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
28static u32
29nvbios_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
41int
42nvbios_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		if (h->hlen > 0x10)
62			h->boost_id = nvbios_rd08(b, h->offset + 0x10);
63		else
64			h->boost_id = 0xff;
65		if (h->hlen > 0x11)
66			h->tdp_id = nvbios_rd08(b, h->offset + 0x11);
67		else
68			h->tdp_id = 0xff;
69		return 0;
70	default:
71		return -EINVAL;
72	}
73}
74
75int
76nvbios_vpstate_entry(struct nvkm_bios *b, struct nvbios_vpstate_header *h,
77		     u8 idx, struct nvbios_vpstate_entry *e)
78{
79	u32 offset;
80
81	if (!e || !h || idx > h->ecount)
82		return -EINVAL;
83
84	offset = h->offset + h->hlen + idx * (h->elen + (h->slen * h->scount));
85	e->pstate    = nvbios_rd08(b, offset);
86	e->clock_mhz = nvbios_rd16(b, offset + 0x5);
87	return 0;
88}
89