drivers/gpu/drm/nouveau/nvkm/subdev/ibus/gk20a.c

   1 /*
   2  * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
   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 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  19  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  20  * DEALINGS IN THE SOFTWARE.
  21  */
  22 #include <subdev/ibus.h>
  23 #include <subdev/timer.h>
  24
  25 static void
  26 gk20a_ibus_init_ibus_ring(struct nvkm_subdev *ibus)
  27 {
  28         struct nvkm_device *device = ibus->device;
  29         nvkm_mask(device, 0x137250, 0x3f, 0);
  30
  31         nvkm_mask(device, 0x000200, 0x20, 0);
  32         udelay(20);
  33         nvkm_mask(device, 0x000200, 0x20, 0x20);
  34
  35         nvkm_wr32(device, 0x12004c, 0x4);
  36         nvkm_wr32(device, 0x122204, 0x2);
  37         nvkm_rd32(device, 0x122204);
  38
  39         /*
  40          * Bug: increase clock timeout to avoid operation failure at high
  41          * gpcclk rate.
  42          */
  43         nvkm_wr32(device, 0x122354, 0x800);
  44         nvkm_wr32(device, 0x128328, 0x800);
  45         nvkm_wr32(device, 0x124320, 0x800);
  46 }
  47
  48 static void
  49 gk20a_ibus_intr(struct nvkm_subdev *ibus)
  50 {
  51         struct nvkm_device *device = ibus->device;
  52         u32 status0 = nvkm_rd32(device, 0x120058);
  53
  54         if (status0 & 0x7) {
  55                 nvkm_debug(ibus, "resetting ibus ring\n");
  56                 gk20a_ibus_init_ibus_ring(ibus);
  57         }
  58
  59         /* Acknowledge interrupt */
  60         nvkm_mask(device, 0x12004c, 0x2, 0x2);
  61         nvkm_msec(device, 2000,
  62                 if (!(nvkm_rd32(device, 0x12004c) & 0x0000003f))
  63                         break;
  64         );
  65 }
  66
  67 static int
  68 gk20a_ibus_init(struct nvkm_subdev *ibus)
  69 {
  70         gk20a_ibus_init_ibus_ring(ibus);
  71         return 0;
  72 }
  73
  74 static const struct nvkm_subdev_func
  75 gk20a_ibus = {
  76         .init = gk20a_ibus_init,
  77         .intr = gk20a_ibus_intr,
  78 };
  79
  80 int
  81 gk20a_ibus_new(struct nvkm_device *device, int index,
  82                struct nvkm_subdev **pibus)
  83 {
  84         return nvkm_subdev_new_(&gk20a_ibus, device, index, pibus);
  85 }