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 	struct reset_control *stmmac_rst;
53 	void __iomem *splitter_base;
54 	bool f2h_ptp_ref_clk;
55 };
56 
57 static void socfpga_dwmac_fix_mac_speed(void *priv, unsigned int speed)
58 {
59 	struct socfpga_dwmac *dwmac = (struct socfpga_dwmac *)priv;
60 	void __iomem *splitter_base = dwmac->splitter_base;
61 	u32 val;
62 
63 	if (!splitter_base)
64 		return;
65 
66 	val = readl(splitter_base + EMAC_SPLITTER_CTRL_REG);
67 	val &= ~EMAC_SPLITTER_CTRL_SPEED_MASK;
68 
69 	switch (speed) {
70 	case 1000:
71 		val |= EMAC_SPLITTER_CTRL_SPEED_1000;
72 		break;
73 	case 100:
74 		val |= EMAC_SPLITTER_CTRL_SPEED_100;
75 		break;
76 	case 10:
77 		val |= EMAC_SPLITTER_CTRL_SPEED_10;
78 		break;
79 	default:
80 		return;
81 	}
82 
83 	writel(val, splitter_base + EMAC_SPLITTER_CTRL_REG);
84 }
85 
86 static int socfpga_dwmac_parse_data(struct socfpga_dwmac *dwmac, struct device *dev)
87 {
88 	struct device_node *np = dev->of_node;
89 	struct regmap *sys_mgr_base_addr;
90 	u32 reg_offset, reg_shift;
91 	int ret;
92 	struct device_node *np_splitter;
93 	struct resource res_splitter;
94 
95 	dwmac->stmmac_rst = devm_reset_control_get(dev,
96 						  STMMAC_RESOURCE_NAME);
97 	if (IS_ERR(dwmac->stmmac_rst)) {
98 		dev_info(dev, "Could not get reset control!\n");
99 		if (PTR_ERR(dwmac->stmmac_rst) == -EPROBE_DEFER)
100 			return -EPROBE_DEFER;
101 		dwmac->stmmac_rst = NULL;
102 	}
103 
104 	dwmac->interface = of_get_phy_mode(np);
105 
106 	sys_mgr_base_addr = syscon_regmap_lookup_by_phandle(np, "altr,sysmgr-syscon");
107 	if (IS_ERR(sys_mgr_base_addr)) {
108 		dev_info(dev, "No sysmgr-syscon node found\n");
109 		return PTR_ERR(sys_mgr_base_addr);
110 	}
111 
112 	ret = of_property_read_u32_index(np, "altr,sysmgr-syscon", 1, &reg_offset);
113 	if (ret) {
114 		dev_info(dev, "Could not read reg_offset from sysmgr-syscon!\n");
115 		return -EINVAL;
116 	}
117 
118 	ret = of_property_read_u32_index(np, "altr,sysmgr-syscon", 2, &reg_shift);
119 	if (ret) {
120 		dev_info(dev, "Could not read reg_shift from sysmgr-syscon!\n");
121 		return -EINVAL;
122 	}
123 
124 	dwmac->f2h_ptp_ref_clk = of_property_read_bool(np, "altr,f2h_ptp_ref_clk");
125 
126 	np_splitter = of_parse_phandle(np, "altr,emac-splitter", 0);
127 	if (np_splitter) {
128 		if (of_address_to_resource(np_splitter, 0, &res_splitter)) {
129 			dev_info(dev, "Missing emac splitter address\n");
130 			return -EINVAL;
131 		}
132 
133 		dwmac->splitter_base = devm_ioremap_resource(dev, &res_splitter);
134 		if (IS_ERR(dwmac->splitter_base)) {
135 			dev_info(dev, "Failed to mapping emac splitter\n");
136 			return PTR_ERR(dwmac->splitter_base);
137 		}
138 	}
139 
140 	dwmac->reg_offset = reg_offset;
141 	dwmac->reg_shift = reg_shift;
142 	dwmac->sys_mgr_base_addr = sys_mgr_base_addr;
143 	dwmac->dev = dev;
144 
145 	return 0;
146 }
147 
148 static int socfpga_dwmac_setup(struct socfpga_dwmac *dwmac)
149 {
150 	struct regmap *sys_mgr_base_addr = dwmac->sys_mgr_base_addr;
151 	int phymode = dwmac->interface;
152 	u32 reg_offset = dwmac->reg_offset;
153 	u32 reg_shift = dwmac->reg_shift;
154 	u32 ctrl, val, module;
155 
156 	switch (phymode) {
157 	case PHY_INTERFACE_MODE_RGMII:
158 	case PHY_INTERFACE_MODE_RGMII_ID:
159 		val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_RGMII;
160 		break;
161 	case PHY_INTERFACE_MODE_MII:
162 	case PHY_INTERFACE_MODE_GMII:
163 		val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_GMII_MII;
164 		break;
165 	default:
166 		dev_err(dwmac->dev, "bad phy mode %d\n", phymode);
167 		return -EINVAL;
168 	}
169 
170 	/* Overwrite val to GMII if splitter core is enabled. The phymode here
171 	 * is the actual phy mode on phy hardware, but phy interface from
172 	 * EMAC core is GMII.
173 	 */
174 	if (dwmac->splitter_base)
175 		val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_GMII_MII;
176 
177 	regmap_read(sys_mgr_base_addr, reg_offset, &ctrl);
178 	ctrl &= ~(SYSMGR_EMACGRP_CTRL_PHYSEL_MASK << reg_shift);
179 	ctrl |= val << reg_shift;
180 
181 	if (dwmac->f2h_ptp_ref_clk) {
182 		ctrl |= SYSMGR_EMACGRP_CTRL_PTP_REF_CLK_MASK << (reg_shift / 2);
183 		regmap_read(sys_mgr_base_addr, SYSMGR_FPGAGRP_MODULE_REG,
184 			    &module);
185 		module |= (SYSMGR_FPGAGRP_MODULE_EMAC << (reg_shift / 2));
186 		regmap_write(sys_mgr_base_addr, SYSMGR_FPGAGRP_MODULE_REG,
187 			     module);
188 	} else {
189 		ctrl &= ~(SYSMGR_EMACGRP_CTRL_PTP_REF_CLK_MASK << (reg_shift / 2));
190 	}
191 
192 	regmap_write(sys_mgr_base_addr, reg_offset, ctrl);
193 
194 	return 0;
195 }
196 
197 static void socfpga_dwmac_exit(struct platform_device *pdev, void *priv)
198 {
199 	struct socfpga_dwmac	*dwmac = priv;
200 
201 	/* On socfpga platform exit, assert and hold reset to the
202 	 * enet controller - the default state after a hard reset.
203 	 */
204 	if (dwmac->stmmac_rst)
205 		reset_control_assert(dwmac->stmmac_rst);
206 }
207 
208 static int socfpga_dwmac_init(struct platform_device *pdev, void *priv)
209 {
210 	struct socfpga_dwmac	*dwmac = priv;
211 	struct net_device *ndev = platform_get_drvdata(pdev);
212 	struct stmmac_priv *stpriv = NULL;
213 	int ret = 0;
214 
215 	if (ndev)
216 		stpriv = netdev_priv(ndev);
217 
218 	/* Assert reset to the enet controller before changing the phy mode */
219 	if (dwmac->stmmac_rst)
220 		reset_control_assert(dwmac->stmmac_rst);
221 
222 	/* Setup the phy mode in the system manager registers according to
223 	 * devicetree configuration
224 	 */
225 	ret = socfpga_dwmac_setup(dwmac);
226 
227 	/* Deassert reset for the phy configuration to be sampled by
228 	 * the enet controller, and operation to start in requested mode
229 	 */
230 	if (dwmac->stmmac_rst)
231 		reset_control_deassert(dwmac->stmmac_rst);
232 
233 	/* Before the enet controller is suspended, the phy is suspended.
234 	 * This causes the phy clock to be gated. The enet controller is
235 	 * resumed before the phy, so the clock is still gated "off" when
236 	 * the enet controller is resumed. This code makes sure the phy
237 	 * is "resumed" before reinitializing the enet controller since
238 	 * the enet controller depends on an active phy clock to complete
239 	 * a DMA reset. A DMA reset will "time out" if executed
240 	 * with no phy clock input on the Synopsys enet controller.
241 	 * Verified through Synopsys Case #8000711656.
242 	 *
243 	 * Note that the phy clock is also gated when the phy is isolated.
244 	 * Phy "suspend" and "isolate" controls are located in phy basic
245 	 * control register 0, and can be modified by the phy driver
246 	 * framework.
247 	 */
248 	if (stpriv && stpriv->phydev)
249 		phy_resume(stpriv->phydev);
250 
251 	return ret;
252 }
253 
254 static int socfpga_dwmac_probe(struct platform_device *pdev)
255 {
256 	struct plat_stmmacenet_data *plat_dat;
257 	struct stmmac_resources stmmac_res;
258 	struct device		*dev = &pdev->dev;
259 	int			ret;
260 	struct socfpga_dwmac	*dwmac;
261 
262 	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
263 	if (ret)
264 		return ret;
265 
266 	plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
267 	if (IS_ERR(plat_dat))
268 		return PTR_ERR(plat_dat);
269 
270 	dwmac = devm_kzalloc(dev, sizeof(*dwmac), GFP_KERNEL);
271 	if (!dwmac)
272 		return -ENOMEM;
273 
274 	ret = socfpga_dwmac_parse_data(dwmac, dev);
275 	if (ret) {
276 		dev_err(dev, "Unable to parse OF data\n");
277 		return ret;
278 	}
279 
280 	ret = socfpga_dwmac_setup(dwmac);
281 	if (ret) {
282 		dev_err(dev, "couldn't setup SoC glue (%d)\n", ret);
283 		return ret;
284 	}
285 
286 	plat_dat->bsp_priv = dwmac;
287 	plat_dat->init = socfpga_dwmac_init;
288 	plat_dat->exit = socfpga_dwmac_exit;
289 	plat_dat->fix_mac_speed = socfpga_dwmac_fix_mac_speed;
290 
291 	ret = socfpga_dwmac_init(pdev, plat_dat->bsp_priv);
292 	if (ret)
293 		return ret;
294 
295 	return stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
296 }
297 
298 static const struct of_device_id socfpga_dwmac_match[] = {
299 	{ .compatible = "altr,socfpga-stmmac" },
300 	{ }
301 };
302 MODULE_DEVICE_TABLE(of, socfpga_dwmac_match);
303 
304 static struct platform_driver socfpga_dwmac_driver = {
305 	.probe  = socfpga_dwmac_probe,
306 	.remove = stmmac_pltfr_remove,
307 	.driver = {
308 		.name           = "socfpga-dwmac",
309 		.pm		= &stmmac_pltfr_pm_ops,
310 		.of_match_table = socfpga_dwmac_match,
311 	},
312 };
313 module_platform_driver(socfpga_dwmac_driver);
314 
315 MODULE_LICENSE("GPL v2");
316