drivers/gpu/drm/nouveau/core/subdev/bios/dcb.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
  25 #include "core/device.h"
  26
  27 #include "subdev/bios.h"
  28 #include "subdev/bios/dcb.h"
  29
  30 u16
  31 dcb_table(struct nouveau_bios *bios, u8 *ver, u8 *hdr, u8 *cnt, u8 *len)
  32 {
  33         struct nouveau_device *device = nv_device(bios);
  34         u16 dcb = 0x0000;
  35
  36         if (device->card_type > NV_04)
  37                 dcb = nv_ro16(bios, 0x36);
  38         if (!dcb) {
  39                 nv_warn(bios, "DCB table not found\n");
  40                 return dcb;
  41         }
  42
  43         *ver = nv_ro08(bios, dcb);
  44
  45         if (*ver >= 0x41) {
  46                 nv_warn(bios, "DCB version 0x%02x unknown\n", *ver);
  47                 return 0x0000;
  48         } else
  49         if (*ver >= 0x30) {
  50                 if (nv_ro32(bios, dcb + 6) == 0x4edcbdcb) {
  51                         *hdr = nv_ro08(bios, dcb + 1);
  52                         *cnt = nv_ro08(bios, dcb + 2);
  53                         *len = nv_ro08(bios, dcb + 3);
  54                         return dcb;
  55                 }
  56         } else
  57         if (*ver >= 0x20) {
  58                 if (nv_ro32(bios, dcb + 4) == 0x4edcbdcb) {
  59                         u16 i2c = nv_ro16(bios, dcb + 2);
  60                         *hdr = 8;
  61                         *cnt = (i2c - dcb) / 8;
  62                         *len = 8;
  63                         return dcb;
  64                 }
  65         } else
  66         if (*ver >= 0x15) {
  67                 if (!nv_memcmp(bios, dcb - 7, "DEV_REC", 7)) {
  68                         u16 i2c = nv_ro16(bios, dcb + 2);
  69                         *hdr = 4;
  70                         *cnt = (i2c - dcb) / 10;
  71                         *len = 10;
  72                         return dcb;
  73                 }
  74         } else {
  75                 /*
  76                  * v1.4 (some NV15/16, NV11+) seems the same as v1.5, but
  77                  * always has the same single (crt) entry, even when tv-out
  78                  * present, so the conclusion is this version cannot really
  79                  * be used.
  80                  *
  81                  * v1.2 tables (some NV6/10, and NV15+) normally have the
  82                  * same 5 entries, which are not specific to the card and so
  83                  * no use.
  84                  *
  85                  * v1.2 does have an I2C table that read_dcb_i2c_table can
  86                  * handle, but cards exist (nv11 in #14821) with a bad i2c
  87                  * table pointer, so use the indices parsed in
  88                  * parse_bmp_structure.
  89                  *
  90                  * v1.1 (NV5+, maybe some NV4) is entirely unhelpful
  91                  */
  92                 nv_warn(bios, "DCB contains no useful data\n");
  93                 return 0x0000;
  94         }
  95
  96         nv_warn(bios, "DCB header validation failed\n");
  97         return 0x0000;
  98 }
  99
 100 u16
 101 dcb_outp(struct nouveau_bios *bios, u8 idx, u8 *ver, u8 *len)
 102 {
 103         u8  hdr, cnt;
 104         u16 dcb = dcb_table(bios, ver, &hdr, &cnt, len);
 105         if (dcb && idx < cnt)
 106                 return dcb + hdr + (idx * *len);
 107         return 0x0000;
 108 }
 109
 110 int
 111 dcb_outp_foreach(struct nouveau_bios *bios, void *data,
 112                  int (*exec)(struct nouveau_bios *, void *, int, u16))
 113 {
 114         int ret, idx = -1;
 115         u8  ver, len;
 116         u16 outp;
 117
 118         while ((outp = dcb_outp(bios, ++idx, &ver, &len))) {
 119                 if (nv_ro32(bios, outp) == 0x00000000)
 120                         break; /* seen on an NV11 with DCB v1.5 */
 121                 if (nv_ro32(bios, outp) == 0xffffffff)
 122                         break; /* seen on an NV17 with DCB v2.0 */
 123
 124                 if (nv_ro08(bios, outp) == DCB_OUTPUT_UNUSED)
 125                         continue;
 126                 if (nv_ro08(bios, outp) == DCB_OUTPUT_EOL)
 127                         break;
 128
 129                 ret = exec(bios, data, idx, outp);
 130                 if (ret)
 131                         return ret;
 132         }
 133
 134         return 0;
 135 }