xref: /openbmc/u-boot/board/gdsys/common/ihs_mdio.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2014
4  * Dirk Eibach,  Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc
5  */
6 
7 #include <common.h>
8 
9 #include <miiphy.h>
10 #ifdef CONFIG_GDSYS_LEGACY_DRIVERS
11 #include <gdsys_fpga.h>
12 #else
13 #include <fdtdec.h>
14 #include <regmap.h>
15 #endif
16 
17 #include "ihs_mdio.h"
18 
19 #ifndef CONFIG_GDSYS_LEGACY_DRIVERS
20 enum {
21 	REG_MDIO_CONTROL = 0x0,
22 	REG_MDIO_ADDR_DATA = 0x2,
23 	REG_MDIO_RX_DATA = 0x4,
24 };
25 
26 static inline u16 read_reg(struct udevice *fpga, uint base, uint addr)
27 {
28 	struct regmap *map;
29 	u8 *ptr;
30 
31 	regmap_init_mem(fpga, &map);
32 	ptr = regmap_get_range(map, 0);
33 
34 	return in_le16((u16 *)(ptr + base + addr));
35 }
36 
37 static inline void write_reg(struct udevice *fpga, uint base, uint addr,
38 			     u16 val)
39 {
40 	struct regmap *map;
41 	u8 *ptr;
42 
43 	regmap_init_mem(fpga, &map);
44 	ptr = regmap_get_range(map, 0);
45 
46 	out_le16((u16 *)(ptr + base + addr), val);
47 }
48 #endif
49 
50 static inline u16 read_control(struct ihs_mdio_info *info)
51 {
52 	u16 val;
53 #ifdef CONFIG_GDSYS_LEGACY_DRIVERS
54 	FPGA_GET_REG(info->fpga, mdio.control, &val);
55 #else
56 	val = read_reg(info->fpga, info->base, REG_MDIO_CONTROL);
57 #endif
58 	return val;
59 }
60 
61 static inline void write_control(struct ihs_mdio_info *info, u16 val)
62 {
63 #ifdef CONFIG_GDSYS_LEGACY_DRIVERS
64 	FPGA_SET_REG(info->fpga, mdio.control, val);
65 #else
66 	write_reg(info->fpga, info->base, REG_MDIO_CONTROL, val);
67 #endif
68 }
69 
70 static inline void write_addr_data(struct ihs_mdio_info *info, u16 val)
71 {
72 #ifdef CONFIG_GDSYS_LEGACY_DRIVERS
73 	FPGA_SET_REG(info->fpga, mdio.address_data, val);
74 #else
75 	write_reg(info->fpga, info->base, REG_MDIO_ADDR_DATA, val);
76 #endif
77 }
78 
79 static inline u16 read_rx_data(struct ihs_mdio_info *info)
80 {
81 	u16 val;
82 #ifdef CONFIG_GDSYS_LEGACY_DRIVERS
83 	FPGA_GET_REG(info->fpga, mdio.rx_data, &val);
84 #else
85 	val = read_reg(info->fpga, info->base, REG_MDIO_RX_DATA);
86 #endif
87 	return val;
88 }
89 
90 static int ihs_mdio_idle(struct mii_dev *bus)
91 {
92 	struct ihs_mdio_info *info = bus->priv;
93 	u16 val;
94 	unsigned int ctr = 0;
95 
96 	do {
97 		val = read_control(info);
98 		udelay(100);
99 		if (ctr++ > 10)
100 			return -1;
101 	} while (!(val & (1 << 12)));
102 
103 	return 0;
104 }
105 
106 static int ihs_mdio_reset(struct mii_dev *bus)
107 {
108 	ihs_mdio_idle(bus);
109 
110 	return 0;
111 }
112 
113 static int ihs_mdio_read(struct mii_dev *bus, int addr, int dev_addr,
114 			 int regnum)
115 {
116 	struct ihs_mdio_info *info = bus->priv;
117 	u16 val;
118 
119 	ihs_mdio_idle(bus);
120 
121 	write_control(info,
122 		      ((addr & 0x1f) << 5) | (regnum & 0x1f) | (2 << 10));
123 
124 	/* wait for rx data available */
125 	udelay(100);
126 
127 	val = read_rx_data(info);
128 
129 	return val;
130 }
131 
132 static int ihs_mdio_write(struct mii_dev *bus, int addr, int dev_addr,
133 			  int regnum, u16 value)
134 {
135 	struct ihs_mdio_info *info = bus->priv;
136 
137 	ihs_mdio_idle(bus);
138 
139 	write_addr_data(info, value);
140 	write_control(info, ((addr & 0x1f) << 5) | (regnum & 0x1f) | (1 << 10));
141 
142 	return 0;
143 }
144 
145 int ihs_mdio_init(struct ihs_mdio_info *info)
146 {
147 	struct mii_dev *bus = mdio_alloc();
148 
149 	if (!bus) {
150 		printf("Failed to allocate FSL MDIO bus\n");
151 		return -1;
152 	}
153 
154 	bus->read = ihs_mdio_read;
155 	bus->write = ihs_mdio_write;
156 	bus->reset = ihs_mdio_reset;
157 	strcpy(bus->name, info->name);
158 
159 	bus->priv = info;
160 
161 	return mdio_register(bus);
162 }
163