLL is locked and ready */
77	while (!mdp4_read(mdp4_kms, REG_MDP4_LVDS_PHY_PLL_LOCKED))
78		cpu_relax();
79
80	return 0;
81}
82
83static void mpd4_lvds_pll_disable(struct clk_hw *hw)
84{
85	struct mdp4_lvds_pll *lvds_pll = to_mdp4_lvds_pll(hw);
86	struct mdp4_kms *mdp4_kms = get_kms(lvds_pll);
87
88	DBG("");
89
90	mdp4_write(mdp4_kms, REG_MDP4_LVDS_PHY_CFG0, 0x0);
91	mdp4_write(mdp4_kms, REG_MDP4_LVDS_PHY_PLL_CTRL_0, 0x0);
92}
93
94static unsigned long mpd4_lvds_pll_recalc_rate(struct clk_hw *hw,
95				unsigned long parent_rate)
96{
97	struct mdp4_lvds_pll *lvds_pll = to_mdp4_lvds_pll(hw);
98	return lvds_pll->pixclk;
99}
100
101static long mpd4_lvds_pll_round_rate(struct clk_hw *hw, unsigned long rate,
102		unsigned long *parent_rate)
103{
104	const struct pll_rate *pll_rate = find_rate(rate);
105	return pll_rate->rate;
106}
107
108static int mpd4_lvds_pll_set_rate(struct clk_hw *hw, unsigned long rate,
109		unsigned long parent_rate)
110{
111	struct mdp4_lvds_pll *lvds_pll = to_mdp4_lvds_pll(hw);
112	lvds_pll->pixclk = rate;
113	return 0;
114}
115
116
117static const struct clk_ops mpd4_lvds_pll_ops = {
118	.enable = mpd4_lvds_pll_enable,
119	.disable = mpd4_lvds_pll_disable,
120	.recalc_rate = mpd4_lvds_pll_recalc_rate,
121	.round_rate = mpd4_lvds_pll_round_rate,
122	.set_rate = mpd4_lvds_pll_set_rate,
123};
124
125static const char *mpd4_lvds_pll_parents[] = {
126	"pxo",
127};
128
129static struct clk_init_data pll_init = {
130	.name = "mpd4_lvds_pll",
131	.ops = &mpd4_lvds_pll_ops,
132	.parent_names = mpd4_lvds_pll_parents,
133	.num_parents = ARRAY_SIZE(mpd4_lvds_pll_parents),
134};
135
136struct clk *mpd4_lvds_pll_init(struct drm_device *dev)
137{
138	struct mdp4_lvds_pll *lvds_pll;
139	struct clk *clk;
140	int ret;
141
142	lvds_pll = devm_kzalloc(dev->dev, sizeof(*lvds_pll), GFP_KERNEL);
143	if (!lvds_pll) {
144		ret = -ENOMEM;
145		goto fail;
146	}
147
148	lvds_pll->dev = dev;
149
150	lvds_pll->pll_hw.init = &pll_init;
151	clk = devm_clk_register(dev->dev, &lvds_pll->pll_hw);
152	if (IS_ERR(clk)) {
153		ret = PTR_ERR(clk);
154		goto fail;
155	}
156
157	return clk;
158
159fail:
160	return ERR_PTR(ret);
161}
162