xref: /openbmc/u-boot/arch/mips/mach-mscc/phy.c (revision f83ef0da)
1 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
2 /*
3  * Copyright (c) 2018 Microsemi Corporation
4  */
5 
6 #include <common.h>
7 #include <asm/io.h>
8 
9 int mscc_phy_rd_wr(u8 read,
10 		   u32 miimdev,
11 		   u8 miim_addr,
12 		   u8 addr,
13 		   u16 *value)
14 {
15 	u32 data;
16 	int i;
17 
18 	/* Command part */
19 	data = (read ? MSCC_F_MII_CMD_MIIM_CMD_OPR_FIELD(2) : /* Read */
20 		MSCC_F_MII_CMD_MIIM_CMD_OPR_FIELD(1) | /* Write */
21 		MSCC_F_MII_CMD_MIIM_CMD_WRDATA(*value)); /* value */
22 
23 	/* Addressing part */
24 	data |=
25 		MSCC_F_MII_CMD_MIIM_CMD_VLD(1) | /* Valid command */
26 		MSCC_F_MII_CMD_MIIM_CMD_REGAD(addr) | /* Reg addr */
27 		MSCC_F_MII_CMD_MIIM_CMD_PHYAD(miim_addr); /* Miim addr */
28 
29 	/* Enqueue MIIM operation to be executed */
30 	writel(data, BASE_DEVCPU_GCB + MIIM_MII_CMD(miimdev));
31 
32 	/* Wait for MIIM operation to finish */
33 	i = 0;
34 	do {
35 		if (i++ > 100) {
36 			debug("Miim timeout");
37 			return -1;
38 		}
39 		data = readl(BASE_DEVCPU_GCB + MIIM_MII_STATUS(miimdev));
40 		debug("Read status miim(%d): 0x%08x\n", miimdev, data);
41 	} while (data & MSCC_F_MII_STATUS_MIIM_STAT_BUSY(1));
42 
43 	if (read) {
44 		data = readl(BASE_DEVCPU_GCB + MIIM_MII_DATA(miimdev));
45 		if (data & MSCC_M_MII_DATA_MIIM_DATA_SUCCESS) {
46 			debug("Read(%d, %d) returned 0x%08x\n",
47 			      miim_addr, addr, data);
48 			return -1;
49 		}
50 		*value = MSCC_X_MII_DATA_MIIM_DATA_RDDATA(data);
51 	}
52 
53 	return 0;
54 }
55 
56 int mscc_phy_rd(u32 miimdev,
57 		u8 miim_addr,
58 		u8 addr,
59 		u16 *value)
60 {
61 	if (mscc_phy_rd_wr(1, miimdev, miim_addr, addr, value) == 0)
62 		return 0;
63 	debug("Read(%d, %d) returned error\n", miim_addr, addr);
64 	return -1;
65 }
66 
67 int mscc_phy_wr(u32 miimdev,
68 		u8 miim_addr,
69 		u8 addr,
70 		u16 value)
71 {
72 	return mscc_phy_rd_wr(0, miimdev, miim_addr, addr, &value);
73 }
74