xref: /openbmc/u-boot/board/gdsys/common/dp501.c (revision 1d2c0506)
1 /*
2  * (C) Copyright 2012
3  * Dirk Eibach,  Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 /* Parade Technologies Inc. DP501 DisplayPort DVI/HDMI Transmitter */
9 
10 #include <common.h>
11 #include <asm/io.h>
12 #include <errno.h>
13 #include <i2c.h>
14 
15 #define DP501_I2C_ADDR 0x08
16 
17 #ifdef CONFIG_SYS_DP501_I2C
18 int dp501_i2c[] = CONFIG_SYS_DP501_I2C;
19 #endif
20 
21 #ifdef CONFIG_SYS_DP501_BASE
22 int dp501_base[] = CONFIG_SYS_DP501_BASE;
23 #endif
24 
25 static void dp501_setbits(u8 addr, u8 reg, u8 mask)
26 {
27 	u8 val;
28 
29 	val = i2c_reg_read(addr, reg);
30 	setbits_8(&val, mask);
31 	i2c_reg_write(addr, reg, val);
32 }
33 
34 static void dp501_clrbits(u8 addr, u8 reg, u8 mask)
35 {
36 	u8 val;
37 
38 	val = i2c_reg_read(addr, reg);
39 	clrbits_8(&val, mask);
40 	i2c_reg_write(addr, reg, val);
41 }
42 
43 static int dp501_detect_cable_adapter(u8 addr)
44 {
45 	u8 val = i2c_reg_read(addr, 0x00);
46 
47 	return !(val & 0x04);
48 }
49 
50 static void dp501_link_training(u8 addr)
51 {
52 	u8 val;
53 	u8 link_bw;
54 	u8 max_lane_cnt;
55 	u8 lane_cnt;
56 
57 	val = i2c_reg_read(addr, 0x51);
58 	if (val >= 0x0a)
59 		link_bw = 0x0a;
60 	else
61 		link_bw = 0x06;
62 	if (link_bw != val)
63 		printf("DP sink supports %d Mbps link rate, set to %d Mbps\n",
64 		       val * 270, link_bw * 270);
65 	i2c_reg_write(addr, 0x5d, link_bw); /* set link_bw */
66 	val = i2c_reg_read(addr, 0x52);
67 	max_lane_cnt = val & 0x1f;
68 	if (max_lane_cnt >= 4)
69 		lane_cnt = 4;
70 	else
71 		lane_cnt = max_lane_cnt;
72 	if (lane_cnt != max_lane_cnt)
73 		printf("DP sink supports %d lanes, set to %d lanes\n",
74 		       max_lane_cnt, lane_cnt);
75 	i2c_reg_write(addr, 0x5e, lane_cnt | (val & 0x80)); /* set lane_cnt */
76 	val = i2c_reg_read(addr, 0x53);
77 	i2c_reg_write(addr, 0x5c, val); /* set downspread_ctl */
78 
79 	i2c_reg_write(addr, 0x5f, 0x0d); /* start training */
80 }
81 
82 void dp501_powerup(u8 addr)
83 {
84 	dp501_clrbits(addr, 0x0a, 0x30); /* power on encoder */
85 	dp501_setbits(addr, 0x0a, 0x0e); /* block HDCP and MCCS on I2C bride*/
86 	i2c_reg_write(addr, 0x27, 0x30); /* Hardware auto detect DVO timing */
87 	dp501_setbits(addr, 0x72, 0x80); /* DPCD read enable */
88 	dp501_setbits(addr, 0x30, 0x20); /* RS polynomial select */
89 	i2c_reg_write(addr, 0x71, 0x20); /* Enable Aux burst write */
90 	dp501_setbits(addr, 0x78, 0x30); /* Disable HPD2 IRQ */
91 	dp501_clrbits(addr, 0x2f, 0x40); /* Link FIFO reset selection */
92 	dp501_clrbits(addr, 0x60, 0x20); /* Enable scrambling */
93 
94 #ifdef CONFIG_SYS_DP501_VCAPCTRL0
95 	i2c_reg_write(addr, 0x24, CONFIG_SYS_DP501_VCAPCTRL0);
96 #else
97 	i2c_reg_write(addr, 0x24, 0xc0); /* SDR mode 0, ext. H/VSYNC */
98 #endif
99 
100 #ifdef CONFIG_SYS_DP501_DIFFERENTIAL
101 	i2c_reg_write(addr + 2, 0x24, 0x10); /* clock input differential */
102 	i2c_reg_write(addr + 2, 0x25, 0x04);
103 	i2c_reg_write(addr + 2, 0x26, 0x10);
104 #else
105 	i2c_reg_write(addr + 2, 0x24, 0x02); /* clock input single ended */
106 #endif
107 
108 	i2c_reg_write(addr + 2, 0x1a, 0x04); /* SPDIF input method TTL */
109 
110 	i2c_reg_write(addr + 2, 0x00, 0x18); /* driving strength */
111 	i2c_reg_write(addr + 2, 0x03, 0x06); /* driving strength */
112 	i2c_reg_write(addr, 0x2c, 0x00); /* configure N value */
113 	i2c_reg_write(addr, 0x2d, 0x00); /* configure N value */
114 	i2c_reg_write(addr, 0x2e, 0x0c); /* configure N value */
115 	i2c_reg_write(addr, 0x76, 0xff); /* clear all interrupt */
116 	dp501_setbits(addr, 0x78, 0x03); /* clear all interrupt */
117 	i2c_reg_write(addr, 0x75, 0xf8); /* aux channel reset */
118 	i2c_reg_write(addr, 0x75, 0x00); /* clear aux channel reset */
119 	i2c_reg_write(addr, 0x87, 0x7f); /* set retry counter as 7
120 					    retry interval 400us */
121 
122 	if (dp501_detect_cable_adapter(addr)) {
123 		printf("DVI/HDMI cable adapter detected\n");
124 		i2c_reg_write(addr, 0x5e, 0x04); /* enable 4 channel */
125 		dp501_clrbits(addr, 0x00, 0x08); /* DVI/HDMI HDCP operation */
126 	} else {
127 		printf("no DVI/HDMI cable adapter detected\n");
128 		dp501_setbits(addr, 0x00, 0x08); /* for DP HDCP operation */
129 
130 		dp501_link_training(addr);
131 	}
132 }
133 
134 void dp501_powerdown(u8 addr)
135 {
136 	dp501_setbits(addr, 0x0a, 0x30); /* power down encoder, standby mode */
137 }
138 
139 
140 int dp501_probe(unsigned screen, bool power)
141 {
142 #ifdef CONFIG_SYS_DP501_BASE
143 	uint8_t dp501_addr = dp501_base[screen];
144 #else
145 	uint8_t dp501_addr = DP501_I2C_ADDR;
146 #endif
147 
148 #ifdef CONFIG_SYS_DP501_I2C
149 	i2c_set_bus_num(dp501_i2c[screen]);
150 #endif
151 
152 	if (i2c_probe(dp501_addr))
153 		return -1;
154 
155 	dp501_powerup(dp501_addr);
156 
157 	return 0;
158 }
159