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 <bskeggs@redhat.com>
23 */
24#include <subdev/bios.h>
25#include <subdev/bios/bit.h>
26#include <subdev/bios/ramcfg.h>
27#include <subdev/bios/M0203.h>
28
29static u8
30nvbios_ramcfg_strap(struct nvkm_subdev *subdev)
31{
32	return (nvkm_rd32(subdev->device, 0x101000) & 0x0000003c) >> 2;
33}
34
35u8
36nvbios_ramcfg_count(struct nvkm_bios *bios)
37{
38	struct bit_entry bit_M;
39
40	if (!bit_entry(bios, 'M', &bit_M)) {
41		if (bit_M.version == 1 && bit_M.length >= 5)
42			return nvbios_rd08(bios, bit_M.offset + 2);
43		if (bit_M.version == 2 && bit_M.length >= 3)
44			return nvbios_rd08(bios, bit_M.offset + 0);
45	}
46
47	return 0x00;
48}
49
50u8
51nvbios_ramcfg_index(struct nvkm_subdev *subdev)
52{
53	struct nvkm_bios *bios = subdev->device->bios;
54	u8 strap = nvbios_ramcfg_strap(subdev);
55	u32 xlat = 0x00000000;
56	struct bit_entry bit_M;
57	struct nvbios_M0203E M0203E;
58	u8 ver, hdr;
59
60	if (!bit_entry(bios, 'M', &bit_M)) {
61		if (bit_M.version == 1 && bit_M.length >= 5)
62			xlat = nvbios_rd16(bios, bit_M.offset + 3);
63		if (bit_M.version == 2 && bit_M.length >= 3) {
64			/*XXX: is M ever shorter than this?
65			 *     if not - what is xlat used for now?
66			 *     also - sigh..
67			 */
68			if (bit_M.length >= 7 &&
69			    nvbios_M0203Em(bios, strap, &ver, &hdr, &M0203E))
70				return M0203E.group;
71			xlat = nvbios_rd16(bios, bit_M.offset + 1);
72		}
73	}
74
75	if (xlat)
76		strap = nvbios_rd08(bios, xlat + strap);
77	return strap;
78}
79