1// SPDX-License-Identifier: GPL-2.0
2/* Copyright Sunplus Technology Co., Ltd.
3 * All rights reserved.
4 */
5
6#include <linux/platform_device.h>
7#include <linux/netdevice.h>
8#include <linux/bitfield.h>
9#include <linux/of_mdio.h>
10
11#include "spl2sw_register.h"
12#include "spl2sw_define.h"
13#include "spl2sw_mdio.h"
14
15#define SPL2SW_MDIO_READ_CMD 0x02
16#define SPL2SW_MDIO_WRITE_CMD 0x01
17
18static int spl2sw_mdio_access(struct spl2sw_common *comm, u8 cmd, u8 addr, u8 regnum, u16 wdata)
19{
20 u32 reg, reg2;
21 u32 val;
22 int ret;
23
24 /* Note that addr (of phy) should match either ext_phy0_addr
25 * or ext_phy1_addr, or mdio commands won't be sent out.
26 */
27 reg = readl(addr: comm->l2sw_reg_base + L2SW_MAC_FORCE_MODE);
28 reg &= ~MAC_EXT_PHY0_ADDR;
29 reg |= FIELD_PREP(MAC_EXT_PHY0_ADDR, addr);
30
31 reg2 = FIELD_PREP(MAC_CPU_PHY_WT_DATA, wdata) | FIELD_PREP(MAC_CPU_PHY_CMD, cmd) |
32 FIELD_PREP(MAC_CPU_PHY_REG_ADDR, regnum) | FIELD_PREP(MAC_CPU_PHY_ADDR, addr);
33
34 /* Set ext_phy0_addr and then issue mdio command.
35 * No interrupt is allowed in between.
36 */
37 spin_lock_irq(lock: &comm->mdio_lock);
38 writel(val: reg, addr: comm->l2sw_reg_base + L2SW_MAC_FORCE_MODE);
39 writel(val: reg2, addr: comm->l2sw_reg_base + L2SW_PHY_CNTL_REG0);
40 spin_unlock_irq(lock: &comm->mdio_lock);
41
42 ret = read_poll_timeout(readl, val, val & cmd, 1, 1000, true,
43 comm->l2sw_reg_base + L2SW_PHY_CNTL_REG1);
44
45 /* Set ext_phy0_addr back to 31 to prevent
46 * from sending mdio command to phy by
47 * hardware auto-mdio function.
48 */
49 reg = readl(addr: comm->l2sw_reg_base + L2SW_MAC_FORCE_MODE);
50 reg &= ~MAC_EXT_PHY0_ADDR;
51 reg |= FIELD_PREP(MAC_EXT_PHY0_ADDR, 31);
52 writel(val: reg, addr: comm->l2sw_reg_base + L2SW_MAC_FORCE_MODE);
53
54 if (ret == 0)
55 return val >> 16;
56 else
57 return ret;
58}
59
60static int spl2sw_mii_read(struct mii_bus *bus, int addr, int regnum)
61{
62 struct spl2sw_common *comm = bus->priv;
63
64 return spl2sw_mdio_access(comm, SPL2SW_MDIO_READ_CMD, addr, regnum, wdata: 0);
65}
66
67static int spl2sw_mii_write(struct mii_bus *bus, int addr, int regnum, u16 val)
68{
69 struct spl2sw_common *comm = bus->priv;
70 int ret;
71
72 ret = spl2sw_mdio_access(comm, SPL2SW_MDIO_WRITE_CMD, addr, regnum, wdata: val);
73 if (ret < 0)
74 return ret;
75
76 return 0;
77}
78
79u32 spl2sw_mdio_init(struct spl2sw_common *comm)
80{
81 struct device_node *mdio_np;
82 struct mii_bus *mii_bus;
83 int ret;
84
85 /* Get mdio child node. */
86 mdio_np = of_get_child_by_name(node: comm->pdev->dev.of_node, name: "mdio");
87 if (!mdio_np) {
88 dev_err(&comm->pdev->dev, "No mdio child node found!\n");
89 return -ENODEV;
90 }
91
92 /* Allocate and register mdio bus. */
93 mii_bus = devm_mdiobus_alloc(dev: &comm->pdev->dev);
94 if (!mii_bus) {
95 ret = -ENOMEM;
96 goto out;
97 }
98
99 mii_bus->name = "sunplus_mii_bus";
100 mii_bus->parent = &comm->pdev->dev;
101 mii_bus->priv = comm;
102 mii_bus->read = spl2sw_mii_read;
103 mii_bus->write = spl2sw_mii_write;
104 snprintf(buf: mii_bus->id, MII_BUS_ID_SIZE, fmt: "%s-mii", dev_name(dev: &comm->pdev->dev));
105
106 ret = of_mdiobus_register(mdio: mii_bus, np: mdio_np);
107 if (ret) {
108 dev_err(&comm->pdev->dev, "Failed to register mdiobus!\n");
109 goto out;
110 }
111
112 comm->mii_bus = mii_bus;
113
114out:
115 of_node_put(node: mdio_np);
116 return ret;
117}
118
119void spl2sw_mdio_remove(struct spl2sw_common *comm)
120{
121 if (comm->mii_bus) {
122 mdiobus_unregister(bus: comm->mii_bus);
123 comm->mii_bus = NULL;
124 }
125}
126

source code of linux/drivers/net/ethernet/sunplus/spl2sw_mdio.c