drivers/gpu/drm/nouveau/nvkm/subdev/bios/iccsense.c

   1 /*
   2  * Copyright 2015 Martin Peres
   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: Martin Peres
  23  */
  24 #include <subdev/bios.h>
  25 #include <subdev/bios/bit.h>
  26 #include <subdev/bios/iccsense.h>
  27
  28 static u16
  29 nvbios_iccsense_table(struct nvkm_bios *bios, u8 *ver, u8 *hdr, u8 *cnt,
  30                       u8 *len)
  31 {
  32         struct bit_entry bit_P;
  33         u16 iccsense;
  34
  35         if (bit_entry(bios, 'P', &bit_P) || bit_P.version != 2 ||
  36             bit_P.length < 0x2c)
  37                 return 0;
  38
  39         iccsense = nvbios_rd16(bios, bit_P.offset + 0x28);
  40         if (!iccsense)
  41                 return 0;
  42
  43         *ver = nvbios_rd08(bios, iccsense + 0);
  44         switch (*ver) {
  45         case 0x10:
  46         case 0x20:
  47                 *hdr = nvbios_rd08(bios, iccsense + 1);
  48                 *len = nvbios_rd08(bios, iccsense + 2);
  49                 *cnt = nvbios_rd08(bios, iccsense + 3);
  50                 return iccsense;
  51         default:
  52                 break;
  53         }
  54
  55         return 0;
  56 }
  57
  58 int
  59 nvbios_iccsense_parse(struct nvkm_bios *bios, struct nvbios_iccsense *iccsense)
  60 {
  61         struct nvkm_subdev *subdev = &bios->subdev;
  62         u8 ver, hdr, cnt, len, i;
  63         u16 table, entry;
  64
  65         table = nvbios_iccsense_table(bios, &ver, &hdr, &cnt, &len);
  66         if (!table || !cnt)
  67                 return -EINVAL;
  68
  69         if (ver != 0x10 && ver != 0x20) {
  70                 nvkm_error(subdev, "ICCSENSE version 0x%02x unknown\n", ver);
  71                 return -EINVAL;
  72         }
  73
  74         iccsense->nr_entry = cnt;
  75         iccsense->rail = kmalloc(sizeof(struct pwr_rail_t) * cnt, GFP_KERNEL);
  76         if (!iccsense->rail)
  77                 return -ENOMEM;
  78
  79         for (i = 0; i < cnt; ++i) {
  80                 struct pwr_rail_t *rail = &iccsense->rail[i];
  81                 entry = table + hdr + i * len;
  82
  83                 switch(ver) {
  84                 case 0x10:
  85                         rail->mode = nvbios_rd08(bios, entry + 0x1);
  86                         rail->extdev_id = nvbios_rd08(bios, entry + 0x2);
  87                         rail->resistor_mohm = nvbios_rd08(bios, entry + 0x3);
  88                         rail->rail = nvbios_rd08(bios, entry + 0x4);
  89                         break;
  90                 case 0x20:
  91                         rail->mode = nvbios_rd08(bios, entry);
  92                         rail->extdev_id = nvbios_rd08(bios, entry + 0x1);
  93                         rail->resistor_mohm = nvbios_rd08(bios, entry + 0x5);
  94                         rail->rail = nvbios_rd08(bios, entry + 0x6);
  95                         break;
  96                 };
  97         }
  98
  99         return 0;
 100 }