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 <subdev/volt.h>
25#include <subdev/bios.h>
26#include <subdev/bios/vmap.h>
27#include <subdev/bios/volt.h>
28
29static int
30nvkm_volt_get(struct nvkm_volt *volt)
31{
32	if (volt->vid_get) {
33		int ret = volt->vid_get(volt), i;
34		if (ret >= 0) {
35			for (i = 0; i < volt->vid_nr; i++) {
36				if (volt->vid[i].vid == ret)
37					return volt->vid[i].uv;
38			}
39			ret = -EINVAL;
40		}
41		return ret;
42	}
43	return -ENODEV;
44}
45
46static int
47nvkm_volt_set(struct nvkm_volt *volt, u32 uv)
48{
49	if (volt->vid_set) {
50		int i, ret = -EINVAL;
51		for (i = 0; i < volt->vid_nr; i++) {
52			if (volt->vid[i].uv == uv) {
53				ret = volt->vid_set(volt, volt->vid[i].vid);
54				nv_debug(volt, "set %duv: %d\n", uv, ret);
55				break;
56			}
57		}
58		return ret;
59	}
60	return -ENODEV;
61}
62
63static int
64nvkm_volt_map(struct nvkm_volt *volt, u8 id)
65{
66	struct nvkm_bios *bios = nvkm_bios(volt);
67	struct nvbios_vmap_entry info;
68	u8  ver, len;
69	u16 vmap;
70
71	vmap = nvbios_vmap_entry_parse(bios, id, &ver, &len, &info);
72	if (vmap) {
73		if (info.link != 0xff) {
74			int ret = nvkm_volt_map(volt, info.link);
75			if (ret < 0)
76				return ret;
77			info.min += ret;
78		}
79		return info.min;
80	}
81
82	return id ? id * 10000 : -ENODEV;
83}
84
85static int
86nvkm_volt_set_id(struct nvkm_volt *volt, u8 id, int condition)
87{
88	int ret = nvkm_volt_map(volt, id);
89	if (ret >= 0) {
90		int prev = nvkm_volt_get(volt);
91		if (!condition || prev < 0 ||
92		    (condition < 0 && ret < prev) ||
93		    (condition > 0 && ret > prev)) {
94			ret = nvkm_volt_set(volt, ret);
95		} else {
96			ret = 0;
97		}
98	}
99	return ret;
100}
101
102static void
103nvkm_volt_parse_bios(struct nvkm_bios *bios, struct nvkm_volt *volt)
104{
105	struct nvbios_volt_entry ivid;
106	struct nvbios_volt info;
107	u8  ver, hdr, cnt, len;
108	u16 data;
109	int i;
110
111	data = nvbios_volt_parse(bios, &ver, &hdr, &cnt, &len, &info);
112	if (data && info.vidmask && info.base && info.step) {
113		for (i = 0; i < info.vidmask + 1; i++) {
114			if (info.base >= info.min &&
115				info.base <= info.max) {
116				volt->vid[volt->vid_nr].uv = info.base;
117				volt->vid[volt->vid_nr].vid = i;
118				volt->vid_nr++;
119			}
120			info.base += info.step;
121		}
122		volt->vid_mask = info.vidmask;
123	} else if (data && info.vidmask) {
124		for (i = 0; i < cnt; i++) {
125			data = nvbios_volt_entry_parse(bios, i, &ver, &hdr,
126						       &ivid);
127			if (data) {
128				volt->vid[volt->vid_nr].uv = ivid.voltage;
129				volt->vid[volt->vid_nr].vid = ivid.vid;
130				volt->vid_nr++;
131			}
132		}
133		volt->vid_mask = info.vidmask;
134	}
135}
136
137int
138_nvkm_volt_init(struct nvkm_object *object)
139{
140	struct nvkm_volt *volt = (void *)object;
141	int ret;
142
143	ret = nvkm_subdev_init(&volt->base);
144	if (ret)
145		return ret;
146
147	ret = volt->get(volt);
148	if (ret < 0) {
149		if (ret != -ENODEV)
150			nv_debug(volt, "current voltage unknown\n");
151		return 0;
152	}
153
154	nv_info(volt, "GPU voltage: %duv\n", ret);
155	return 0;
156}
157
158void
159_nvkm_volt_dtor(struct nvkm_object *object)
160{
161	struct nvkm_volt *volt = (void *)object;
162	nvkm_subdev_destroy(&volt->base);
163}
164
165int
166nvkm_volt_create_(struct nvkm_object *parent, struct nvkm_object *engine,
167		  struct nvkm_oclass *oclass, int length, void **pobject)
168{
169	struct nvkm_bios *bios = nvkm_bios(parent);
170	struct nvkm_volt *volt;
171	int ret, i;
172
173	ret = nvkm_subdev_create_(parent, engine, oclass, 0, "VOLT",
174				  "voltage", length, pobject);
175	volt = *pobject;
176	if (ret)
177		return ret;
178
179	volt->get = nvkm_volt_get;
180	volt->set = nvkm_volt_set;
181	volt->set_id = nvkm_volt_set_id;
182
183	/* Assuming the non-bios device should build the voltage table later */
184	if (bios)
185		nvkm_volt_parse_bios(bios, volt);
186
187	if (volt->vid_nr) {
188		for (i = 0; i < volt->vid_nr; i++) {
189			nv_debug(volt, "VID %02x: %duv\n",
190				 volt->vid[i].vid, volt->vid[i].uv);
191		}
192
193		/*XXX: this is an assumption.. there probably exists boards
194		 * out there with i2c-connected voltage controllers too..
195		 */
196		ret = nvkm_voltgpio_init(volt);
197		if (ret == 0) {
198			volt->vid_get = nvkm_voltgpio_get;
199			volt->vid_set = nvkm_voltgpio_set;
200		}
201	}
202
203	return ret;
204}
205