1 /* $NetBSD: nouveau_nvkm_subdev_ibus_gk20a.c,v 1.3 2021/12/18 23:45:40 riastradh Exp $ */
2
3 /*
4 * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
23 */
24 #include <sys/cdefs.h>
25 __KERNEL_RCSID(0, "$NetBSD: nouveau_nvkm_subdev_ibus_gk20a.c,v 1.3 2021/12/18 23:45:40 riastradh Exp $");
26
27 #include <subdev/ibus.h>
28 #include <subdev/timer.h>
29
30 static void
gk20a_ibus_init_ibus_ring(struct nvkm_subdev * ibus)31 gk20a_ibus_init_ibus_ring(struct nvkm_subdev *ibus)
32 {
33 struct nvkm_device *device = ibus->device;
34 nvkm_mask(device, 0x137250, 0x3f, 0);
35
36 nvkm_mask(device, 0x000200, 0x20, 0);
37 udelay(20);
38 nvkm_mask(device, 0x000200, 0x20, 0x20);
39
40 nvkm_wr32(device, 0x12004c, 0x4);
41 nvkm_wr32(device, 0x122204, 0x2);
42 nvkm_rd32(device, 0x122204);
43
44 /*
45 * Bug: increase clock timeout to avoid operation failure at high
46 * gpcclk rate.
47 */
48 nvkm_wr32(device, 0x122354, 0x800);
49 nvkm_wr32(device, 0x128328, 0x800);
50 nvkm_wr32(device, 0x124320, 0x800);
51 }
52
53 static void
gk20a_ibus_intr(struct nvkm_subdev * ibus)54 gk20a_ibus_intr(struct nvkm_subdev *ibus)
55 {
56 struct nvkm_device *device = ibus->device;
57 u32 status0 = nvkm_rd32(device, 0x120058);
58
59 if (status0 & 0x7) {
60 nvkm_debug(ibus, "resetting ibus ring\n");
61 gk20a_ibus_init_ibus_ring(ibus);
62 }
63
64 /* Acknowledge interrupt */
65 nvkm_mask(device, 0x12004c, 0x2, 0x2);
66 nvkm_msec(device, 2000,
67 if (!(nvkm_rd32(device, 0x12004c) & 0x0000003f))
68 break;
69 );
70 }
71
72 static int
gk20a_ibus_init(struct nvkm_subdev * ibus)73 gk20a_ibus_init(struct nvkm_subdev *ibus)
74 {
75 gk20a_ibus_init_ibus_ring(ibus);
76 return 0;
77 }
78
79 static const struct nvkm_subdev_func
80 gk20a_ibus = {
81 .init = gk20a_ibus_init,
82 .intr = gk20a_ibus_intr,
83 };
84
85 int
gk20a_ibus_new(struct nvkm_device * device,int index,struct nvkm_subdev ** pibus)86 gk20a_ibus_new(struct nvkm_device *device, int index,
87 struct nvkm_subdev **pibus)
88 {
89 struct nvkm_subdev *ibus;
90 if (!(ibus = *pibus = kzalloc(sizeof(*ibus), GFP_KERNEL)))
91 return -ENOMEM;
92 nvkm_subdev_ctor(&gk20a_ibus, device, index, ibus);
93 return 0;
94 }
95