xref: /openbmc/u-boot/drivers/net/fm/memac_phy.c (revision f13606b7)
1 /*
2  * Copyright 2012 Freescale Semiconductor, Inc.
3  *	Andy Fleming <afleming@gmail.com>
4  *	Roy Zang <tie-fei.zang@freescale.com>
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  * Some part is taken from tsec.c
8  */
9 #include <common.h>
10 #include <miiphy.h>
11 #include <phy.h>
12 #include <asm/io.h>
13 #include <asm/fsl_memac.h>
14 #include <fm_eth.h>
15 
16 /*
17  * Write value to the PHY for this device to the register at regnum, waiting
18  * until the write is done before it returns.  All PHY configuration has to be
19  * done through the TSEC1 MIIM regs
20  */
21 int memac_mdio_write(struct mii_dev *bus, int port_addr, int dev_addr,
22 			int regnum, u16 value)
23 {
24 	u32 mdio_ctl;
25 	struct memac_mdio_controller *regs = bus->priv;
26 	u32 c45 = 1; /* Default to 10G interface */
27 
28 	if (dev_addr == MDIO_DEVAD_NONE) {
29 		c45 = 0; /* clause 22 */
30 		dev_addr = regnum & 0x1f;
31 		clrbits_be32(&regs->mdio_stat, MDIO_STAT_ENC);
32 	} else
33 		setbits_be32(&regs->mdio_stat, MDIO_STAT_ENC);
34 
35 	/* Wait till the bus is free */
36 	while ((in_be32(&regs->mdio_stat)) & MDIO_STAT_BSY)
37 		;
38 
39 	/* Set the port and dev addr */
40 	mdio_ctl = MDIO_CTL_PORT_ADDR(port_addr) | MDIO_CTL_DEV_ADDR(dev_addr);
41 	out_be32(&regs->mdio_ctl, mdio_ctl);
42 
43 	/* Set the register address */
44 	if (c45)
45 		out_be32(&regs->mdio_addr, regnum & 0xffff);
46 
47 	/* Wait till the bus is free */
48 	while ((in_be32(&regs->mdio_stat)) & MDIO_STAT_BSY)
49 		;
50 
51 	/* Write the value to the register */
52 	out_be32(&regs->mdio_data, MDIO_DATA(value));
53 
54 	/* Wait till the MDIO write is complete */
55 	while ((in_be32(&regs->mdio_data)) & MDIO_DATA_BSY)
56 		;
57 
58 	return 0;
59 }
60 
61 /*
62  * Reads from register regnum in the PHY for device dev, returning the value.
63  * Clears miimcom first.  All PHY configuration has to be done through the
64  * TSEC1 MIIM regs
65  */
66 int memac_mdio_read(struct mii_dev *bus, int port_addr, int dev_addr,
67 			int regnum)
68 {
69 	u32 mdio_ctl;
70 	struct memac_mdio_controller *regs = bus->priv;
71 	u32 c45 = 1;
72 
73 	if (dev_addr == MDIO_DEVAD_NONE) {
74 		if (!strcmp(bus->name, DEFAULT_FM_TGEC_MDIO_NAME))
75 			return 0xffff;
76 		c45 = 0; /* clause 22 */
77 		dev_addr = regnum & 0x1f;
78 		clrbits_be32(&regs->mdio_stat, MDIO_STAT_ENC);
79 	} else
80 		setbits_be32(&regs->mdio_stat, MDIO_STAT_ENC);
81 
82 	/* Wait till the bus is free */
83 	while ((in_be32(&regs->mdio_stat)) & MDIO_STAT_BSY)
84 		;
85 
86 	/* Set the Port and Device Addrs */
87 	mdio_ctl = MDIO_CTL_PORT_ADDR(port_addr) | MDIO_CTL_DEV_ADDR(dev_addr);
88 	out_be32(&regs->mdio_ctl, mdio_ctl);
89 
90 	/* Set the register address */
91 	if (c45)
92 		out_be32(&regs->mdio_addr, regnum & 0xffff);
93 
94 	/* Wait till the bus is free */
95 	while ((in_be32(&regs->mdio_stat)) & MDIO_STAT_BSY)
96 		;
97 
98 	/* Initiate the read */
99 	mdio_ctl |= MDIO_CTL_READ;
100 	out_be32(&regs->mdio_ctl, mdio_ctl);
101 
102 	/* Wait till the MDIO write is complete */
103 	while ((in_be32(&regs->mdio_data)) & MDIO_DATA_BSY)
104 		;
105 
106 	/* Return all Fs if nothing was there */
107 	if (in_be32(&regs->mdio_stat) & MDIO_STAT_RD_ER)
108 		return 0xffff;
109 
110 	return in_be32(&regs->mdio_data) & 0xffff;
111 }
112 
113 int memac_mdio_reset(struct mii_dev *bus)
114 {
115 	return 0;
116 }
117 
118 int fm_memac_mdio_init(bd_t *bis, struct memac_mdio_info *info)
119 {
120 	struct mii_dev *bus = mdio_alloc();
121 
122 	if (!bus) {
123 		printf("Failed to allocate FM TGEC MDIO bus\n");
124 		return -1;
125 	}
126 
127 	bus->read = memac_mdio_read;
128 	bus->write = memac_mdio_write;
129 	bus->reset = memac_mdio_reset;
130 	sprintf(bus->name, info->name);
131 
132 	bus->priv = info->regs;
133 
134 	/*
135 	 * On some platforms like B4860, default value of MDIO_CLK_DIV bits
136 	 * in mdio_stat(mdio_cfg) register generates MDIO clock too high
137 	 * (much higher than 2.5MHz), violating the IEEE specs.
138 	 * On other platforms like T1040, default value of MDIO_CLK_DIV bits
139 	 * is zero, so MDIO clock is disabled.
140 	 * So, for proper functioning of MDIO, MDIO_CLK_DIV bits needs to
141 	 * be properly initialized.
142 	 * NEG bit default should be '1' as per FMAN-v3 RM, but on platform
143 	 * like T2080QDS, this bit default is '0', which leads to MDIO failure
144 	 * on XAUI PHY, so set this bit definitely.
145 	 */
146 	setbits_be32(&((struct memac_mdio_controller *)info->regs)->mdio_stat,
147 		     MDIO_STAT_CLKDIV(258) | MDIO_STAT_NEG);
148 
149 	return mdio_register(bus);
150 }
151