1 /*
2  * Copyright 2009 Red Hat 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  * Authors: Ben Skeggs
23  */
24 
25 #include <drm/drmP.h>
26 #include <drm/drm_dp_helper.h>
27 
28 #include "nouveau_drv.h"
29 #include "nouveau_connector.h"
30 #include "nouveau_encoder.h"
31 #include "nouveau_crtc.h"
32 
33 #include <nvif/class.h>
34 #include <nvif/cl5070.h>
35 
36 MODULE_PARM_DESC(mst, "Enable DisplayPort multi-stream (default: enabled)");
37 static int nouveau_mst = 1;
38 module_param_named(mst, nouveau_mst, int, 0400);
39 
40 static void
41 nouveau_dp_probe_oui(struct drm_device *dev, struct nvkm_i2c_aux *aux, u8 *dpcd)
42 {
43 	struct nouveau_drm *drm = nouveau_drm(dev);
44 	u8 buf[3];
45 
46 	if (!(dpcd[DP_DOWN_STREAM_PORT_COUNT] & DP_OUI_SUPPORT))
47 		return;
48 
49 	if (!nvkm_rdaux(aux, DP_SINK_OUI, buf, 3))
50 		NV_DEBUG(drm, "Sink OUI: %02hx%02hx%02hx\n",
51 			     buf[0], buf[1], buf[2]);
52 
53 	if (!nvkm_rdaux(aux, DP_BRANCH_OUI, buf, 3))
54 		NV_DEBUG(drm, "Branch OUI: %02hx%02hx%02hx\n",
55 			     buf[0], buf[1], buf[2]);
56 
57 }
58 
59 int
60 nouveau_dp_detect(struct nouveau_encoder *nv_encoder)
61 {
62 	struct drm_device *dev = nv_encoder->base.base.dev;
63 	struct nouveau_drm *drm = nouveau_drm(dev);
64 	struct nvkm_i2c_aux *aux;
65 	u8 dpcd[8];
66 	int ret;
67 
68 	aux = nv_encoder->aux;
69 	if (!aux)
70 		return -ENODEV;
71 
72 	ret = nvkm_rdaux(aux, DP_DPCD_REV, dpcd, sizeof(dpcd));
73 	if (ret)
74 		return ret;
75 
76 	nv_encoder->dp.link_bw = 27000 * dpcd[1];
77 	nv_encoder->dp.link_nr = dpcd[2] & DP_MAX_LANE_COUNT_MASK;
78 
79 	NV_DEBUG(drm, "display: %dx%d dpcd 0x%02x\n",
80 		     nv_encoder->dp.link_nr, nv_encoder->dp.link_bw, dpcd[0]);
81 	NV_DEBUG(drm, "encoder: %dx%d\n",
82 		     nv_encoder->dcb->dpconf.link_nr,
83 		     nv_encoder->dcb->dpconf.link_bw);
84 
85 	if (nv_encoder->dcb->dpconf.link_nr < nv_encoder->dp.link_nr)
86 		nv_encoder->dp.link_nr = nv_encoder->dcb->dpconf.link_nr;
87 	if (nv_encoder->dcb->dpconf.link_bw < nv_encoder->dp.link_bw)
88 		nv_encoder->dp.link_bw = nv_encoder->dcb->dpconf.link_bw;
89 
90 	NV_DEBUG(drm, "maximum: %dx%d\n",
91 		     nv_encoder->dp.link_nr, nv_encoder->dp.link_bw);
92 
93 	nouveau_dp_probe_oui(dev, aux, dpcd);
94 
95 	ret = nv50_mstm_detect(nv_encoder->dp.mstm, dpcd, nouveau_mst);
96 	if (ret == 1)
97 		return NOUVEAU_DP_MST;
98 	if (ret == 0)
99 		return NOUVEAU_DP_SST;
100 	return ret;
101 }
102