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
36 #define EMAC_SPLITTER_CTRL_REG 0x0
37 #define EMAC_SPLITTER_CTRL_SPEED_MASK 0x3
38 #define EMAC_SPLITTER_CTRL_SPEED_10 0x2
39 #define EMAC_SPLITTER_CTRL_SPEED_100 0x3
40 #define EMAC_SPLITTER_CTRL_SPEED_1000 0x0
41
42 struct socfpga_dwmac {
43 int interface;
44 u32 reg_offset;
45 u32 reg_shift;
46 struct device *dev;
47 struct regmap *sys_mgr_base_addr;
48 struct reset_control *stmmac_rst;
49 void __iomem *splitter_base;
50 };
51
socfpga_dwmac_fix_mac_speed(void * priv,unsigned int speed)52 static void socfpga_dwmac_fix_mac_speed(void *priv, unsigned int speed)
53 {
54 struct socfpga_dwmac *dwmac = (struct socfpga_dwmac *)priv;
55 void __iomem *splitter_base = dwmac->splitter_base;
56 u32 val;
57
58 if (!splitter_base)
59 return;
60
61 val = readl(splitter_base + EMAC_SPLITTER_CTRL_REG);
62 val &= ~EMAC_SPLITTER_CTRL_SPEED_MASK;
63
64 switch (speed) {
65 case 1000:
66 val |= EMAC_SPLITTER_CTRL_SPEED_1000;
67 break;
68 case 100:
69 val |= EMAC_SPLITTER_CTRL_SPEED_100;
70 break;
71 case 10:
72 val |= EMAC_SPLITTER_CTRL_SPEED_10;
73 break;
74 default:
75 return;
76 }
77
78 writel(val, splitter_base + EMAC_SPLITTER_CTRL_REG);
79 }
80
socfpga_dwmac_parse_data(struct socfpga_dwmac * dwmac,struct device * dev)81 static int socfpga_dwmac_parse_data(struct socfpga_dwmac *dwmac, struct device *dev)
82 {
83 struct device_node *np = dev->of_node;
84 struct regmap *sys_mgr_base_addr;
85 u32 reg_offset, reg_shift;
86 int ret;
87 struct device_node *np_splitter;
88 struct resource res_splitter;
89
90 dwmac->stmmac_rst = devm_reset_control_get(dev,
91 STMMAC_RESOURCE_NAME);
92 if (IS_ERR(dwmac->stmmac_rst)) {
93 dev_info(dev, "Could not get reset control!\n");
94 if (PTR_ERR(dwmac->stmmac_rst) == -EPROBE_DEFER)
95 return -EPROBE_DEFER;
96 dwmac->stmmac_rst = NULL;
97 }
98
99 dwmac->interface = of_get_phy_mode(np);
100
101 sys_mgr_base_addr = syscon_regmap_lookup_by_phandle(np, "altr,sysmgr-syscon");
102 if (IS_ERR(sys_mgr_base_addr)) {
103 dev_info(dev, "No sysmgr-syscon node found\n");
104 return PTR_ERR(sys_mgr_base_addr);
105 }
106
107 ret = of_property_read_u32_index(np, "altr,sysmgr-syscon", 1, ®_offset);
108 if (ret) {
109 dev_info(dev, "Could not read reg_offset from sysmgr-syscon!\n");
110 return -EINVAL;
111 }
112
113 ret = of_property_read_u32_index(np, "altr,sysmgr-syscon", 2, ®_shift);
114 if (ret) {
115 dev_info(dev, "Could not read reg_shift from sysmgr-syscon!\n");
116 return -EINVAL;
117 }
118
119 np_splitter = of_parse_phandle(np, "altr,emac-splitter", 0);
120 if (np_splitter) {
121 if (of_address_to_resource(np_splitter, 0, &res_splitter)) {
122 dev_info(dev, "Missing emac splitter address\n");
123 return -EINVAL;
124 }
125
126 dwmac->splitter_base = devm_ioremap_resource(dev, &res_splitter);
127 if (IS_ERR(dwmac->splitter_base)) {
128 dev_info(dev, "Failed to mapping emac splitter\n");
129 return PTR_ERR(dwmac->splitter_base);
130 }
131 }
132
133 dwmac->reg_offset = reg_offset;
134 dwmac->reg_shift = reg_shift;
135 dwmac->sys_mgr_base_addr = sys_mgr_base_addr;
136 dwmac->dev = dev;
137
138 return 0;
139 }
140
socfpga_dwmac_setup(struct socfpga_dwmac * dwmac)141 static int socfpga_dwmac_setup(struct socfpga_dwmac *dwmac)
142 {
143 struct regmap *sys_mgr_base_addr = dwmac->sys_mgr_base_addr;
144 int phymode = dwmac->interface;
145 u32 reg_offset = dwmac->reg_offset;
146 u32 reg_shift = dwmac->reg_shift;
147 u32 ctrl, val;
148
149 switch (phymode) {
150 case PHY_INTERFACE_MODE_RGMII:
151 case PHY_INTERFACE_MODE_RGMII_ID:
152 val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_RGMII;
153 break;
154 case PHY_INTERFACE_MODE_MII:
155 case PHY_INTERFACE_MODE_GMII:
156 val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_GMII_MII;
157 break;
158 default:
159 dev_err(dwmac->dev, "bad phy mode %d\n", phymode);
160 return -EINVAL;
161 }
162
163 /* Overwrite val to GMII if splitter core is enabled. The phymode here
164 * is the actual phy mode on phy hardware, but phy interface from
165 * EMAC core is GMII.
166 */
167 if (dwmac->splitter_base)
168 val = SYSMGR_EMACGRP_CTRL_PHYSEL_ENUM_GMII_MII;
169
170 regmap_read(sys_mgr_base_addr, reg_offset, &ctrl);
171 ctrl &= ~(SYSMGR_EMACGRP_CTRL_PHYSEL_MASK << reg_shift);
172 ctrl |= val << reg_shift;
173
174 regmap_write(sys_mgr_base_addr, reg_offset, ctrl);
175 return 0;
176 }
177
socfpga_dwmac_probe(struct platform_device * pdev)178 static void *socfpga_dwmac_probe(struct platform_device *pdev)
179 {
180 struct device *dev = &pdev->dev;
181 int ret;
182 struct socfpga_dwmac *dwmac;
183
184 dwmac = devm_kzalloc(dev, sizeof(*dwmac), GFP_KERNEL);
185 if (!dwmac)
186 return ERR_PTR(-ENOMEM);
187
188 ret = socfpga_dwmac_parse_data(dwmac, dev);
189 if (ret) {
190 dev_err(dev, "Unable to parse OF data\n");
191 return ERR_PTR(ret);
192 }
193
194 ret = socfpga_dwmac_setup(dwmac);
195 if (ret) {
196 dev_err(dev, "couldn't setup SoC glue (%d)\n", ret);
197 return ERR_PTR(ret);
198 }
199
200 return dwmac;
201 }
202
socfpga_dwmac_exit(struct platform_device * pdev,void * priv)203 static void socfpga_dwmac_exit(struct platform_device *pdev, void *priv)
204 {
205 struct socfpga_dwmac *dwmac = priv;
206
207 /* On socfpga platform exit, assert and hold reset to the
208 * enet controller - the default state after a hard reset.
209 */
210 if (dwmac->stmmac_rst)
211 reset_control_assert(dwmac->stmmac_rst);
212 }
213
socfpga_dwmac_init(struct platform_device * pdev,void * priv)214 static int socfpga_dwmac_init(struct platform_device *pdev, void *priv)
215 {
216 struct socfpga_dwmac *dwmac = priv;
217 struct net_device *ndev = platform_get_drvdata(pdev);
218 struct stmmac_priv *stpriv = NULL;
219 int ret = 0;
220
221 if (ndev)
222 stpriv = netdev_priv(ndev);
223
224 /* Assert reset to the enet controller before changing the phy mode */
225 if (dwmac->stmmac_rst)
226 reset_control_assert(dwmac->stmmac_rst);
227
228 /* Setup the phy mode in the system manager registers according to
229 * devicetree configuration
230 */
231 ret = socfpga_dwmac_setup(dwmac);
232
233 /* Deassert reset for the phy configuration to be sampled by
234 * the enet controller, and operation to start in requested mode
235 */
236 if (dwmac->stmmac_rst)
237 reset_control_deassert(dwmac->stmmac_rst);
238
239 /* Before the enet controller is suspended, the phy is suspended.
240 * This causes the phy clock to be gated. The enet controller is
241 * resumed before the phy, so the clock is still gated "off" when
242 * the enet controller is resumed. This code makes sure the phy
243 * is "resumed" before reinitializing the enet controller since
244 * the enet controller depends on an active phy clock to complete
245 * a DMA reset. A DMA reset will "time out" if executed
246 * with no phy clock input on the Synopsys enet controller.
247 * Verified through Synopsys Case #8000711656.
248 *
249 * Note that the phy clock is also gated when the phy is isolated.
250 * Phy "suspend" and "isolate" controls are located in phy basic
251 * control register 0, and can be modified by the phy driver
252 * framework.
253 */
254 if (stpriv && stpriv->phydev)
255 phy_resume(stpriv->phydev);
256
257 return ret;
258 }
259
260 const struct stmmac_of_data socfpga_gmac_data = {
261 .setup = socfpga_dwmac_probe,
262 .init = socfpga_dwmac_init,
263 .exit = socfpga_dwmac_exit,
264 .fix_mac_speed = socfpga_dwmac_fix_mac_speed,
265 };
266