1 /* Copyright Altera Corporation (C) 2014. All rights reserved.
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License, version 2,
5  * as published by the Free Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  *
12  * You should have received a copy of the GNU General Public License
13  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
14  *
15  * Adopted from dwmac-sti.c
16  */
17 
18 #include <linux/mfd/syscon.h>
19 #include <linux/of.h>
20 #include <linux/of_address.h>
21 #include <linux/of_net.h>
22 #include <linux/phy.h>
23 #include <linux/regmap.h>
24 #include <linux/reset.h>
25 #include <linux/stmmac.h>
26 
27 #include "stmmac.h"
28 #include "stmmac_platform.h"
29 
30 #define SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_GMII_MII 0x0
31 #define SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_RGMII 0x1
32 #define SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_RMII 0x2
33 #define SYSMGR_EMACGRP_CTRL_PHYSEL_WIDTH 2
34 #define SYSMGR_EMACGRP_CTRL_PHYSEL_MASK 0x00000003
35 #define SYSMGR_EMACGRP_CTRL_PTP_REF_CLK_MASK 0x00000010
36 
37 #define SYSMGR_FPGAGRP_MODULE_REG  0x00000028
38 #define SYSMGR_FPGAGRP_MODULE_EMAC 0x00000004
39 
40 #define EMAC_SPLITTER_CTRL_REG			0x0
41 #define EMAC_SPLITTER_CTRL_SPEED_MASK		0x3
42 #define EMAC_SPLITTER_CTRL_SPEED_10		0x2
43 #define EMAC_SPLITTER_CTRL_SPEED_100		0x3
44 #define EMAC_SPLITTER_CTRL_SPEED_1000		0x0
45 
46 struct socfpga_dwmac {
47 	int	interface;
48 	u32	reg_offset;
49 	u32	reg_shift;
50 	struct	device *dev;
51 	struct regmap *sys_mgr_base_addr;
52 	void __iomem *splitter_base;
53 	bool f2h_ptp_ref_clk;
54 };
55 
56 static void socfpga_dwmac_fix_mac_speed(void *priv, unsigned int speed)
57 {
58 	struct socfpga_dwmac *dwmac = (struct socfpga_dwmac *)priv;
59 	void __iomem *splitter_base = dwmac->splitter_base;
60 	u32 val;
61 
62 	if (!splitter_base)
63 		return;
64 
65 	val = readl(splitter_base + EMAC_SPLITTER_CTRL_REG);
66 	val &= ~EMAC_SPLITTER_CTRL_SPEED_MASK;
67 
68 	switch (speed) {
69 	case 1000:
70 		val |= EMAC_SPLITTER_CTRL_SPEED_1000;
71 		break;
72 	case 100:
73 		val |= EMAC_SPLITTER_CTRL_SPEED_100;
74 		break;
75 	case 10:
76 		val |= EMAC_SPLITTER_CTRL_SPEED_10;
77 		break;
78 	default:
79 		return;
80 	}
81 
82 	writel(val, splitter_base + EMAC_SPLITTER_CTRL_REG);
83 }
84 
85 static int socfpga_dwmac_parse_data(struct socfpga_dwmac *dwmac, struct device *dev)
86 {
87 	struct device_node *np = dev->of_node;
88 	struct regmap *sys_mgr_base_addr;
89 	u32 reg_offset, reg_shift;
90 	int ret;
91 	struct device_node *np_splitter;
92 	struct resource res_splitter;
93 
94 	dwmac->interface = of_get_phy_mode(np);
95 
96 	sys_mgr_base_addr = syscon_regmap_lookup_by_phandle(np, "altr,sysmgr-syscon");
97 	if (IS_ERR(sys_mgr_base_addr)) {
98 		dev_info(dev, "No sysmgr-syscon node found\n");
99 		return PTR_ERR(sys_mgr_base_addr);
100 	}
101 
102 	ret = of_property_read_u32_index(np, "altr,sysmgr-syscon", 1, &reg_offset);
103 	if (ret) {
104 		dev_info(dev, "Could not read reg_offset from sysmgr-syscon!\n");
105 		return -EINVAL;
106 	}
107 
108 	ret = of_property_read_u32_index(np, "altr,sysmgr-syscon", 2, &reg_shift);
109 	if (ret) {
110 		dev_info(dev, "Could not read reg_shift from sysmgr-syscon!\n");
111 		return -EINVAL;
112 	}
113 
114 	dwmac->f2h_ptp_ref_clk = of_property_read_bool(np, "altr,f2h_ptp_ref_clk");
115 
116 	np_splitter = of_parse_phandle(np, "altr,emac-splitter", 0);
117 	if (np_splitter) {
118 		if (of_address_to_resource(np_splitter, 0, &res_splitter)) {
119 			dev_info(dev, "Missing emac splitter address\n");
120 			return -EINVAL;
121 		}
122 
123 		dwmac->splitter_base = devm_ioremap_resource(dev, &res_splitter);
124 		if (IS_ERR(dwmac->splitter_base)) {
125 			dev_info(dev, "Failed to mapping emac splitter\n");
126 			return PTR_ERR(dwmac->splitter_base);
127 		}
128 	}
129 
130 	dwmac->reg_offset = reg_offset;
131 	dwmac->reg_shift = reg_shift;
132 	dwmac->sys_mgr_base_addr = sys_mgr_base_addr;
133 	dwmac->dev = dev;
134 
135 	return 0;
136 }
137 
138 static int socfpga_dwmac_setup(struct socfpga_dwmac *dwmac)
139 {
140 	struct regmap *sys_mgr_base_addr = dwmac->sys_mgr_base_addr;
141 	int phymode = dwmac->interface;
142 	u32 reg_offset = dwmac->reg_offset;
143 	u32 reg_shift = dwmac->reg_shift;
144 	u32 ctrl, val, module;
145 
146 	switch (phymode) {
147 	case PHY_INTERFACE_MODE_RGMII:
148 	case PHY_INTERFACE_MODE_RGMII_ID:
149 		val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_RGMII;
150 		break;
151 	case PHY_INTERFACE_MODE_MII:
152 	case PHY_INTERFACE_MODE_GMII:
153 		val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_GMII_MII;
154 		break;
155 	default:
156 		dev_err(dwmac->dev, "bad phy mode %d\n", phymode);
157 		return -EINVAL;
158 	}
159 
160 	/* Overwrite val to GMII if splitter core is enabled. The phymode here
161 	 * is the actual phy mode on phy hardware, but phy interface from
162 	 * EMAC core is GMII.
163 	 */
164 	if (dwmac->splitter_base)
165 		val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_GMII_MII;
166 
167 	regmap_read(sys_mgr_base_addr, reg_offset, &ctrl);
168 	ctrl &= ~(SYSMGR_EMACGRP_CTRL_PHYSEL_MASK << reg_shift);
169 	ctrl |= val << reg_shift;
170 
171 	if (dwmac->f2h_ptp_ref_clk) {
172 		ctrl |= SYSMGR_EMACGRP_CTRL_PTP_REF_CLK_MASK << (reg_shift / 2);
173 		regmap_read(sys_mgr_base_addr, SYSMGR_FPGAGRP_MODULE_REG,
174 			    &module);
175 		module |= (SYSMGR_FPGAGRP_MODULE_EMAC << (reg_shift / 2));
176 		regmap_write(sys_mgr_base_addr, SYSMGR_FPGAGRP_MODULE_REG,
177 			     module);
178 	} else {
179 		ctrl &= ~(SYSMGR_EMACGRP_CTRL_PTP_REF_CLK_MASK << (reg_shift / 2));
180 	}
181 
182 	regmap_write(sys_mgr_base_addr, reg_offset, ctrl);
183 
184 	return 0;
185 }
186 
187 static int socfpga_dwmac_init(struct platform_device *pdev, void *priv)
188 {
189 	struct socfpga_dwmac *dwmac = priv;
190 	struct net_device *ndev = platform_get_drvdata(pdev);
191 	struct stmmac_priv *stpriv = NULL;
192 	int ret = 0;
193 
194 	if (!ndev)
195 		return -EINVAL;
196 
197 	stpriv = netdev_priv(ndev);
198 	if (!stpriv)
199 		return -EINVAL;
200 
201 	/* Assert reset to the enet controller before changing the phy mode */
202 	if (stpriv->stmmac_rst)
203 		reset_control_assert(stpriv->stmmac_rst);
204 
205 	/* Setup the phy mode in the system manager registers according to
206 	 * devicetree configuration
207 	 */
208 	ret = socfpga_dwmac_setup(dwmac);
209 
210 	/* Deassert reset for the phy configuration to be sampled by
211 	 * the enet controller, and operation to start in requested mode
212 	 */
213 	if (stpriv->stmmac_rst)
214 		reset_control_deassert(stpriv->stmmac_rst);
215 
216 	/* Before the enet controller is suspended, the phy is suspended.
217 	 * This causes the phy clock to be gated. The enet controller is
218 	 * resumed before the phy, so the clock is still gated "off" when
219 	 * the enet controller is resumed. This code makes sure the phy
220 	 * is "resumed" before reinitializing the enet controller since
221 	 * the enet controller depends on an active phy clock to complete
222 	 * a DMA reset. A DMA reset will "time out" if executed
223 	 * with no phy clock input on the Synopsys enet controller.
224 	 * Verified through Synopsys Case #8000711656.
225 	 *
226 	 * Note that the phy clock is also gated when the phy is isolated.
227 	 * Phy "suspend" and "isolate" controls are located in phy basic
228 	 * control register 0, and can be modified by the phy driver
229 	 * framework.
230 	 */
231 	if (stpriv->phydev)
232 		phy_resume(stpriv->phydev);
233 
234 	return ret;
235 }
236 
237 static int socfpga_dwmac_probe(struct platform_device *pdev)
238 {
239 	struct plat_stmmacenet_data *plat_dat;
240 	struct stmmac_resources stmmac_res;
241 	struct device		*dev = &pdev->dev;
242 	int			ret;
243 	struct socfpga_dwmac	*dwmac;
244 
245 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
246 	if (ret)
247 		return ret;
248 
249 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
250 	if (IS_ERR(plat_dat))
251 		return PTR_ERR(plat_dat);
252 
253 	dwmac = devm_kzalloc(dev, sizeof(*dwmac), GFP_KERNEL);
254 	if (!dwmac)
255 		return -ENOMEM;
256 
257 	ret = socfpga_dwmac_parse_data(dwmac, dev);
258 	if (ret) {
259 		dev_err(dev, "Unable to parse OF data\n");
260 		return ret;
261 	}
262 
263 	plat_dat->bsp_priv = dwmac;
264 	plat_dat->fix_mac_speed = socfpga_dwmac_fix_mac_speed;
265 
266 	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
267 	if (!ret)
268 		ret = socfpga_dwmac_init(pdev, dwmac);
269 
270 	return ret;
271 }
272 
273 #ifdef CONFIG_PM_SLEEP
274 static int socfpga_dwmac_resume(struct device *dev)
275 {
276 	struct platform_device *pdev = to_platform_device(dev);
277 	struct net_device *ndev = dev_get_drvdata(dev);
278 	struct stmmac_priv *priv = netdev_priv(ndev);
279 
280 	socfpga_dwmac_init(pdev, priv->plat->bsp_priv);
281 
282 	return stmmac_resume(dev);
283 }
284 #endif /* CONFIG_PM_SLEEP */
285 
286 SIMPLE_DEV_PM_OPS(socfpga_dwmac_pm_ops, stmmac_suspend, socfpga_dwmac_resume);
287 
288 static const struct of_device_id socfpga_dwmac_match[] = {
289 	{ .compatible = "altr,socfpga-stmmac" },
290 	{ }
291 };
292 MODULE_DEVICE_TABLE(of, socfpga_dwmac_match);
293 
294 static struct platform_driver socfpga_dwmac_driver = {
295 	.probe  = socfpga_dwmac_probe,
296 	.remove = stmmac_pltfr_remove,
297 	.driver = {
298 		.name           = "socfpga-dwmac",
299 		.pm		= &socfpga_dwmac_pm_ops,
300 		.of_match_table = socfpga_dwmac_match,
301 	},
302 };
303 module_platform_driver(socfpga_dwmac_driver);
304 
305 MODULE_LICENSE("GPL v2");
306