1 /*
2  * Adaptrum Anarion DWMAC glue layer
3  *
4  * Copyright (C) 2017, Adaptrum, Inc.
5  * (Written by Alexandru Gagniuc <alex.g at adaptrum.com> for Adaptrum, Inc.)
6  * Licensed under the GPLv2 or (at your option) any later version.
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 	int phy_mode;
65 	struct resource *res;
66 	void __iomem *ctl_block;
67 	struct anarion_gmac *gmac;
68 
69 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
70 	ctl_block = devm_ioremap_resource(&pdev->dev, res);
71 	if (IS_ERR(ctl_block)) {
72 		dev_err(&pdev->dev, "Cannot get reset region (%ld)!\n",
73 			PTR_ERR(ctl_block));
74 		return ctl_block;
75 	}
76 
77 	gmac = devm_kzalloc(&pdev->dev, sizeof(*gmac), GFP_KERNEL);
78 	if (!gmac)
79 		return ERR_PTR(-ENOMEM);
80 
81 	gmac->ctl_block = (uintptr_t)ctl_block;
82 
83 	phy_mode = of_get_phy_mode(pdev->dev.of_node);
84 	switch (phy_mode) {
85 	case PHY_INTERFACE_MODE_RGMII:		/* Fall through */
86 	case PHY_INTERFACE_MODE_RGMII_ID	/* Fall through */:
87 	case PHY_INTERFACE_MODE_RGMII_RXID:	/* Fall through */
88 	case PHY_INTERFACE_MODE_RGMII_TXID:
89 		gmac->phy_intf_sel = GMAC_CONFIG_INTF_RGMII;
90 		break;
91 	default:
92 		dev_err(&pdev->dev, "Unsupported phy-mode (%d)\n",
93 			phy_mode);
94 		return ERR_PTR(-ENOTSUPP);
95 	}
96 
97 	return gmac;
98 }
99 
100 static int anarion_dwmac_probe(struct platform_device *pdev)
101 {
102 	int ret;
103 	struct anarion_gmac *gmac;
104 	struct plat_stmmacenet_data *plat_dat;
105 	struct stmmac_resources stmmac_res;
106 
107 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
108 	if (ret)
109 		return ret;
110 
111 	gmac = anarion_config_dt(pdev);
112 	if (IS_ERR(gmac))
113 		return PTR_ERR(gmac);
114 
115 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
116 	if (IS_ERR(plat_dat))
117 		return PTR_ERR(plat_dat);
118 
119 	plat_dat->init = anarion_gmac_init;
120 	plat_dat->exit = anarion_gmac_exit;
121 	anarion_gmac_init(pdev, gmac);
122 	plat_dat->bsp_priv = gmac;
123 
124 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
125 	if (ret) {
126 		stmmac_remove_config_dt(pdev, plat_dat);
127 		return ret;
128 	}
129 
130 	return 0;
131 }
132 
133 static const struct of_device_id anarion_dwmac_match[] = {
134 	{ .compatible = "adaptrum,anarion-gmac" },
135 	{ }
136 };
137 MODULE_DEVICE_TABLE(of, anarion_dwmac_match);
138 
139 static struct platform_driver anarion_dwmac_driver = {
140 	.probe  = anarion_dwmac_probe,
141 	.remove = stmmac_pltfr_remove,
142 	.driver = {
143 		.name           = "anarion-dwmac",
144 		.pm		= &stmmac_pltfr_pm_ops,
145 		.of_match_table = anarion_dwmac_match,
146 	},
147 };
148 module_platform_driver(anarion_dwmac_driver);
149 
150 MODULE_DESCRIPTION("Adaptrum Anarion DWMAC specific glue layer");
151 MODULE_AUTHOR("Alexandru Gagniuc <mr.nuke.me@gmail.com>");
152 MODULE_LICENSE("GPL v2");
153