1 /*
2  * Copyright 2013 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Ben Skeggs
23  */
24 #include "priv.h"
25 
26 #include <subdev/bios.h>
27 #include <subdev/bios/vmap.h>
28 #include <subdev/bios/volt.h>
29 
30 int
31 nvkm_volt_get(struct nvkm_volt *volt)
32 {
33 	int ret, i;
34 
35 	if (volt->func->volt_get)
36 		return volt->func->volt_get(volt);
37 
38 	ret = volt->func->vid_get(volt);
39 	if (ret >= 0) {
40 		for (i = 0; i < volt->vid_nr; i++) {
41 			if (volt->vid[i].vid == ret)
42 				return volt->vid[i].uv;
43 		}
44 		ret = -EINVAL;
45 	}
46 	return ret;
47 }
48 
49 static int
50 nvkm_volt_set(struct nvkm_volt *volt, u32 uv)
51 {
52 	struct nvkm_subdev *subdev = &volt->subdev;
53 	int i, ret = -EINVAL;
54 
55 	if (volt->func->volt_set)
56 		return volt->func->volt_set(volt, uv);
57 
58 	for (i = 0; i < volt->vid_nr; i++) {
59 		if (volt->vid[i].uv == uv) {
60 			ret = volt->func->vid_set(volt, volt->vid[i].vid);
61 			nvkm_debug(subdev, "set %duv: %d\n", uv, ret);
62 			break;
63 		}
64 	}
65 	return ret;
66 }
67 
68 static int
69 nvkm_volt_map(struct nvkm_volt *volt, u8 id)
70 {
71 	struct nvkm_bios *bios = volt->subdev.device->bios;
72 	struct nvbios_vmap_entry info;
73 	u8  ver, len;
74 	u16 vmap;
75 
76 	vmap = nvbios_vmap_entry_parse(bios, id, &ver, &len, &info);
77 	if (vmap) {
78 		if (info.link != 0xff) {
79 			int ret = nvkm_volt_map(volt, info.link);
80 			if (ret < 0)
81 				return ret;
82 			info.min += ret;
83 		}
84 		return info.min;
85 	}
86 
87 	return id ? id * 10000 : -ENODEV;
88 }
89 
90 int
91 nvkm_volt_set_id(struct nvkm_volt *volt, u8 id, int condition)
92 {
93 	int ret;
94 
95 	if (volt->func->set_id)
96 		return volt->func->set_id(volt, id, condition);
97 
98 	ret = nvkm_volt_map(volt, id);
99 	if (ret >= 0) {
100 		int prev = nvkm_volt_get(volt);
101 		if (!condition || prev < 0 ||
102 		    (condition < 0 && ret < prev) ||
103 		    (condition > 0 && ret > prev)) {
104 			ret = nvkm_volt_set(volt, ret);
105 		} else {
106 			ret = 0;
107 		}
108 	}
109 	return ret;
110 }
111 
112 static void
113 nvkm_volt_parse_bios(struct nvkm_bios *bios, struct nvkm_volt *volt)
114 {
115 	struct nvbios_volt_entry ivid;
116 	struct nvbios_volt info;
117 	u8  ver, hdr, cnt, len;
118 	u16 data;
119 	int i;
120 
121 	data = nvbios_volt_parse(bios, &ver, &hdr, &cnt, &len, &info);
122 	if (data && info.vidmask && info.base && info.step) {
123 		volt->min_uv = info.min;
124 		volt->max_uv = info.max;
125 		for (i = 0; i < info.vidmask + 1; i++) {
126 			if (info.base >= info.min &&
127 				info.base <= info.max) {
128 				volt->vid[volt->vid_nr].uv = info.base;
129 				volt->vid[volt->vid_nr].vid = i;
130 				volt->vid_nr++;
131 			}
132 			info.base += info.step;
133 		}
134 		volt->vid_mask = info.vidmask;
135 	} else if (data && info.vidmask) {
136 		volt->min_uv = 0xffffffff;
137 		volt->max_uv = 0;
138 		for (i = 0; i < cnt; i++) {
139 			data = nvbios_volt_entry_parse(bios, i, &ver, &hdr,
140 						       &ivid);
141 			if (data) {
142 				volt->vid[volt->vid_nr].uv = ivid.voltage;
143 				volt->vid[volt->vid_nr].vid = ivid.vid;
144 				volt->vid_nr++;
145 				volt->min_uv = min(volt->min_uv, ivid.voltage);
146 				volt->max_uv = max(volt->max_uv, ivid.voltage);
147 			}
148 		}
149 		volt->vid_mask = info.vidmask;
150 	} else if (data && info.type == NVBIOS_VOLT_PWM) {
151 		volt->min_uv = info.base;
152 		volt->max_uv = info.base + info.pwm_range;
153 	}
154 }
155 
156 static int
157 nvkm_volt_init(struct nvkm_subdev *subdev)
158 {
159 	struct nvkm_volt *volt = nvkm_volt(subdev);
160 	int ret = nvkm_volt_get(volt);
161 	if (ret < 0) {
162 		if (ret != -ENODEV)
163 			nvkm_debug(subdev, "current voltage unknown\n");
164 		return 0;
165 	}
166 	nvkm_debug(subdev, "current voltage: %duv\n", ret);
167 	return 0;
168 }
169 
170 static void *
171 nvkm_volt_dtor(struct nvkm_subdev *subdev)
172 {
173 	return nvkm_volt(subdev);
174 }
175 
176 static const struct nvkm_subdev_func
177 nvkm_volt = {
178 	.dtor = nvkm_volt_dtor,
179 	.init = nvkm_volt_init,
180 };
181 
182 void
183 nvkm_volt_ctor(const struct nvkm_volt_func *func, struct nvkm_device *device,
184 	       int index, struct nvkm_volt *volt)
185 {
186 	struct nvkm_bios *bios = device->bios;
187 	int i;
188 
189 	nvkm_subdev_ctor(&nvkm_volt, device, index, &volt->subdev);
190 	volt->func = func;
191 
192 	/* Assuming the non-bios device should build the voltage table later */
193 	if (bios) {
194 		nvkm_volt_parse_bios(bios, volt);
195 		nvkm_debug(&volt->subdev, "min: %iuv max: %iuv\n",
196 			   volt->min_uv, volt->max_uv);
197 	}
198 
199 	if (volt->vid_nr) {
200 		for (i = 0; i < volt->vid_nr; i++) {
201 			nvkm_debug(&volt->subdev, "VID %02x: %duv\n",
202 				   volt->vid[i].vid, volt->vid[i].uv);
203 		}
204 	}
205 }
206 
207 int
208 nvkm_volt_new_(const struct nvkm_volt_func *func, struct nvkm_device *device,
209 	       int index, struct nvkm_volt **pvolt)
210 {
211 	if (!(*pvolt = kzalloc(sizeof(**pvolt), GFP_KERNEL)))
212 		return -ENOMEM;
213 	nvkm_volt_ctor(func, device, index, *pvolt);
214 	return 0;
215 }
216