1 /* $NetBSD: nouveau_dp.c,v 1.4 2021/12/18 23:45:32 riastradh Exp $ */
2
3 /*
4 * Copyright 2009 Red Hat Inc.
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 COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 *
24 * Authors: Ben Skeggs
25 */
26
27 #include <sys/cdefs.h>
28 __KERNEL_RCSID(0, "$NetBSD: nouveau_dp.c,v 1.4 2021/12/18 23:45:32 riastradh Exp $");
29
30 #include <drm/drm_dp_helper.h>
31
32 #include "nouveau_drv.h"
33 #include "nouveau_connector.h"
34 #include "nouveau_encoder.h"
35 #include "nouveau_crtc.h"
36
37 #include <nvif/class.h>
38 #include <nvif/cl5070.h>
39
40 MODULE_PARM_DESC(mst, "Enable DisplayPort multi-stream (default: enabled)");
41 static int nouveau_mst = 1;
42 module_param_named(mst, nouveau_mst, int, 0400);
43
44 static void
nouveau_dp_probe_oui(struct drm_device * dev,struct nvkm_i2c_aux * aux,u8 * dpcd)45 nouveau_dp_probe_oui(struct drm_device *dev, struct nvkm_i2c_aux *aux, u8 *dpcd)
46 {
47 struct nouveau_drm *drm = nouveau_drm(dev);
48 u8 buf[3];
49
50 if (!(dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
51 return;
52
53 if (!nvkm_rdaux(aux, DP_SINK_OUI, buf, 3))
54 NV_DEBUG(drm, "Sink OUI: %02"PRIx8"%02"PRIx8"%02"PRIx8"\n",
55 buf[0], buf[1], buf[2]);
56
57 if (!nvkm_rdaux(aux, DP_BRANCH_OUI, buf, 3))
58 NV_DEBUG(drm, "Branch OUI: %02"PRIx8"%02"PRIx8"%02"PRIx8"\n",
59 buf[0], buf[1], buf[2]);
60
61 }
62
63 int
nouveau_dp_detect(struct nouveau_encoder * nv_encoder)64 nouveau_dp_detect(struct nouveau_encoder *nv_encoder)
65 {
66 struct drm_device *dev = nv_encoder->base.base.dev;
67 struct nouveau_drm *drm = nouveau_drm(dev);
68 struct nvkm_i2c_aux *aux;
69 u8 dpcd[8];
70 int ret;
71
72 aux = nv_encoder->aux;
73 if (!aux)
74 return -ENODEV;
75
76 ret = nvkm_rdaux(aux, DP_DPCD_REV, dpcd, sizeof(dpcd));
77 if (ret)
78 return ret;
79
80 nv_encoder->dp.link_bw = 27000 * dpcd[1];
81 nv_encoder->dp.link_nr = dpcd[2] & DP_MAX_LANE_COUNT_MASK;
82
83 NV_DEBUG(drm, "display: %dx%d dpcd 0x%02x\n",
84 nv_encoder->dp.link_nr, nv_encoder->dp.link_bw, dpcd[0]);
85 NV_DEBUG(drm, "encoder: %dx%d\n",
86 nv_encoder->dcb->dpconf.link_nr,
87 nv_encoder->dcb->dpconf.link_bw);
88
89 if (nv_encoder->dcb->dpconf.link_nr < nv_encoder->dp.link_nr)
90 nv_encoder->dp.link_nr = nv_encoder->dcb->dpconf.link_nr;
91 if (nv_encoder->dcb->dpconf.link_bw < nv_encoder->dp.link_bw)
92 nv_encoder->dp.link_bw = nv_encoder->dcb->dpconf.link_bw;
93
94 NV_DEBUG(drm, "maximum: %dx%d\n",
95 nv_encoder->dp.link_nr, nv_encoder->dp.link_bw);
96
97 nouveau_dp_probe_oui(dev, aux, dpcd);
98
99 ret = nv50_mstm_detect(nv_encoder->dp.mstm, dpcd, nouveau_mst);
100 if (ret == 1)
101 return NOUVEAU_DP_MST;
102 if (ret == 0)
103 return NOUVEAU_DP_SST;
104 return ret;
105 }
106