LXR linux/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
  25static void
  26gk20a_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
  48static void
  49gk20a_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
  67static int
  68gk20a_ibus_init(struct nvkm_subdev *ibus)
  69{
  70        gk20a_ibus_init_ibus_ring(ibus);
  71        return 0;
  72}
  73
  74static const struct nvkm_subdev_func
  75gk20a_ibus = {
  76        .init = gk20a_ibus_init,
  77        .intr = gk20a_ibus_intr,
  78};
  79
  80int
  81gk20a_ibus_new(struct nvkm_device *device, int index,
  82               struct nvkm_subdev **pibus)
  83{
  84        struct nvkm_subdev *ibus;
  85        if (!(ibus = *pibus = kzalloc(sizeof(*ibus), GFP_KERNEL)))
  86                return -ENOMEM;
  87        nvkm_subdev_ctor(&gk20a_ibus, device, index, ibus);
  88        return 0;
  89}
  90