xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/nouveau/nvkm/subdev/bios/nouveau_nvkm_subdev_bios_i2c.c (revision 41ec02673d281bbb3d38e6c78504ce6e30c228c1)
1 /*	$NetBSD: nouveau_nvkm_subdev_bios_i2c.c,v 1.3 2021/12/18 23:45:38 riastradh Exp $	*/
2 
3 /*
4  * Copyright 2012 Red Hat Inc.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22  * OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * Authors: Ben Skeggs
25  */
26 #include <sys/cdefs.h>
27 __KERNEL_RCSID(0, "$NetBSD: nouveau_nvkm_subdev_bios_i2c.c,v 1.3 2021/12/18 23:45:38 riastradh Exp $");
28 
29 #include <subdev/bios.h>
30 #include <subdev/bios/dcb.h>
31 #include <subdev/bios/i2c.h>
32 
33 u16
dcb_i2c_table(struct nvkm_bios * bios,u8 * ver,u8 * hdr,u8 * cnt,u8 * len)34 dcb_i2c_table(struct nvkm_bios *bios, u8 *ver, u8 *hdr, u8 *cnt, u8 *len)
35 {
36 	u16 i2c = 0x0000;
37 	u16 dcb = dcb_table(bios, ver, hdr, cnt, len);
38 	if (dcb) {
39 		if (*ver >= 0x15)
40 			i2c = nvbios_rd16(bios, dcb + 2);
41 		if (*ver >= 0x30)
42 			i2c = nvbios_rd16(bios, dcb + 4);
43 	}
44 
45 	if (i2c && *ver >= 0x42) {
46 		nvkm_warn(&bios->subdev, "ccb %02x not supported\n", *ver);
47 		return 0x0000;
48 	}
49 
50 	if (i2c && *ver >= 0x30) {
51 		*ver = nvbios_rd08(bios, i2c + 0);
52 		*hdr = nvbios_rd08(bios, i2c + 1);
53 		*cnt = nvbios_rd08(bios, i2c + 2);
54 		*len = nvbios_rd08(bios, i2c + 3);
55 	} else {
56 		*ver = *ver; /* use DCB version */
57 		*hdr = 0;
58 		*cnt = 16;
59 		*len = 4;
60 	}
61 
62 	return i2c;
63 }
64 
65 u16
dcb_i2c_entry(struct nvkm_bios * bios,u8 idx,u8 * ver,u8 * len)66 dcb_i2c_entry(struct nvkm_bios *bios, u8 idx, u8 *ver, u8 *len)
67 {
68 	u8  hdr, cnt;
69 	u16 i2c = dcb_i2c_table(bios, ver, &hdr, &cnt, len);
70 	if (i2c && idx < cnt)
71 		return i2c + hdr + (idx * *len);
72 	return 0x0000;
73 }
74 
75 int
dcb_i2c_parse(struct nvkm_bios * bios,u8 idx,struct dcb_i2c_entry * info)76 dcb_i2c_parse(struct nvkm_bios *bios, u8 idx, struct dcb_i2c_entry *info)
77 {
78 	struct nvkm_subdev *subdev = &bios->subdev;
79 	u8  ver, len;
80 	u16 ent = dcb_i2c_entry(bios, idx, &ver, &len);
81 	if (ent) {
82 		if (ver >= 0x41) {
83 			u32 ent_value = nvbios_rd32(bios, ent);
84 			u8 i2c_port = (ent_value >> 0) & 0x1f;
85 			u8 dpaux_port = (ent_value >> 5) & 0x1f;
86 			/* value 0x1f means unused according to DCB 4.x spec */
87 			if (i2c_port == 0x1f && dpaux_port == 0x1f)
88 				info->type = DCB_I2C_UNUSED;
89 			else
90 				info->type = DCB_I2C_PMGR;
91 		} else
92 		if (ver >= 0x30) {
93 			info->type = nvbios_rd08(bios, ent + 0x03);
94 		} else {
95 			info->type = nvbios_rd08(bios, ent + 0x03) & 0x07;
96 			if (info->type == 0x07)
97 				info->type = DCB_I2C_UNUSED;
98 		}
99 
100 		info->drive = DCB_I2C_UNUSED;
101 		info->sense = DCB_I2C_UNUSED;
102 		info->share = DCB_I2C_UNUSED;
103 		info->auxch = DCB_I2C_UNUSED;
104 
105 		switch (info->type) {
106 		case DCB_I2C_NV04_BIT:
107 			info->drive = nvbios_rd08(bios, ent + 0);
108 			info->sense = nvbios_rd08(bios, ent + 1);
109 			return 0;
110 		case DCB_I2C_NV4E_BIT:
111 			info->drive = nvbios_rd08(bios, ent + 1);
112 			return 0;
113 		case DCB_I2C_NVIO_BIT:
114 			info->drive = nvbios_rd08(bios, ent + 0) & 0x0f;
115 			if (nvbios_rd08(bios, ent + 1) & 0x01)
116 				info->share = nvbios_rd08(bios, ent + 1) >> 1;
117 			return 0;
118 		case DCB_I2C_NVIO_AUX:
119 			info->auxch = nvbios_rd08(bios, ent + 0) & 0x0f;
120 			if (nvbios_rd08(bios, ent + 1) & 0x01)
121 					info->share = info->auxch;
122 			return 0;
123 		case DCB_I2C_PMGR:
124 			info->drive = (nvbios_rd16(bios, ent + 0) & 0x01f) >> 0;
125 			if (info->drive == 0x1f)
126 				info->drive = DCB_I2C_UNUSED;
127 			info->auxch = (nvbios_rd16(bios, ent + 0) & 0x3e0) >> 5;
128 			if (info->auxch == 0x1f)
129 				info->auxch = DCB_I2C_UNUSED;
130 			info->share = info->auxch;
131 			return 0;
132 		case DCB_I2C_UNUSED:
133 			return 0;
134 		default:
135 			nvkm_warn(subdev, "unknown i2c type %d\n", info->type);
136 			info->type = DCB_I2C_UNUSED;
137 			return 0;
138 		}
139 	}
140 
141 	if (bios->bmp_offset && idx < 2) {
142 		/* BMP (from v4.0 has i2c info in the structure, it's in a
143 		 * fixed location on earlier VBIOS
144 		 */
145 		if (nvbios_rd08(bios, bios->bmp_offset + 5) < 4)
146 			ent = 0x0048;
147 		else
148 			ent = 0x0036 + bios->bmp_offset;
149 
150 		if (idx == 0) {
151 			info->drive = nvbios_rd08(bios, ent + 4);
152 			if (!info->drive) info->drive = 0x3f;
153 			info->sense = nvbios_rd08(bios, ent + 5);
154 			if (!info->sense) info->sense = 0x3e;
155 		} else
156 		if (idx == 1) {
157 			info->drive = nvbios_rd08(bios, ent + 6);
158 			if (!info->drive) info->drive = 0x37;
159 			info->sense = nvbios_rd08(bios, ent + 7);
160 			if (!info->sense) info->sense = 0x36;
161 		}
162 
163 		info->type  = DCB_I2C_NV04_BIT;
164 		info->share = DCB_I2C_UNUSED;
165 		return 0;
166 	}
167 
168 	return -ENOENT;
169 }
170