1 /*
2  * Copyright 2016 Karol Herbst
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: Karol Herbst
23  */
24 #include <subdev/bios.h>
25 #include <subdev/bios/bit.h>
26 #include <subdev/bios/vpstate.h>
27 
28 static u32
29 nvbios_vpstate_offset(struct nvkm_bios *b)
30 {
31 	struct bit_entry bit_P;
32 
33 	if (!bit_entry(b, 'P', &bit_P)) {
34 		if (bit_P.version == 2 && bit_P.length >= 0x3c)
35 			return nvbios_rd32(b, bit_P.offset + 0x38);
36 	}
37 
38 	return 0x0000;
39 }
40 
41 int
42 nvbios_vpstate_parse(struct nvkm_bios *b, struct nvbios_vpstate_header *h)
43 {
44 	if (!h)
45 		return -EINVAL;
46 
47 	h->offset = nvbios_vpstate_offset(b);
48 	if (!h->offset)
49 		return -ENODEV;
50 
51 	h->version = nvbios_rd08(b, h->offset);
52 	switch (h->version) {
53 	case 0x10:
54 		h->hlen     = nvbios_rd08(b, h->offset + 0x1);
55 		h->elen     = nvbios_rd08(b, h->offset + 0x2);
56 		h->slen     = nvbios_rd08(b, h->offset + 0x3);
57 		h->scount   = nvbios_rd08(b, h->offset + 0x4);
58 		h->ecount   = nvbios_rd08(b, h->offset + 0x5);
59 
60 		h->base_id  = nvbios_rd08(b, h->offset + 0x0f);
61 		h->boost_id = nvbios_rd08(b, h->offset + 0x10);
62 		h->tdp_id   = nvbios_rd08(b, h->offset + 0x11);
63 		return 0;
64 	default:
65 		return -EINVAL;
66 	}
67 }
68 
69 int
70 nvbios_vpstate_entry(struct nvkm_bios *b, struct nvbios_vpstate_header *h,
71 		     u8 idx, struct nvbios_vpstate_entry *e)
72 {
73 	u32 offset;
74 
75 	if (!e || !h || idx > h->ecount)
76 		return -EINVAL;
77 
78 	offset = h->offset + h->hlen + idx * (h->elen + (h->slen * h->scount));
79 	e->pstate    = nvbios_rd08(b, offset);
80 	e->clock_mhz = nvbios_rd16(b, offset + 0x5);
81 	return 0;
82 }
83