xref: /openbmc/u-boot/board/gdsys/common/dp501.c (revision 0b304a24)
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 
44 	val = i2c_reg_read(addr, 0x51);
45 	i2c_reg_write(addr, 0x5d, val); /* set link_bw */
46 	val = i2c_reg_read(addr, 0x52);
47 	i2c_reg_write(addr, 0x5e, val); /* set lane_cnt */
48 	val = i2c_reg_read(addr, 0x53);
49 	i2c_reg_write(addr, 0x5c, val); /* set downspread_ctl */
50 
51 	i2c_reg_write(addr, 0x5f, 0x0d); /* start training */
52 }
53 
54 void dp501_powerup(u8 addr)
55 {
56 	dp501_clrbits(addr, 0x0a, 0x30); /* power on encoder */
57 	dp501_setbits(addr, 0x0a, 0x0e); /* block HDCP and MCCS on I2C bride*/
58 	i2c_reg_write(addr, 0x27, 0x30); /* Hardware auto detect DVO timing */
59 	dp501_setbits(addr, 0x72, 0x80); /* DPCD read enable */
60 	dp501_setbits(addr, 0x30, 0x20); /* RS polynomial select */
61 	i2c_reg_write(addr, 0x71, 0x20); /* Enable Aux burst write */
62 	dp501_setbits(addr, 0x78, 0x30); /* Disable HPD2 IRQ */
63 	dp501_clrbits(addr, 0x2f, 0x40); /* Link FIFO reset selection */
64 	dp501_clrbits(addr, 0x60, 0x20); /* Enable scrambling */
65 
66 #ifdef CONFIG_SYS_DP501_VCAPCTRL0
67 	i2c_reg_write(addr, 0x24, CONFIG_SYS_DP501_VCAPCTRL0);
68 #else
69 	i2c_reg_write(addr, 0x24, 0xc0); /* SDR mode 0, ext. H/VSYNC */
70 #endif
71 
72 #ifdef CONFIG_SYS_DP501_DIFFERENTIAL
73 	i2c_reg_write(addr + 2, 0x24, 0x10); /* clock input differential */
74 	i2c_reg_write(addr + 2, 0x25, 0x04);
75 	i2c_reg_write(addr + 2, 0x26, 0x10);
76 #else
77 	i2c_reg_write(addr + 2, 0x24, 0x02); /* clock input single ended */
78 #endif
79 
80 	i2c_reg_write(addr + 2, 0x00, 0x18); /* driving strength */
81 	i2c_reg_write(addr + 2, 0x03, 0x06); /* driving strength */
82 	i2c_reg_write(addr, 0x2c, 0x00); /* configure N value */
83 	i2c_reg_write(addr, 0x2d, 0x00); /* configure N value */
84 	i2c_reg_write(addr, 0x2e, 0x0c); /* configure N value */
85 	i2c_reg_write(addr, 0x76, 0xff); /* clear all interrupt */
86 	dp501_setbits(addr, 0x78, 0x03); /* clear all interrupt */
87 	i2c_reg_write(addr, 0x75, 0xf8); /* aux channel reset */
88 	i2c_reg_write(addr, 0x75, 0x00); /* clear aux channel reset */
89 	i2c_reg_write(addr, 0x87, 0x70); /* set retry counter as 7 */
90 
91 	if (dp501_detect_cable_adapter(addr)) {
92 		printf("DVI/HDMI cable adapter detected\n");
93 		i2c_reg_write(addr, 0x5e, 0x04); /* enable 4 channel */
94 		dp501_clrbits(addr, 0x00, 0x08); /* DVI/HDMI HDCP operation */
95 	} else {
96 		printf("no DVI/HDMI cable adapter detected\n");
97 		dp501_setbits(addr, 0x00, 0x08); /* for DP HDCP operation */
98 
99 		dp501_link_training(addr);
100 	}
101 }
102 
103 void dp501_powerdown(u8 addr)
104 {
105 	dp501_setbits(addr, 0x0a, 0x30); /* power down encoder, standby mode */
106 }
107