kernel/drivers/gpu/drm/nouveau/nvkm/subdev/bios/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
  28 u16
  29 dcb_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 = nv_ro16(bios, dcb + 2);
  36                 if (*ver >= 0x30)
  37                         i2c = nv_ro16(bios, dcb + 4);
  38         }
  39
  40         if (i2c && *ver >= 0x42) {
  41                 nv_warn(bios, "ccb %02x not supported\n", *ver);
  42                 return 0x0000;
  43         }
  44
  45         if (i2c && *ver >= 0x30) {
  46                 *ver = nv_ro08(bios, i2c + 0);
  47                 *hdr = nv_ro08(bios, i2c + 1);
  48                 *cnt = nv_ro08(bios, i2c + 2);
  49                 *len = nv_ro08(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
  60 u16
  61 dcb_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
  70 int
  71 dcb_i2c_parse(struct nvkm_bios *bios, u8 idx, struct dcb_i2c_entry *info)
  72 {
  73         u8  ver, len;
  74         u16 ent = dcb_i2c_entry(bios, idx, &ver, &len);
  75         if (ent) {
  76                 if (ver >= 0x41) {
  77                         u32 ent_value = nv_ro32(bios, ent);
  78                         u8 i2c_port = (ent_value >> 27) & 0x1f;
  79                         u8 dpaux_port = (ent_value >> 22) & 0x1f;
  80                         /* value 0x1f means unused according to DCB 4.x spec */
  81                         if (i2c_port == 0x1f && dpaux_port == 0x1f)
  82                                 info->type = DCB_I2C_UNUSED;
  83                         else
  84                                 info->type = DCB_I2C_PMGR;
  85                 } else
  86                 if (ver >= 0x30) {
  87                         info->type = nv_ro08(bios, ent + 0x03);
  88                 } else {
  89                         info->type = nv_ro08(bios, ent + 0x03) & 0x07;
  90                         if (info->type == 0x07)
  91                                 info->type = DCB_I2C_UNUSED;
  92                 }
  93
  94                 info->drive = DCB_I2C_UNUSED;
  95                 info->sense = DCB_I2C_UNUSED;
  96                 info->share = DCB_I2C_UNUSED;
  97                 info->auxch = DCB_I2C_UNUSED;
  98
  99                 switch (info->type) {
 100                 case DCB_I2C_NV04_BIT:
 101                         info->drive = nv_ro08(bios, ent + 0);
 102                         info->sense = nv_ro08(bios, ent + 1);
 103                         return 0;
 104                 case DCB_I2C_NV4E_BIT:
 105                         info->drive = nv_ro08(bios, ent + 1);
 106                         return 0;
 107                 case DCB_I2C_NVIO_BIT:
 108                         info->drive = nv_ro08(bios, ent + 0) & 0x0f;
 109                         if (nv_ro08(bios, ent + 1) & 0x01)
 110                                 info->share = nv_ro08(bios, ent + 1) >> 1;
 111                         return 0;
 112                 case DCB_I2C_NVIO_AUX:
 113                         info->auxch = nv_ro08(bios, ent + 0) & 0x0f;
 114                         if (nv_ro08(bios, ent + 1) & 0x01)
 115                                         info->share = info->auxch;
 116                         return 0;
 117                 case DCB_I2C_PMGR:
 118                         info->drive = (nv_ro16(bios, ent + 0) & 0x01f) >> 0;
 119                         if (info->drive == 0x1f)
 120                                 info->drive = DCB_I2C_UNUSED;
 121                         info->auxch = (nv_ro16(bios, ent + 0) & 0x3e0) >> 5;
 122                         if (info->auxch == 0x1f)
 123                                 info->auxch = DCB_I2C_UNUSED;
 124                         info->share = info->auxch;
 125                         return 0;
 126                 case DCB_I2C_UNUSED:
 127                         return 0;
 128                 default:
 129                         nv_warn(bios, "unknown i2c type %d\n", info->type);
 130                         info->type = DCB_I2C_UNUSED;
 131                         return 0;
 132                 }
 133         }
 134
 135         if (bios->bmp_offset && idx < 2) {
 136                 /* BMP (from v4.0 has i2c info in the structure, it's in a
 137                  * fixed location on earlier VBIOS
 138                  */
 139                 if (nv_ro08(bios, bios->bmp_offset + 5) < 4)
 140                         ent = 0x0048;
 141                 else
 142                         ent = 0x0036 + bios->bmp_offset;
 143
 144                 if (idx == 0) {
 145                         info->drive = nv_ro08(bios, ent + 4);
 146                         if (!info->drive) info->drive = 0x3f;
 147                         info->sense = nv_ro08(bios, ent + 5);
 148                         if (!info->sense) info->sense = 0x3e;
 149                 } else
 150                 if (idx == 1) {
 151                         info->drive = nv_ro08(bios, ent + 6);
 152                         if (!info->drive) info->drive = 0x37;
 153                         info->sense = nv_ro08(bios, ent + 7);
 154                         if (!info->sense) info->sense = 0x36;
 155                 }
 156
 157                 info->type  = DCB_I2C_NV04_BIT;
 158                 info->share = DCB_I2C_UNUSED;
 159                 return 0;
 160         }
 161
 162         return -ENOENT;
 163 }