xref: /openbmc/u-boot/board/gdsys/common/dp501.c (revision 00a457b2)
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 static void dp501_setbits(u8 addr, u8 reg, u8 mask)
16 {
17 	u8 val;
18 
19 	val = i2c_reg_read(addr, reg);
20 	setbits_8(&val, mask);
21 	i2c_reg_write(addr, reg, val);
22 }
23 
24 static void dp501_clrbits(u8 addr, u8 reg, u8 mask)
25 {
26 	u8 val;
27 
28 	val = i2c_reg_read(addr, reg);
29 	clrbits_8(&val, mask);
30 	i2c_reg_write(addr, reg, val);
31 }
32 
33 static int dp501_detect_cable_adapter(u8 addr)
34 {
35 	u8 val = i2c_reg_read(addr, 0x00);
36 
37 	return !(val & 0x04);
38 }
39 
40 static void dp501_link_training(u8 addr)
41 {
42 	u8 val;
43 	u8 link_bw;
44 	u8 max_lane_cnt;
45 	u8 lane_cnt;
46 
47 	val = i2c_reg_read(addr, 0x51);
48 	if (val >= 0x0a)
49 		link_bw = 0x0a;
50 	else
51 		link_bw = 0x06;
52 	if (link_bw != val)
53 		printf("DP sink supports %d Mbps link rate, set to %d Mbps\n",
54 		       val * 270, link_bw * 270);
55 	i2c_reg_write(addr, 0x5d, link_bw); /* set link_bw */
56 	val = i2c_reg_read(addr, 0x52);
57 	max_lane_cnt = val & 0x1f;
58 	if (max_lane_cnt >= 4)
59 		lane_cnt = 4;
60 	else
61 		lane_cnt = max_lane_cnt;
62 	if (lane_cnt != max_lane_cnt)
63 		printf("DP sink supports %d lanes, set to %d lanes\n",
64 		       max_lane_cnt, lane_cnt);
65 	i2c_reg_write(addr, 0x5e, lane_cnt | (val & 0x80)); /* set lane_cnt */
66 	val = i2c_reg_read(addr, 0x53);
67 	i2c_reg_write(addr, 0x5c, val); /* set downspread_ctl */
68 
69 	i2c_reg_write(addr, 0x5f, 0x0d); /* start training */
70 }
71 
72 void dp501_powerup(u8 addr)
73 {
74 	dp501_clrbits(addr, 0x0a, 0x30); /* power on encoder */
75 	dp501_setbits(addr, 0x0a, 0x0e); /* block HDCP and MCCS on I2C bride*/
76 	i2c_reg_write(addr, 0x27, 0x30); /* Hardware auto detect DVO timing */
77 	dp501_setbits(addr, 0x72, 0x80); /* DPCD read enable */
78 	dp501_setbits(addr, 0x30, 0x20); /* RS polynomial select */
79 	i2c_reg_write(addr, 0x71, 0x20); /* Enable Aux burst write */
80 	dp501_setbits(addr, 0x78, 0x30); /* Disable HPD2 IRQ */
81 	dp501_clrbits(addr, 0x2f, 0x40); /* Link FIFO reset selection */
82 	dp501_clrbits(addr, 0x60, 0x20); /* Enable scrambling */
83 
84 #ifdef CONFIG_SYS_DP501_VCAPCTRL0
85 	i2c_reg_write(addr, 0x24, CONFIG_SYS_DP501_VCAPCTRL0);
86 #else
87 	i2c_reg_write(addr, 0x24, 0xc0); /* SDR mode 0, ext. H/VSYNC */
88 #endif
89 
90 #ifdef CONFIG_SYS_DP501_DIFFERENTIAL
91 	i2c_reg_write(addr + 2, 0x24, 0x10); /* clock input differential */
92 	i2c_reg_write(addr + 2, 0x25, 0x04);
93 	i2c_reg_write(addr + 2, 0x26, 0x10);
94 #else
95 	i2c_reg_write(addr + 2, 0x24, 0x02); /* clock input single ended */
96 #endif
97 
98 	i2c_reg_write(addr + 2, 0x1a, 0x04); /* SPDIF input method TTL */
99 
100 	i2c_reg_write(addr + 2, 0x00, 0x18); /* driving strength */
101 	i2c_reg_write(addr + 2, 0x03, 0x06); /* driving strength */
102 	i2c_reg_write(addr, 0x2c, 0x00); /* configure N value */
103 	i2c_reg_write(addr, 0x2d, 0x00); /* configure N value */
104 	i2c_reg_write(addr, 0x2e, 0x0c); /* configure N value */
105 	i2c_reg_write(addr, 0x76, 0xff); /* clear all interrupt */
106 	dp501_setbits(addr, 0x78, 0x03); /* clear all interrupt */
107 	i2c_reg_write(addr, 0x75, 0xf8); /* aux channel reset */
108 	i2c_reg_write(addr, 0x75, 0x00); /* clear aux channel reset */
109 	i2c_reg_write(addr, 0x87, 0x7f); /* set retry counter as 7
110 					    retry interval 400us */
111 
112 	if (dp501_detect_cable_adapter(addr)) {
113 		printf("DVI/HDMI cable adapter detected\n");
114 		i2c_reg_write(addr, 0x5e, 0x04); /* enable 4 channel */
115 		dp501_clrbits(addr, 0x00, 0x08); /* DVI/HDMI HDCP operation */
116 	} else {
117 		printf("no DVI/HDMI cable adapter detected\n");
118 		dp501_setbits(addr, 0x00, 0x08); /* for DP HDCP operation */
119 
120 		dp501_link_training(addr);
121 	}
122 }
123 
124 void dp501_powerdown(u8 addr)
125 {
126 	dp501_setbits(addr, 0x0a, 0x30); /* power down encoder, standby mode */
127 }
128