1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Adaptrum Anarion DWMAC glue layer
4  *
5  * Copyright (C) 2017, Adaptrum, Inc.
6  * (Written by Alexandru Gagniuc <alex.g at adaptrum.com> for Adaptrum, Inc.)
7  */
8 
9 #include <linux/io.h>
10 #include <linux/of.h>
11 #include <linux/of_net.h>
12 #include <linux/stmmac.h>
13 
14 #include "stmmac.h"
15 #include "stmmac_platform.h"
16 
17 #define GMAC_RESET_CONTROL_REG		0
18 #define GMAC_SW_CONFIG_REG		4
19 #define  GMAC_CONFIG_INTF_SEL_MASK	(0x7 << 0)
20 #define  GMAC_CONFIG_INTF_RGMII		(0x1 << 0)
21 
22 struct anarion_gmac {
23 	uintptr_t ctl_block;
24 	uint32_t phy_intf_sel;
25 };
26 
27 static uint32_t gmac_read_reg(struct anarion_gmac *gmac, uint8_t reg)
28 {
29 	return readl((void *)(gmac->ctl_block + reg));
30 };
31 
32 static void gmac_write_reg(struct anarion_gmac *gmac, uint8_t reg, uint32_t val)
33 {
34 	writel(val, (void *)(gmac->ctl_block + reg));
35 }
36 
37 static int anarion_gmac_init(struct platform_device *pdev, void *priv)
38 {
39 	uint32_t sw_config;
40 	struct anarion_gmac *gmac = priv;
41 
42 	/* Reset logic, configure interface mode, then release reset. SIMPLE! */
43 	gmac_write_reg(gmac, GMAC_RESET_CONTROL_REG, 1);
44 
45 	sw_config = gmac_read_reg(gmac, GMAC_SW_CONFIG_REG);
46 	sw_config &= ~GMAC_CONFIG_INTF_SEL_MASK;
47 	sw_config |= (gmac->phy_intf_sel & GMAC_CONFIG_INTF_SEL_MASK);
48 	gmac_write_reg(gmac, GMAC_SW_CONFIG_REG, sw_config);
49 
50 	gmac_write_reg(gmac, GMAC_RESET_CONTROL_REG, 0);
51 
52 	return 0;
53 }
54 
55 static void anarion_gmac_exit(struct platform_device *pdev, void *priv)
56 {
57 	struct anarion_gmac *gmac = priv;
58 
59 	gmac_write_reg(gmac, GMAC_RESET_CONTROL_REG, 1);
60 }
61 
62 static struct anarion_gmac *anarion_config_dt(struct platform_device *pdev)
63 {
64 	struct anarion_gmac *gmac;
65 	phy_interface_t phy_mode;
66 	void __iomem *ctl_block;
67 	int err;
68 
69 	ctl_block = devm_platform_ioremap_resource(pdev, 1);
70 	if (IS_ERR(ctl_block)) {
71 		dev_err(&pdev->dev, "Cannot get reset region (%ld)!\n",
72 			PTR_ERR(ctl_block));
73 		return ctl_block;
74 	}
75 
76 	gmac = devm_kzalloc(&pdev->dev, sizeof(*gmac), GFP_KERNEL);
77 	if (!gmac)
78 		return ERR_PTR(-ENOMEM);
79 
80 	gmac->ctl_block = (uintptr_t)ctl_block;
81 
82 	err = of_get_phy_mode(pdev->dev.of_node, &phy_mode);
83 	if (err)
84 		return ERR_PTR(err);
85 
86 	switch (phy_mode) {
87 	case PHY_INTERFACE_MODE_RGMII:
88 		fallthrough;
89 	case PHY_INTERFACE_MODE_RGMII_ID:
90 	case PHY_INTERFACE_MODE_RGMII_RXID:
91 	case PHY_INTERFACE_MODE_RGMII_TXID:
92 		gmac->phy_intf_sel = GMAC_CONFIG_INTF_RGMII;
93 		break;
94 	default:
95 		dev_err(&pdev->dev, "Unsupported phy-mode (%d)\n",
96 			phy_mode);
97 		return ERR_PTR(-ENOTSUPP);
98 	}
99 
100 	return gmac;
101 }
102 
103 static int anarion_dwmac_probe(struct platform_device *pdev)
104 {
105 	int ret;
106 	struct anarion_gmac *gmac;
107 	struct plat_stmmacenet_data *plat_dat;
108 	struct stmmac_resources stmmac_res;
109 
110 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
111 	if (ret)
112 		return ret;
113 
114 	gmac = anarion_config_dt(pdev);
115 	if (IS_ERR(gmac))
116 		return PTR_ERR(gmac);
117 
118 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
119 	if (IS_ERR(plat_dat))
120 		return PTR_ERR(plat_dat);
121 
122 	plat_dat->init = anarion_gmac_init;
123 	plat_dat->exit = anarion_gmac_exit;
124 	anarion_gmac_init(pdev, gmac);
125 	plat_dat->bsp_priv = gmac;
126 
127 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
128 	if (ret) {
129 		stmmac_remove_config_dt(pdev, plat_dat);
130 		return ret;
131 	}
132 
133 	return 0;
134 }
135 
136 static const struct of_device_id anarion_dwmac_match[] = {
137 	{ .compatible = "adaptrum,anarion-gmac" },
138 	{ }
139 };
140 MODULE_DEVICE_TABLE(of, anarion_dwmac_match);
141 
142 static struct platform_driver anarion_dwmac_driver = {
143 	.probe  = anarion_dwmac_probe,
144 	.remove = stmmac_pltfr_remove,
145 	.driver = {
146 		.name           = "anarion-dwmac",
147 		.pm		= &stmmac_pltfr_pm_ops,
148 		.of_match_table = anarion_dwmac_match,
149 	},
150 };
151 module_platform_driver(anarion_dwmac_driver);
152 
153 MODULE_DESCRIPTION("Adaptrum Anarion DWMAC specific glue layer");
154 MODULE_AUTHOR("Alexandru Gagniuc <mr.nuke.me@gmail.com>");
155 MODULE_LICENSE("GPL v2");
156