drm/nouveau/disp: move DP link config into acquire

Aside from fixing MST->SST switching (KMS never turned off MST link config),
this should preserve existing behaviour for the moment, but provide a path
for the KMS driver to have more explicit control of the DP link, which has
been requested by Lyude.

More research into modeset/supervisor interactions is needed before we can
have fully explicit control from the KMS driver.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

4 files changed, 46 insertions, 19 deletions

diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c
index c1b3206f27e6..f1887b58f472 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c
@@ -287,7 +287,7 @@ nvkm_dp_train_links(struct nvkm_outp *outp, int rate)
 	u8 sink[2], data;
 	int ret;
 
-	OUTP_DBG(outp, "training %d x %d MB/s", ior->dp.nr, ior->dp.bw * 27);
+	OUTP_DBG(outp, "training %dx%02x", ior->dp.nr, ior->dp.bw);
 
 	/* Intersect misc. capabilities of the OR and sink. */
 	if (disp->engine.subdev.device->chipset < 0x110)
@@ -455,6 +455,21 @@ nvkm_dp_train(struct nvkm_outp *outp, u32 dataKBps)
 	/* Link training. */
 	OUTP_DBG(outp, "training");
 	nvkm_dp_train_init(outp);
+
+	/* Validate and train at configuration requested (if any) on ACQUIRE. */
+	if (outp->dp.lt.nr) {
+		for (nr = outp->dp.links; ret < 0 && nr; nr >>= 1) {
+			for (rate = 0; nr == outp->dp.lt.nr && rate < outp->dp.rates; rate++) {
+				if (outp->dp.rate[rate].rate / 27000 == outp->dp.lt.bw) {
+					ior->dp.bw = outp->dp.rate[rate].rate / 27000;
+					ior->dp.nr = nr;
+					ret = nvkm_dp_train_links(outp, rate);
+				}
+			}
+		}
+	}
+
+	/* Otherwise, loop through all valid link configurations that support the data rate. */
 	for (nr = outp->dp.links; ret < 0 && nr; nr >>= 1) {
 		for (rate = 0; ret < 0 && rate < outp->dp.rates; rate++) {
 			if (outp->dp.rate[rate].rate * nr >= dataKBps || WARN_ON(!ior->dp.nr)) {
@@ -465,6 +480,8 @@ nvkm_dp_train(struct nvkm_outp *outp, u32 dataKBps)
 			}
 		}
 	}
+
+	/* Finish up. */
 	nvkm_dp_train_fini(outp);
 	if (ret < 0)
 		OUTP_ERR(outp, "training failed");
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h b/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
index eb9cd1146825..d7c989e1cd01 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
@@ -54,6 +54,8 @@ struct nvkm_outp {
 			struct mutex mutex;
 			struct {
 				atomic_t done;
+				u8 nr;
+				u8 bw;
 				bool mst;
 			} lt;
 		} dp;
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/rootnv50.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/rootnv50.c
index a5bb15b62a0c..2f42940367a0 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/rootnv50.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/rootnv50.c
@@ -91,21 +91,6 @@ nv50_disp_root_mthd_(struct nvkm_object *object, u32 mthd, void *data, u32 size)
 	}
 
 	switch (mthd * !!outp) {
-	case NV50_DISP_MTHD_V1_SOR_DP_MST_LINK: {
-		union {
-			struct nv50_disp_sor_dp_mst_link_v0 v0;
-		} *args = data;
-		int ret = -ENOSYS;
-		nvif_ioctl(object, "disp sor dp mst link size %d\n", size);
-		if (!(ret = nvif_unpack(ret, &data, &size, args->v0, 0, 0, false))) {
-			nvif_ioctl(object, "disp sor dp mst link vers %d state %d\n",
-				   args->v0.version, args->v0.state);
-			outp->dp.lt.mst = !!args->v0.state;
-			return 0;
-		} else
-			return ret;
-	}
-		break;
 	case NV50_DISP_MTHD_V1_SOR_DP_MST_VCPI: {
 		union {
 			struct nv50_disp_sor_dp_mst_vcpi_v0 v0;
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
index 052b2d14f47a..61d41b326f43 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
@@ -101,6 +101,23 @@ nvkm_uoutp_mthd_release(struct nvkm_outp *outp, void *argv, u32 argc)
 }
 
 static int
+nvkm_uoutp_mthd_acquire_dp(struct nvkm_outp *outp, u8 dpcd[16],
+			   u8 link_nr, u8 link_bw, bool hda, bool mst)
+{
+	int ret;
+
+	ret = nvkm_outp_acquire(outp, NVKM_OUTP_USER, hda);
+	if (ret)
+		return ret;
+
+	memcpy(outp->dp.dpcd, dpcd, sizeof(outp->dp.dpcd));
+	outp->dp.lt.nr = link_nr;
+	outp->dp.lt.bw = link_bw;
+	outp->dp.lt.mst = mst;
+	return 0;
+}
+
+static int
 nvkm_uoutp_mthd_acquire_tmds(struct nvkm_outp *outp, u8 head, u8 hdmi, u8 hdmi_max_ac_packet,
 			     u8 hdmi_rekey, u8 hdmi_scdc, u8 hdmi_hda)
 {
@@ -152,6 +169,8 @@ nvkm_uoutp_mthd_acquire(struct nvkm_outp *outp, void *argv, u32 argc)
 
 	if (argc != sizeof(args->v0) || args->v0.version != 0)
 		return -ENOSYS;
+	if (outp->ior)
+		return -EBUSY;
 
 	switch (args->v0.proto) {
 	case NVIF_OUTP_ACQUIRE_V0_RGB_CRT:
@@ -165,12 +184,16 @@ nvkm_uoutp_mthd_acquire(struct nvkm_outp *outp, void *argv, u32 argc)
 							 args->v0.tmds.hdmi_scdc,
 							 args->v0.tmds.hdmi_hda);
 		break;
-	case NVIF_OUTP_ACQUIRE_V0_DP:
-		ret = nvkm_outp_acquire(outp, NVKM_OUTP_USER, args->v0.dp.hda);
-		break;
 	case NVIF_OUTP_ACQUIRE_V0_LVDS:
 		ret = nvkm_uoutp_mthd_acquire_lvds(outp, args->v0.lvds.dual, args->v0.lvds.bpc8);
 		break;
+	case NVIF_OUTP_ACQUIRE_V0_DP:
+		ret = nvkm_uoutp_mthd_acquire_dp(outp, args->v0.dp.dpcd,
+						       args->v0.dp.link_nr,
+						       args->v0.dp.link_bw,
+						       args->v0.dp.hda != 0,
+						       args->v0.dp.mst != 0);
+		break;
 	default:
 		ret = -EINVAL;
 		break;