1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SGMI module initialisation
4 *
5 * Copyright (C) 2014 Texas Instruments Incorporated
6 * Authors: Sandeep Nair <sandeep_n@ti.com>
7 * Sandeep Paulraj <s-paulraj@ti.com>
8 * Wingman Kwok <w-kwok2@ti.com>
9 *
10 */
11
12#include "netcp.h"
13
14#define SGMII_SRESET_RESET BIT(0)
15#define SGMII_SRESET_RTRESET BIT(1)
16
17#define SGMII_REG_STATUS_LOCK BIT(4)
18#define SGMII_REG_STATUS_LINK BIT(0)
19#define SGMII_REG_STATUS_AUTONEG BIT(2)
20#define SGMII_REG_CONTROL_AUTONEG BIT(0)
21
22#define SGMII23_OFFSET(x) ((x - 2) * 0x100)
23#define SGMII_OFFSET(x) ((x <= 1) ? (x * 0x100) : (SGMII23_OFFSET(x)))
24
25/* SGMII registers */
26#define SGMII_SRESET_REG(x) (SGMII_OFFSET(x) + 0x004)
27#define SGMII_CTL_REG(x) (SGMII_OFFSET(x) + 0x010)
28#define SGMII_STATUS_REG(x) (SGMII_OFFSET(x) + 0x014)
29#define SGMII_MRADV_REG(x) (SGMII_OFFSET(x) + 0x018)
30
31static void sgmii_write_reg(void __iomem *base, int reg, u32 val)
32{
33 writel(val, addr: base + reg);
34}
35
36static u32 sgmii_read_reg(void __iomem *base, int reg)
37{
38 return readl(addr: base + reg);
39}
40
41static void sgmii_write_reg_bit(void __iomem *base, int reg, u32 val)
42{
43 writel(val: (readl(addr: base + reg) | val), addr: base + reg);
44}
45
46/* port is 0 based */
47int netcp_sgmii_reset(void __iomem *sgmii_ofs, int port)
48{
49 /* Soft reset */
50 sgmii_write_reg_bit(base: sgmii_ofs, SGMII_SRESET_REG(port),
51 SGMII_SRESET_RESET);
52
53 while ((sgmii_read_reg(base: sgmii_ofs, SGMII_SRESET_REG(port)) &
54 SGMII_SRESET_RESET) != 0x0)
55 ;
56
57 return 0;
58}
59
60/* port is 0 based */
61bool netcp_sgmii_rtreset(void __iomem *sgmii_ofs, int port, bool set)
62{
63 u32 reg;
64 bool oldval;
65
66 /* Initiate a soft reset */
67 reg = sgmii_read_reg(base: sgmii_ofs, SGMII_SRESET_REG(port));
68 oldval = (reg & SGMII_SRESET_RTRESET) != 0x0;
69 if (set)
70 reg |= SGMII_SRESET_RTRESET;
71 else
72 reg &= ~SGMII_SRESET_RTRESET;
73 sgmii_write_reg(base: sgmii_ofs, SGMII_SRESET_REG(port), val: reg);
74 wmb();
75
76 return oldval;
77}
78
79int netcp_sgmii_get_port_link(void __iomem *sgmii_ofs, int port)
80{
81 u32 status = 0, link = 0;
82
83 status = sgmii_read_reg(base: sgmii_ofs, SGMII_STATUS_REG(port));
84 if ((status & SGMII_REG_STATUS_LINK) != 0)
85 link = 1;
86 return link;
87}
88
89int netcp_sgmii_config(void __iomem *sgmii_ofs, int port, u32 interface)
90{
91 unsigned int i, status, mask;
92 u32 mr_adv_ability;
93 u32 control;
94
95 switch (interface) {
96 case SGMII_LINK_MAC_MAC_AUTONEG:
97 mr_adv_ability = 0x9801;
98 control = 0x21;
99 break;
100
101 case SGMII_LINK_MAC_PHY:
102 case SGMII_LINK_MAC_PHY_NO_MDIO:
103 mr_adv_ability = 1;
104 control = 1;
105 break;
106
107 case SGMII_LINK_MAC_MAC_FORCED:
108 mr_adv_ability = 0x9801;
109 control = 0x20;
110 break;
111
112 case SGMII_LINK_MAC_FIBER:
113 mr_adv_ability = 0x20;
114 control = 0x1;
115 break;
116
117 default:
118 WARN_ONCE(1, "Invalid sgmii interface: %d\n", interface);
119 return -EINVAL;
120 }
121
122 sgmii_write_reg(base: sgmii_ofs, SGMII_CTL_REG(port), val: 0);
123
124 /* Wait for the SerDes pll to lock */
125 for (i = 0; i < 1000; i++) {
126 usleep_range(min: 1000, max: 2000);
127 status = sgmii_read_reg(base: sgmii_ofs, SGMII_STATUS_REG(port));
128 if ((status & SGMII_REG_STATUS_LOCK) != 0)
129 break;
130 }
131
132 if ((status & SGMII_REG_STATUS_LOCK) == 0)
133 pr_err("serdes PLL not locked\n");
134
135 sgmii_write_reg(base: sgmii_ofs, SGMII_MRADV_REG(port), val: mr_adv_ability);
136 sgmii_write_reg(base: sgmii_ofs, SGMII_CTL_REG(port), val: control);
137
138 mask = SGMII_REG_STATUS_LINK;
139 if (control & SGMII_REG_CONTROL_AUTONEG)
140 mask |= SGMII_REG_STATUS_AUTONEG;
141
142 for (i = 0; i < 1000; i++) {
143 usleep_range(min: 200, max: 500);
144 status = sgmii_read_reg(base: sgmii_ofs, SGMII_STATUS_REG(port));
145 if ((status & mask) == mask)
146 break;
147 }
148
149 return 0;
150}
151

source code of linux/drivers/net/ethernet/ti/netcp_sgmii.c