1 /*
2 * Copyright (C) 2014 Red Hat
3 * Author: Rob Clark <robdclark@gmail.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program. If not, see <http://www.gnu.org/licenses/>.
16 */
17
18 #include <linux/clk.h>
19 #include <linux/clk-provider.h>
20
21 #include "mdp4_kms.h"
22
23 struct mdp4_lvds_pll {
24 struct clk_hw pll_hw;
25 struct drm_device *dev;
26 unsigned long pixclk;
27 };
28 #define to_mdp4_lvds_pll(x) container_of(x, struct mdp4_lvds_pll, pll_hw)
29
get_kms(struct mdp4_lvds_pll * lvds_pll)30 static struct mdp4_kms *get_kms(struct mdp4_lvds_pll *lvds_pll)
31 {
32 struct msm_drm_private *priv = lvds_pll->dev->dev_private;
33 return to_mdp4_kms(to_mdp_kms(priv->kms));
34 }
35
36 struct pll_rate {
37 unsigned long rate;
38 struct {
39 uint32_t val;
40 uint32_t reg;
41 } conf[32];
42 };
43
44 /* NOTE: keep sorted highest freq to lowest: */
45 static const struct pll_rate freqtbl[] = {
46 { 72000000, {
47 { 0x8f, REG_MDP4_LVDS_PHY_PLL_CTRL_1 },
48 { 0x30, REG_MDP4_LVDS_PHY_PLL_CTRL_2 },
49 { 0xc6, REG_MDP4_LVDS_PHY_PLL_CTRL_3 },
50 { 0x10, REG_MDP4_LVDS_PHY_PLL_CTRL_5 },
51 { 0x07, REG_MDP4_LVDS_PHY_PLL_CTRL_6 },
52 { 0x62, REG_MDP4_LVDS_PHY_PLL_CTRL_7 },
53 { 0x41, REG_MDP4_LVDS_PHY_PLL_CTRL_8 },
54 { 0x0d, REG_MDP4_LVDS_PHY_PLL_CTRL_9 },
55 { 0, 0 } }
56 },
57 };
58
find_rate(unsigned long rate)59 static const struct pll_rate *find_rate(unsigned long rate)
60 {
61 int i;
62 for (i = 1; i < ARRAY_SIZE(freqtbl); i++)
63 if (rate > freqtbl[i].rate)
64 return &freqtbl[i-1];
65 return &freqtbl[i-1];
66 }
67
mpd4_lvds_pll_enable(struct clk_hw * hw)68 static int mpd4_lvds_pll_enable(struct clk_hw *hw)
69 {
70 struct mdp4_lvds_pll *lvds_pll = to_mdp4_lvds_pll(hw);
71 struct mdp4_kms *mdp4_kms = get_kms(lvds_pll);
72 const struct pll_rate *pll_rate = find_rate(lvds_pll->pixclk);
73 int i;
74
75 DBG("pixclk=%lu (%lu)", lvds_pll->pixclk, pll_rate->rate);
76
77 if (WARN_ON(!pll_rate))
78 return -EINVAL;
79
80 mdp4_write(mdp4_kms, REG_MDP4_LCDC_LVDS_PHY_RESET, 0x33);
81
82 for (i = 0; pll_rate->conf[i].reg; i++)
83 mdp4_write(mdp4_kms, pll_rate->conf[i].reg, pll_rate->conf[i].val);
84
85 mdp4_write(mdp4_kms, REG_MDP4_LVDS_PHY_PLL_CTRL_0, 0x01);
86
87 /* Wait until LVDS PLL is locked and ready */
88 while (!mdp4_read(mdp4_kms, REG_MDP4_LVDS_PHY_PLL_LOCKED))
89 cpu_relax();
90
91 return 0;
92 }
93
mpd4_lvds_pll_disable(struct clk_hw * hw)94 static void mpd4_lvds_pll_disable(struct clk_hw *hw)
95 {
96 struct mdp4_lvds_pll *lvds_pll = to_mdp4_lvds_pll(hw);
97 struct mdp4_kms *mdp4_kms = get_kms(lvds_pll);
98
99 DBG("");
100
101 mdp4_write(mdp4_kms, REG_MDP4_LVDS_PHY_CFG0, 0x0);
102 mdp4_write(mdp4_kms, REG_MDP4_LVDS_PHY_PLL_CTRL_0, 0x0);
103 }
104
mpd4_lvds_pll_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)105 static unsigned long mpd4_lvds_pll_recalc_rate(struct clk_hw *hw,
106 unsigned long parent_rate)
107 {
108 struct mdp4_lvds_pll *lvds_pll = to_mdp4_lvds_pll(hw);
109 return lvds_pll->pixclk;
110 }
111
mpd4_lvds_pll_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * parent_rate)112 static long mpd4_lvds_pll_round_rate(struct clk_hw *hw, unsigned long rate,
113 unsigned long *parent_rate)
114 {
115 const struct pll_rate *pll_rate = find_rate(rate);
116 return pll_rate->rate;
117 }
118
mpd4_lvds_pll_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)119 static int mpd4_lvds_pll_set_rate(struct clk_hw *hw, unsigned long rate,
120 unsigned long parent_rate)
121 {
122 struct mdp4_lvds_pll *lvds_pll = to_mdp4_lvds_pll(hw);
123 lvds_pll->pixclk = rate;
124 return 0;
125 }
126
127
128 static const struct clk_ops mpd4_lvds_pll_ops = {
129 .enable = mpd4_lvds_pll_enable,
130 .disable = mpd4_lvds_pll_disable,
131 .recalc_rate = mpd4_lvds_pll_recalc_rate,
132 .round_rate = mpd4_lvds_pll_round_rate,
133 .set_rate = mpd4_lvds_pll_set_rate,
134 };
135
136 static const char *mpd4_lvds_pll_parents[] = {
137 "pxo",
138 };
139
140 static struct clk_init_data pll_init = {
141 .name = "mpd4_lvds_pll",
142 .ops = &mpd4_lvds_pll_ops,
143 .parent_names = mpd4_lvds_pll_parents,
144 .num_parents = ARRAY_SIZE(mpd4_lvds_pll_parents),
145 };
146
mpd4_lvds_pll_init(struct drm_device * dev)147 struct clk *mpd4_lvds_pll_init(struct drm_device *dev)
148 {
149 struct mdp4_lvds_pll *lvds_pll;
150 struct clk *clk;
151 int ret;
152
153 lvds_pll = devm_kzalloc(dev->dev, sizeof(*lvds_pll), GFP_KERNEL);
154 if (!lvds_pll) {
155 ret = -ENOMEM;
156 goto fail;
157 }
158
159 lvds_pll->dev = dev;
160
161 lvds_pll->pll_hw.init = &pll_init;
162 clk = devm_clk_register(dev->dev, &lvds_pll->pll_hw);
163 if (IS_ERR(clk)) {
164 ret = PTR_ERR(clk);
165 goto fail;
166 }
167
168 return clk;
169
170 fail:
171 return ERR_PTR(ret);
172 }
173