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:		/* Fall through */
88 	case PHY_INTERFACE_MODE_RGMII_ID	/* Fall through */:
89 	case PHY_INTERFACE_MODE_RGMII_RXID:	/* Fall through */
90 	case PHY_INTERFACE_MODE_RGMII_TXID:
91 		gmac->phy_intf_sel = GMAC_CONFIG_INTF_RGMII;
92 		break;
93 	default:
94 		dev_err(&pdev->dev, "Unsupported phy-mode (%d)\n",
95 			phy_mode);
96 		return ERR_PTR(-ENOTSUPP);
97 	}
98 
99 	return gmac;
100 }
101 
102 static int anarion_dwmac_probe(struct platform_device *pdev)
103 {
104 	int ret;
105 	struct anarion_gmac *gmac;
106 	struct plat_stmmacenet_data *plat_dat;
107 	struct stmmac_resources stmmac_res;
108 
109 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
110 	if (ret)
111 		return ret;
112 
113 	gmac = anarion_config_dt(pdev);
114 	if (IS_ERR(gmac))
115 		return PTR_ERR(gmac);
116 
117 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
118 	if (IS_ERR(plat_dat))
119 		return PTR_ERR(plat_dat);
120 
121 	plat_dat->init = anarion_gmac_init;
122 	plat_dat->exit = anarion_gmac_exit;
123 	anarion_gmac_init(pdev, gmac);
124 	plat_dat->bsp_priv = gmac;
125 
126 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
127 	if (ret) {
128 		stmmac_remove_config_dt(pdev, plat_dat);
129 		return ret;
130 	}
131 
132 	return 0;
133 }
134 
135 static const struct of_device_id anarion_dwmac_match[] = {
136 	{ .compatible = "adaptrum,anarion-gmac" },
137 	{ }
138 };
139 MODULE_DEVICE_TABLE(of, anarion_dwmac_match);
140 
141 static struct platform_driver anarion_dwmac_driver = {
142 	.probe  = anarion_dwmac_probe,
143 	.remove = stmmac_pltfr_remove,
144 	.driver = {
145 		.name           = "anarion-dwmac",
146 		.pm		= &stmmac_pltfr_pm_ops,
147 		.of_match_table = anarion_dwmac_match,
148 	},
149 };
150 module_platform_driver(anarion_dwmac_driver);
151 
152 MODULE_DESCRIPTION("Adaptrum Anarion DWMAC specific glue layer");
153 MODULE_AUTHOR("Alexandru Gagniuc <mr.nuke.me@gmail.com>");
154 MODULE_LICENSE("GPL v2");
155