i2c.c

  1/*
  2 * Copyright 2012 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
 23 */
 24#include <subdev/bios.h>
 25#include <subdev/bios/dcb.h>
 26#include <subdev/bios/i2c.h>
 27
 28u16
 29dcb_i2c_table(struct nvkm_bios *bios, u8 *ver, u8 *hdr, u8 *cnt, u8 *len)
 30{
 31	u16 i2c = 0x0000;
 32	u16 dcb = dcb_table(bios, ver, hdr, cnt, len);
 33	if (dcb) {
 34		if (*ver >= 0x15)
 35			i2c = nvbios_rd16(bios, dcb + 2);
 36		if (*ver >= 0x30)
 37			i2c = nvbios_rd16(bios, dcb + 4);
 38	}
 39
 40	if (i2c && *ver >= 0x42) {
 41		nvkm_warn(&bios->subdev, "ccb %02x not supported\n", *ver);
 42		return 0x0000;
 43	}
 44
 45	if (i2c && *ver >= 0x30) {
 46		*ver = nvbios_rd08(bios, i2c + 0);
 47		*hdr = nvbios_rd08(bios, i2c + 1);
 48		*cnt = nvbios_rd08(bios, i2c + 2);
 49		*len = nvbios_rd08(bios, i2c + 3);
 50	} else {
 51		*ver = *ver; /* use DCB version */
 52		*hdr = 0;
 53		*cnt = 16;
 54		*len = 4;
 55	}
 56
 57	return i2c;
 58}
 59
 60u16
 61dcb_i2c_entry(struct nvkm_bios *bios, u8 idx, u8 *ver, u8 *len)
 62{
 63	u8  hdr, cnt;
 64	u16 i2c = dcb_i2c_table(bios, ver, &hdr, &cnt, len);
 65	if (i2c && idx < cnt)
 66		return i2c + hdr + (idx * *len);
 67	return 0x0000;
 68}
 69
 70int
 71dcb_i2c_parse(struct nvkm_bios *bios, u8 idx, struct dcb_i2c_entry *info)
 72{
 73	struct nvkm_subdev *subdev = &bios->subdev;
 74	u8  ver, len;
 75	u16 ent = dcb_i2c_entry(bios, idx, &ver, &len);
 76	if (ent) {
 77		if (ver >= 0x41) {
 78			u32 ent_value = nvbios_rd32(bios, ent);
 79			u8 i2c_port = (ent_value >> 0) & 0x1f;
 80			u8 dpaux_port = (ent_value >> 5) & 0x1f;
 81			/* value 0x1f means unused according to DCB 4.x spec */
 82			if (i2c_port == 0x1f && dpaux_port == 0x1f)
 83				info->type = DCB_I2C_UNUSED;
 84			else
 85				info->type = DCB_I2C_PMGR;
 86		} else
 87		if (ver >= 0x30) {
 88			info->type = nvbios_rd08(bios, ent + 0x03);
 89		} else {
 90			info->type = nvbios_rd08(bios, ent + 0x03) & 0x07;
 91			if (info->type == 0x07)
 92				info->type = DCB_I2C_UNUSED;
 93		}
 94
 95		info->drive = DCB_I2C_UNUSED;
 96		info->sense = DCB_I2C_UNUSED;
 97		info->share = DCB_I2C_UNUSED;
 98		info->auxch = DCB_I2C_UNUSED;
 99
100		switch (info->type) {
101		case DCB_I2C_NV04_BIT:
102			info->drive = nvbios_rd08(bios, ent + 0);
103			info->sense = nvbios_rd08(bios, ent + 1);
104			return 0;
105		case DCB_I2C_NV4E_BIT:
106			info->drive = nvbios_rd08(bios, ent + 1);
107			return 0;
108		case DCB_I2C_NVIO_BIT:
109			info->drive = nvbios_rd08(bios, ent + 0) & 0x0f;
110			if (nvbios_rd08(bios, ent + 1) & 0x01)
111				info->share = nvbios_rd08(bios, ent + 1) >> 1;
112			return 0;
113		case DCB_I2C_NVIO_AUX:
114			info->auxch = nvbios_rd08(bios, ent + 0) & 0x0f;
115			if (nvbios_rd08(bios, ent + 1) & 0x01)
116					info->share = info->auxch;
117			return 0;
118		case DCB_I2C_PMGR:
119			info->drive = (nvbios_rd16(bios, ent + 0) & 0x01f) >> 0;
120			if (info->drive == 0x1f)
121				info->drive = DCB_I2C_UNUSED;
122			info->auxch = (nvbios_rd16(bios, ent + 0) & 0x3e0) >> 5;
123			if (info->auxch == 0x1f)
124				info->auxch = DCB_I2C_UNUSED;
125			info->share = info->auxch;
126			return 0;
127		case DCB_I2C_UNUSED:
128			return 0;
129		default:
130			nvkm_warn(subdev, "unknown i2c type %d\n", info->type);
131			info->type = DCB_I2C_UNUSED;
132			return 0;
133		}
134	}
135
136	if (bios->bmp_offset && idx < 2) {
137		/* BMP (from v4.0 has i2c info in the structure, it's in a
138		 * fixed location on earlier VBIOS
139		 */
140		if (nvbios_rd08(bios, bios->bmp_offset + 5) < 4)
141			ent = 0x0048;
142		else
143			ent = 0x0036 + bios->bmp_offset;
144
145		if (idx == 0) {
146			info->drive = nvbios_rd08(bios, ent + 4);
147			if (!info->drive) info->drive = 0x3f;
148			info->sense = nvbios_rd08(bios, ent + 5);
149			if (!info->sense) info->sense = 0x3e;
150		} else
151		if (idx == 1) {
152			info->drive = nvbios_rd08(bios, ent + 6);
153			if (!info->drive) info->drive = 0x37;
154			info->sense = nvbios_rd08(bios, ent + 7);
155			if (!info->sense) info->sense = 0x36;
156		}
157
158		info->type  = DCB_I2C_NV04_BIT;
159		info->share = DCB_I2C_UNUSED;
160		return 0;
161	}
162
163	return -ENOENT;
164}