drm/nouveau/disp: introduce acquire/release display path methods

These exist to give NVKM information on the set of display paths that
the DD needs to be active at any given time.

Previously, the supervisor attempted to determine this solely from OR
state, but there's a few configurations where this information on its
own isn't enough to determine the specific display paths in question:

- ANX9805, where the PIOR protocol for both DP and TMDS is TMDS.
- On a device using DCB Switched Outputs.
- On GM20x and newer, with a crossbar between the SOR and macro links.

After this commit, the DD tells NVKM *exactly* which display path it's
attempting a modeset on.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 69 insertions, 6 deletions

diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index e6cc1d843c92..e3132a2ce34d 100644
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -2403,6 +2403,51 @@ out:
 /******************************************************************************
  * Output path helpers
  *****************************************************************************/
+static void
+nv50_outp_release(struct nouveau_encoder *nv_encoder)
+{
+	struct nv50_disp *disp = nv50_disp(nv_encoder->base.base.dev);
+	struct {
+		struct nv50_disp_mthd_v1 base;
+	} args = {
+		.base.version = 1,
+		.base.method = NV50_DISP_MTHD_V1_RELEASE,
+		.base.hasht  = nv_encoder->dcb->hasht,
+		.base.hashm  = nv_encoder->dcb->hashm,
+	};
+
+	nvif_mthd(disp->disp, 0, &args, sizeof(args));
+	nv_encoder->or = -1;
+	nv_encoder->link = 0;
+}
+
+static int
+nv50_outp_acquire(struct nouveau_encoder *nv_encoder)
+{
+	struct nouveau_drm *drm = nouveau_drm(nv_encoder->base.base.dev);
+	struct nv50_disp *disp = nv50_disp(drm->dev);
+	struct {
+		struct nv50_disp_mthd_v1 base;
+		struct nv50_disp_acquire_v0 info;
+	} args = {
+		.base.version = 1,
+		.base.method = NV50_DISP_MTHD_V1_ACQUIRE,
+		.base.hasht  = nv_encoder->dcb->hasht,
+		.base.hashm  = nv_encoder->dcb->hashm,
+	};
+	int ret;
+
+	ret = nvif_mthd(disp->disp, 0, &args, sizeof(args));
+	if (ret) {
+		NV_ERROR(drm, "error acquiring output path: %d\n", ret);
+		return ret;
+	}
+
+	nv_encoder->or = args.info.or;
+	nv_encoder->link = args.info.link;
+	return 0;
+}
+
 static int
 nv50_outp_atomic_check_view(struct drm_encoder *encoder,
 			    struct drm_crtc_state *crtc_state,
@@ -2482,6 +2527,7 @@ nv50_dac_disable(struct drm_encoder *encoder)
 	}
 
 	nv_encoder->crtc = NULL;
+	nv50_outp_release(nv_encoder);
 }
 
 static void
@@ -2493,6 +2539,8 @@ nv50_dac_enable(struct drm_encoder *encoder)
 	struct drm_display_mode *mode = &nv_crtc->base.state->adjusted_mode;
 	u32 *push;
 
+	nv50_outp_acquire(nv_encoder);
+
 	push = evo_wait(mast, 8);
 	if (push) {
 		if (nv50_vers(mast) < GF110_DISP_CORE_CHANNEL_DMA) {
@@ -2592,7 +2640,6 @@ nv50_dac_create(struct drm_connector *connector, struct dcb_output *dcbe)
 	if (!nv_encoder)
 		return -ENOMEM;
 	nv_encoder->dcb = dcbe;
-	nv_encoder->or = ffs(dcbe->or) - 1;
 
 	bus = nvkm_i2c_bus_find(i2c, dcbe->i2c_index);
 	if (bus)
@@ -2759,6 +2806,8 @@ struct nv50_mstm {
 	struct nv50_msto *msto[4];
 
 	bool modified;
+	bool disabled;
+	int links;
 };
 
 struct nv50_mstc {
@@ -2907,7 +2956,10 @@ nv50_msto_enable(struct drm_encoder *encoder)
 	r = drm_dp_mst_allocate_vcpi(&mstm->mgr, mstc->port, mstc->pbn, slots);
 	WARN_ON(!r);
 
-	if (mstm->outp->dcb->sorconf.link & 1)
+	if (!mstm->links++)
+		nv50_outp_acquire(mstm->outp);
+
+	if (mstm->outp->link & 1)
 		proto = 0x8;
 	else
 		proto = 0x9;
@@ -2939,6 +2991,8 @@ nv50_msto_disable(struct drm_encoder *encoder)
 
 	mstm->outp->update(mstm->outp, msto->head->base.index, NULL, 0, 0);
 	mstm->modified = true;
+	if (!--mstm->links)
+		mstm->disabled = true;
 	msto->disabled = true;
 }
 
@@ -3154,6 +3208,12 @@ nv50_mstm_prepare(struct nv50_mstm *mstm)
 				nv50_msto_prepare(msto);
 		}
 	}
+
+	if (mstm->disabled) {
+		if (!mstm->links)
+			nv50_outp_release(mstm->outp);
+		mstm->disabled = false;
+	}
 }
 
 static void
@@ -3452,6 +3512,7 @@ nv50_sor_disable(struct drm_encoder *encoder)
 		nv_encoder->update(nv_encoder, nv_crtc->index, NULL, 0, 0);
 		nv50_audio_disable(encoder, nv_crtc);
 		nv50_hdmi_disable(&nv_encoder->base.base, nv_crtc);
+		nv50_outp_release(nv_encoder);
 	}
 }
 
@@ -3480,10 +3541,11 @@ nv50_sor_enable(struct drm_encoder *encoder)
 
 	nv_connector = nouveau_encoder_connector_get(nv_encoder);
 	nv_encoder->crtc = encoder->crtc;
+	nv50_outp_acquire(nv_encoder);
 
 	switch (nv_encoder->dcb->type) {
 	case DCB_OUTPUT_TMDS:
-		if (nv_encoder->dcb->sorconf.link & 1) {
+		if (nv_encoder->link & 1) {
 			proto = 0x1;
 			/* Only enable dual-link if:
 			 *  - Need to (i.e. rate > 165MHz)
@@ -3541,7 +3603,7 @@ nv50_sor_enable(struct drm_encoder *encoder)
 		else
 			depth = 0x6;
 
-		if (nv_encoder->dcb->sorconf.link & 1)
+		if (nv_encoder->link & 1)
 			proto = 0x8;
 		else
 			proto = 0x9;
@@ -3600,7 +3662,6 @@ nv50_sor_create(struct drm_connector *connector, struct dcb_output *dcbe)
 	if (!nv_encoder)
 		return -ENOMEM;
 	nv_encoder->dcb = dcbe;
-	nv_encoder->or = ffs(dcbe->or) - 1;
 	nv_encoder->update = nv50_sor_update;
 
 	encoder = to_drm_encoder(nv_encoder);
@@ -3673,6 +3734,7 @@ nv50_pior_disable(struct drm_encoder *encoder)
 	}
 
 	nv_encoder->crtc = NULL;
+	nv50_outp_release(nv_encoder);
 }
 
 static void
@@ -3687,6 +3749,8 @@ nv50_pior_enable(struct drm_encoder *encoder)
 	u8 proto, depth;
 	u32 *push;
 
+	nv50_outp_acquire(nv_encoder);
+
 	nv_connector = nouveau_encoder_connector_get(nv_encoder);
 	switch (nv_connector->base.display_info.bpc) {
 	case 10: depth = 0x6; break;
@@ -3774,7 +3838,6 @@ nv50_pior_create(struct drm_connector *connector, struct dcb_output *dcbe)
 	if (!nv_encoder)
 		return -ENOMEM;
 	nv_encoder->dcb = dcbe;
-	nv_encoder->or = ffs(dcbe->or) - 1;
 	nv_encoder->i2c = ddc;
 	nv_encoder->aux = aux;