1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014-2015, NVIDIA CORPORATION.  All rights reserved.
4  */
5 
6 #define pr_fmt(fmt) "tegra-xusb-padctl: " fmt
7 
8 #include <common.h>
9 #include <errno.h>
10 
11 #include "xusb-padctl-common.h"
12 
13 #include <asm/arch/clock.h>
14 
tegra_xusb_phy_prepare(struct tegra_xusb_phy * phy)15 int tegra_xusb_phy_prepare(struct tegra_xusb_phy *phy)
16 {
17 	if (phy && phy->ops && phy->ops->prepare)
18 		return phy->ops->prepare(phy);
19 
20 	return phy ? -ENOSYS : -EINVAL;
21 }
22 
tegra_xusb_phy_enable(struct tegra_xusb_phy * phy)23 int tegra_xusb_phy_enable(struct tegra_xusb_phy *phy)
24 {
25 	if (phy && phy->ops && phy->ops->enable)
26 		return phy->ops->enable(phy);
27 
28 	return phy ? -ENOSYS : -EINVAL;
29 }
30 
tegra_xusb_phy_disable(struct tegra_xusb_phy * phy)31 int tegra_xusb_phy_disable(struct tegra_xusb_phy *phy)
32 {
33 	if (phy && phy->ops && phy->ops->disable)
34 		return phy->ops->disable(phy);
35 
36 	return phy ? -ENOSYS : -EINVAL;
37 }
38 
tegra_xusb_phy_unprepare(struct tegra_xusb_phy * phy)39 int tegra_xusb_phy_unprepare(struct tegra_xusb_phy *phy)
40 {
41 	if (phy && phy->ops && phy->ops->unprepare)
42 		return phy->ops->unprepare(phy);
43 
44 	return phy ? -ENOSYS : -EINVAL;
45 }
46 
tegra_xusb_phy_get(unsigned int type)47 struct tegra_xusb_phy *tegra_xusb_phy_get(unsigned int type)
48 {
49 	struct tegra_xusb_phy *phy;
50 	int i;
51 
52 	for (i = 0; i < padctl.socdata->num_phys; i++) {
53 		phy = &padctl.socdata->phys[i];
54 		if (phy->type != type)
55 			continue;
56 		return phy;
57 	}
58 
59 	return NULL;
60 }
61 
62 static const struct tegra_xusb_padctl_lane *
tegra_xusb_padctl_find_lane(struct tegra_xusb_padctl * padctl,const char * name)63 tegra_xusb_padctl_find_lane(struct tegra_xusb_padctl *padctl, const char *name)
64 {
65 	unsigned int i;
66 
67 	for (i = 0; i < padctl->socdata->num_lanes; i++)
68 		if (strcmp(name, padctl->socdata->lanes[i].name) == 0)
69 			return &padctl->socdata->lanes[i];
70 
71 	return NULL;
72 }
73 
74 static int
tegra_xusb_padctl_group_parse_dt(struct tegra_xusb_padctl * padctl,struct tegra_xusb_padctl_group * group,ofnode node)75 tegra_xusb_padctl_group_parse_dt(struct tegra_xusb_padctl *padctl,
76 				 struct tegra_xusb_padctl_group *group,
77 				 ofnode node)
78 {
79 	unsigned int i;
80 	int len, ret;
81 
82 	group->name = ofnode_get_name(node);
83 
84 	len = ofnode_read_string_count(node, "nvidia,lanes");
85 	if (len < 0) {
86 		pr_err("failed to parse \"nvidia,lanes\" property");
87 		return -EINVAL;
88 	}
89 
90 	group->num_pins = len;
91 
92 	for (i = 0; i < group->num_pins; i++) {
93 		ret = ofnode_read_string_index(node, "nvidia,lanes", i,
94 					       &group->pins[i]);
95 		if (ret) {
96 			pr_err("failed to read string from \"nvidia,lanes\" property");
97 			return -EINVAL;
98 		}
99 	}
100 
101 	group->num_pins = len;
102 
103 	ret = ofnode_read_string_index(node, "nvidia,function", 0,
104 				       &group->func);
105 	if (ret) {
106 		pr_err("failed to parse \"nvidia,func\" property");
107 		return -EINVAL;
108 	}
109 
110 	group->iddq = ofnode_read_u32_default(node, "nvidia,iddq", -1);
111 
112 	return 0;
113 }
114 
tegra_xusb_padctl_find_function(struct tegra_xusb_padctl * padctl,const char * name)115 static int tegra_xusb_padctl_find_function(struct tegra_xusb_padctl *padctl,
116 					   const char *name)
117 {
118 	unsigned int i;
119 
120 	for (i = 0; i < padctl->socdata->num_functions; i++)
121 		if (strcmp(name, padctl->socdata->functions[i]) == 0)
122 			return i;
123 
124 	return -ENOENT;
125 }
126 
127 static int
tegra_xusb_padctl_lane_find_function(struct tegra_xusb_padctl * padctl,const struct tegra_xusb_padctl_lane * lane,const char * name)128 tegra_xusb_padctl_lane_find_function(struct tegra_xusb_padctl *padctl,
129 				     const struct tegra_xusb_padctl_lane *lane,
130 				     const char *name)
131 {
132 	unsigned int i;
133 	int func;
134 
135 	func = tegra_xusb_padctl_find_function(padctl, name);
136 	if (func < 0)
137 		return func;
138 
139 	for (i = 0; i < lane->num_funcs; i++)
140 		if (lane->funcs[i] == func)
141 			return i;
142 
143 	return -ENOENT;
144 }
145 
146 static int
tegra_xusb_padctl_group_apply(struct tegra_xusb_padctl * padctl,const struct tegra_xusb_padctl_group * group)147 tegra_xusb_padctl_group_apply(struct tegra_xusb_padctl *padctl,
148 			      const struct tegra_xusb_padctl_group *group)
149 {
150 	unsigned int i;
151 
152 	for (i = 0; i < group->num_pins; i++) {
153 		const struct tegra_xusb_padctl_lane *lane;
154 		unsigned int func;
155 		u32 value;
156 
157 		lane = tegra_xusb_padctl_find_lane(padctl, group->pins[i]);
158 		if (!lane) {
159 			pr_err("no lane for pin %s", group->pins[i]);
160 			continue;
161 		}
162 
163 		func = tegra_xusb_padctl_lane_find_function(padctl, lane,
164 							    group->func);
165 		if (func < 0) {
166 			pr_err("function %s invalid for lane %s: %d",
167 			      group->func, lane->name, func);
168 			continue;
169 		}
170 
171 		value = padctl_readl(padctl, lane->offset);
172 
173 		/* set pin function */
174 		value &= ~(lane->mask << lane->shift);
175 		value |= func << lane->shift;
176 
177 		/*
178 		 * Set IDDQ if supported on the lane and specified in the
179 		 * configuration.
180 		 */
181 		if (lane->iddq > 0 && group->iddq >= 0) {
182 			if (group->iddq != 0)
183 				value &= ~(1 << lane->iddq);
184 			else
185 				value |= 1 << lane->iddq;
186 		}
187 
188 		padctl_writel(padctl, value, lane->offset);
189 	}
190 
191 	return 0;
192 }
193 
194 static int
tegra_xusb_padctl_config_apply(struct tegra_xusb_padctl * padctl,struct tegra_xusb_padctl_config * config)195 tegra_xusb_padctl_config_apply(struct tegra_xusb_padctl *padctl,
196 			       struct tegra_xusb_padctl_config *config)
197 {
198 	unsigned int i;
199 
200 	for (i = 0; i < config->num_groups; i++) {
201 		const struct tegra_xusb_padctl_group *group;
202 		int err;
203 
204 		group = &config->groups[i];
205 
206 		err = tegra_xusb_padctl_group_apply(padctl, group);
207 		if (err < 0) {
208 			pr_err("failed to apply group %s: %d",
209 			      group->name, err);
210 			continue;
211 		}
212 	}
213 
214 	return 0;
215 }
216 
217 static int
tegra_xusb_padctl_config_parse_dt(struct tegra_xusb_padctl * padctl,struct tegra_xusb_padctl_config * config,ofnode node)218 tegra_xusb_padctl_config_parse_dt(struct tegra_xusb_padctl *padctl,
219 				  struct tegra_xusb_padctl_config *config,
220 				  ofnode node)
221 {
222 	ofnode subnode;
223 
224 	config->name = ofnode_get_name(node);
225 
226 	ofnode_for_each_subnode(subnode, node) {
227 		struct tegra_xusb_padctl_group *group;
228 		int err;
229 
230 		group = &config->groups[config->num_groups];
231 
232 		err = tegra_xusb_padctl_group_parse_dt(padctl, group, subnode);
233 		if (err < 0) {
234 			pr_err("failed to parse group %s", group->name);
235 			return err;
236 		}
237 
238 		config->num_groups++;
239 	}
240 
241 	return 0;
242 }
243 
tegra_xusb_padctl_parse_dt(struct tegra_xusb_padctl * padctl,ofnode node)244 static int tegra_xusb_padctl_parse_dt(struct tegra_xusb_padctl *padctl,
245 				      ofnode node)
246 {
247 	ofnode subnode;
248 	int err;
249 
250 	err = ofnode_read_resource(node, 0, &padctl->regs);
251 	if (err < 0) {
252 		pr_err("registers not found");
253 		return err;
254 	}
255 
256 	ofnode_for_each_subnode(subnode, node) {
257 		struct tegra_xusb_padctl_config *config = &padctl->config;
258 
259 		debug("%s: subnode=%s\n", __func__, ofnode_get_name(subnode));
260 		err = tegra_xusb_padctl_config_parse_dt(padctl, config,
261 							subnode);
262 		if (err < 0) {
263 			pr_err("failed to parse entry %s: %d",
264 			      config->name, err);
265 			continue;
266 		}
267 	}
268 	debug("%s: done\n", __func__);
269 
270 	return 0;
271 }
272 
273 struct tegra_xusb_padctl padctl;
274 
tegra_xusb_process_nodes(ofnode nodes[],unsigned int count,const struct tegra_xusb_padctl_soc * socdata)275 int tegra_xusb_process_nodes(ofnode nodes[], unsigned int count,
276 			     const struct tegra_xusb_padctl_soc *socdata)
277 {
278 	unsigned int i;
279 	int err;
280 
281 	debug("%s: count=%d\n", __func__, count);
282 	for (i = 0; i < count; i++) {
283 		debug("%s: i=%d, node=%p\n", __func__, i, nodes[i].np);
284 		if (!ofnode_is_available(nodes[i]))
285 			continue;
286 
287 		padctl.socdata = socdata;
288 
289 		err = tegra_xusb_padctl_parse_dt(&padctl, nodes[i]);
290 		if (err < 0) {
291 			pr_err("failed to parse DT: %d", err);
292 			continue;
293 		}
294 
295 		/* deassert XUSB padctl reset */
296 		reset_set_enable(PERIPH_ID_XUSB_PADCTL, 0);
297 
298 		err = tegra_xusb_padctl_config_apply(&padctl, &padctl.config);
299 		if (err < 0) {
300 			pr_err("failed to apply pinmux: %d", err);
301 			continue;
302 		}
303 
304 		/* only a single instance is supported */
305 		break;
306 	}
307 	debug("%s: done\n", __func__);
308 
309 	return 0;
310 }
311