drivers/gpu/drm/amd/powerplay/hwmgr/pppcielanes.c

   1 /*
   2  * Copyright 2015 Advanced Micro Devices, 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  */
  23
  24 #include <linux/types.h>
  25 #include "atom-types.h"
  26 #include "atombios.h"
  27 #include "pppcielanes.h"
  28
  29 /** \file
  30  * Functions related to PCIe lane changes.
  31  */
  32
  33 /* For converting from number of lanes to lane bits.  */
  34 static const unsigned char pp_r600_encode_lanes[] = {
  35         0,          /*  0 Not Supported  */
  36         1,          /*  1 Lane  */
  37         2,          /*  2 Lanes  */
  38         0,          /*  3 Not Supported  */
  39         3,          /*  4 Lanes  */
  40         0,          /*  5 Not Supported  */
  41         0,          /*  6 Not Supported  */
  42         0,          /*  7 Not Supported  */
  43         4,          /*  8 Lanes  */
  44         0,          /*  9 Not Supported  */
  45         0,          /* 10 Not Supported  */
  46         0,          /* 11 Not Supported  */
  47         5,          /* 12 Lanes (Not actually supported)  */
  48         0,          /* 13 Not Supported  */
  49         0,          /* 14 Not Supported  */
  50         0,          /* 15 Not Supported  */
  51         6           /* 16 Lanes  */
  52 };
  53
  54 static const unsigned char pp_r600_decoded_lanes[8] = { 16, 1, 2, 4, 8, 12, 16, };
  55
  56 uint8_t encode_pcie_lane_width(uint32_t num_lanes)
  57 {
  58         return pp_r600_encode_lanes[num_lanes];
  59 }
  60
  61 uint8_t decode_pcie_lane_width(uint32_t num_lanes)
  62 {
  63         return pp_r600_decoded_lanes[num_lanes];
  64 }