xref: /openbmc/u-boot/board/gdsys/common/dp501.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2012
4  * Dirk Eibach,  Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc
5  */
6 
7 /* Parade Technologies Inc. DP501 DisplayPort DVI/HDMI Transmitter */
8 
9 #include <common.h>
10 #include <asm/io.h>
11 #include <errno.h>
12 #include <i2c.h>
13 
14 #define DP501_I2C_ADDR 0x08
15 
16 #ifdef CONFIG_SYS_DP501_I2C
17 int dp501_i2c[] = CONFIG_SYS_DP501_I2C;
18 #endif
19 
20 #ifdef CONFIG_SYS_DP501_BASE
21 int dp501_base[] = CONFIG_SYS_DP501_BASE;
22 #endif
23 
24 static void dp501_setbits(u8 addr, u8 reg, u8 mask)
25 {
26 	u8 val;
27 
28 	val = i2c_reg_read(addr, reg);
29 	setbits_8(&val, mask);
30 	i2c_reg_write(addr, reg, val);
31 }
32 
33 static void dp501_clrbits(u8 addr, u8 reg, u8 mask)
34 {
35 	u8 val;
36 
37 	val = i2c_reg_read(addr, reg);
38 	clrbits_8(&val, mask);
39 	i2c_reg_write(addr, reg, val);
40 }
41 
42 static int dp501_detect_cable_adapter(u8 addr)
43 {
44 	u8 val = i2c_reg_read(addr, 0x00);
45 
46 	return !(val & 0x04);
47 }
48 
49 static void dp501_link_training(u8 addr)
50 {
51 	u8 val;
52 	u8 link_bw;
53 	u8 max_lane_cnt;
54 	u8 lane_cnt;
55 
56 	val = i2c_reg_read(addr, 0x51);
57 	if (val >= 0x0a)
58 		link_bw = 0x0a;
59 	else
60 		link_bw = 0x06;
61 	if (link_bw != val)
62 		printf("DP sink supports %d Mbps link rate, set to %d Mbps\n",
63 		       val * 270, link_bw * 270);
64 	i2c_reg_write(addr, 0x5d, link_bw); /* set link_bw */
65 	val = i2c_reg_read(addr, 0x52);
66 	max_lane_cnt = val & 0x1f;
67 	if (max_lane_cnt >= 4)
68 		lane_cnt = 4;
69 	else
70 		lane_cnt = max_lane_cnt;
71 	if (lane_cnt != max_lane_cnt)
72 		printf("DP sink supports %d lanes, set to %d lanes\n",
73 		       max_lane_cnt, lane_cnt);
74 	i2c_reg_write(addr, 0x5e, lane_cnt | (val & 0x80)); /* set lane_cnt */
75 	val = i2c_reg_read(addr, 0x53);
76 	i2c_reg_write(addr, 0x5c, val); /* set downspread_ctl */
77 
78 	i2c_reg_write(addr, 0x5f, 0x0d); /* start training */
79 }
80 
81 void dp501_powerup(u8 addr)
82 {
83 	dp501_clrbits(addr, 0x0a, 0x30); /* power on encoder */
84 	dp501_setbits(addr, 0x0a, 0x0e); /* block HDCP and MCCS on I2C bride*/
85 	i2c_reg_write(addr, 0x27, 0x30); /* Hardware auto detect DVO timing */
86 	dp501_setbits(addr, 0x72, 0x80); /* DPCD read enable */
87 	dp501_setbits(addr, 0x30, 0x20); /* RS polynomial select */
88 	i2c_reg_write(addr, 0x71, 0x20); /* Enable Aux burst write */
89 	dp501_setbits(addr, 0x78, 0x30); /* Disable HPD2 IRQ */
90 	dp501_clrbits(addr, 0x2f, 0x40); /* Link FIFO reset selection */
91 	dp501_clrbits(addr, 0x60, 0x20); /* Enable scrambling */
92 
93 #ifdef CONFIG_SYS_DP501_VCAPCTRL0
94 	i2c_reg_write(addr, 0x24, CONFIG_SYS_DP501_VCAPCTRL0);
95 #else
96 	i2c_reg_write(addr, 0x24, 0xc0); /* SDR mode 0, ext. H/VSYNC */
97 #endif
98 
99 #ifdef CONFIG_SYS_DP501_DIFFERENTIAL
100 	i2c_reg_write(addr + 2, 0x24, 0x10); /* clock input differential */
101 	i2c_reg_write(addr + 2, 0x25, 0x04);
102 	i2c_reg_write(addr + 2, 0x26, 0x10);
103 #else
104 	i2c_reg_write(addr + 2, 0x24, 0x02); /* clock input single ended */
105 #endif
106 
107 	i2c_reg_write(addr + 2, 0x1a, 0x04); /* SPDIF input method TTL */
108 
109 	i2c_reg_write(addr + 2, 0x00, 0x18); /* driving strength */
110 	i2c_reg_write(addr + 2, 0x03, 0x06); /* driving strength */
111 	i2c_reg_write(addr, 0x2c, 0x00); /* configure N value */
112 	i2c_reg_write(addr, 0x2d, 0x00); /* configure N value */
113 	i2c_reg_write(addr, 0x2e, 0x0c); /* configure N value */
114 	i2c_reg_write(addr, 0x76, 0xff); /* clear all interrupt */
115 	dp501_setbits(addr, 0x78, 0x03); /* clear all interrupt */
116 	i2c_reg_write(addr, 0x75, 0xf8); /* aux channel reset */
117 	i2c_reg_write(addr, 0x75, 0x00); /* clear aux channel reset */
118 	i2c_reg_write(addr, 0x87, 0x7f); /* set retry counter as 7
119 					    retry interval 400us */
120 
121 	if (dp501_detect_cable_adapter(addr)) {
122 		printf("DVI/HDMI cable adapter detected\n");
123 		i2c_reg_write(addr, 0x5e, 0x04); /* enable 4 channel */
124 		dp501_clrbits(addr, 0x00, 0x08); /* DVI/HDMI HDCP operation */
125 	} else {
126 		printf("no DVI/HDMI cable adapter detected\n");
127 		dp501_setbits(addr, 0x00, 0x08); /* for DP HDCP operation */
128 
129 		dp501_link_training(addr);
130 	}
131 }
132 
133 void dp501_powerdown(u8 addr)
134 {
135 	dp501_setbits(addr, 0x0a, 0x30); /* power down encoder, standby mode */
136 }
137 
138 
139 int dp501_probe(unsigned screen, bool power)
140 {
141 #ifdef CONFIG_SYS_DP501_BASE
142 	uint8_t dp501_addr = dp501_base[screen];
143 #else
144 	uint8_t dp501_addr = DP501_I2C_ADDR;
145 #endif
146 
147 #ifdef CONFIG_SYS_DP501_I2C
148 	i2c_set_bus_num(dp501_i2c[screen]);
149 #endif
150 
151 	if (i2c_probe(dp501_addr))
152 		return -1;
153 
154 	dp501_powerup(dp501_addr);
155 
156 	return 0;
157 }
158