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  * 	    Roy Spliet <rspliet@eclipso.eu>
24  */
25 #include "ram.h"
26 
27 struct ramxlat {
28 	int id;
29 	u8 enc;
30 };
31 
32 static inline int
33 ramxlat(const struct ramxlat *xlat, int id)
34 {
35 	while (xlat->id >= 0) {
36 		if (xlat->id == id)
37 			return xlat->enc;
38 		xlat++;
39 	}
40 	return -EINVAL;
41 }
42 
43 static const struct ramxlat
44 ramgddr3_cl_lo[] = {
45 	{ 5, 5 }, { 7, 7 }, { 8, 0 }, { 9, 1 }, { 10, 2 }, { 11, 3 }, { 12, 8 },
46 	/* the below are mentioned in some, but not all, gddr3 docs */
47 	{ 13, 9 }, { 14, 6 },
48 	/* XXX: Per Samsung docs, are these used? They overlap with Qimonda */
49 	/* { 4, 4 }, { 5, 5 }, { 6, 6 }, { 12, 8 }, { 13, 9 }, { 14, 10 },
50 	 * { 15, 11 }, */
51 	{ -1 }
52 };
53 
54 static const struct ramxlat
55 ramgddr3_cl_hi[] = {
56 	{ 10, 2 }, { 11, 3 }, { 12, 4 }, { 13, 5 }, { 14, 6 }, { 15, 7 },
57 	{ 16, 0 }, { 17, 1 },
58 	{ -1 }
59 };
60 
61 static const struct ramxlat
62 ramgddr3_wr_lo[] = {
63 	{ 5, 2 }, { 7, 4 }, { 8, 5 }, { 9, 6 }, { 10, 7 },
64 	{ 11, 0 }, { 13 , 1 },
65 	/* the below are mentioned in some, but not all, gddr3 docs */
66 	{ 4, 0 }, { 6, 3 }, { 12, 1 },
67 	{ -1 }
68 };
69 
70 int
71 nvkm_gddr3_calc(struct nvkm_ram *ram)
72 {
73 	int CL, WR, CWL, DLL = 0, ODT = 0, RON, hi;
74 
75 	switch (ram->next->bios.timing_ver) {
76 	case 0x10:
77 		CWL = ram->next->bios.timing_10_CWL;
78 		CL  = ram->next->bios.timing_10_CL;
79 		WR  = ram->next->bios.timing_10_WR;
80 		DLL = !ram->next->bios.ramcfg_DLLoff;
81 		ODT = ram->next->bios.timing_10_ODT;
82 		RON = ram->next->bios.ramcfg_RON;
83 		break;
84 	case 0x20:
85 		CWL = (ram->next->bios.timing[1] & 0x00000f80) >> 7;
86 		CL  = (ram->next->bios.timing[1] & 0x0000001f) >> 0;
87 		WR  = (ram->next->bios.timing[2] & 0x007f0000) >> 16;
88 		/* XXX: Get these values from the VBIOS instead */
89 		DLL = !(ram->mr[1] & 0x1);
90 		RON = !((ram->mr[1] & 0x300) >> 8);
91 		break;
92 	default:
93 		return -ENOSYS;
94 	}
95 
96 	if (ram->next->bios.timing_ver == 0x20 ||
97 	    ram->next->bios.ramcfg_timing == 0xff) {
98 		ODT =  (ram->mr[1] & 0xc) >> 2;
99 	}
100 
101 	hi = ram->mr[2] & 0x1;
102 	CL  = ramxlat(hi ? ramgddr3_cl_hi : ramgddr3_cl_lo, CL);
103 	WR  = ramxlat(ramgddr3_wr_lo, WR);
104 	if (CL < 0 || CWL < 1 || CWL > 7 || WR < 0)
105 		return -EINVAL;
106 
107 	ram->mr[0] &= ~0xf74;
108 	ram->mr[0] |= (CWL & 0x07) << 9;
109 	ram->mr[0] |= (CL & 0x07) << 4;
110 	ram->mr[0] |= (CL & 0x08) >> 1;
111 
112 	ram->mr[1] &= ~0x3fc;
113 	ram->mr[1] |= (ODT & 0x03) << 2;
114 	ram->mr[1] |= (RON & 0x03) << 8;
115 	ram->mr[1] |= (WR  & 0x03) << 4;
116 	ram->mr[1] |= (WR  & 0x04) << 5;
117 	ram->mr[1] |= !DLL << 6;
118 	return 0;
119 }
120