drm/nouveau/kms: Search for encoders' connectors properly

While the way we find the associated connector for an encoder is just
fine for legacy modesetting, it's not correct for nv50+ since that uses
atomic modesetting. For reference, see the drm_encoder kdocs.

Fix this by removing nouveau_encoder_connector_get(), and replacing it
with nv04_encoder_get_connector(), nv50_outp_get_old_connector(), and
nv50_outp_get_new_connector().

v2:
* Don't line-wrap for_each_(old|new)_connector_in_state in
  nv50_outp_get_(old|new)_connector() - sravn
v3:
* Fix potential uninitialized usage of nv_connector (needs to be
  initialized to NULL at the start). Thanks kernel test robot!
v4:
* Actually fix uninitialized nv_connector usage in
  nv50_audio_component_get_eld(). The previous fix wouldn't have worked
  since we would have started out with nv_connector == NULL, but
  wouldn't clear it after a single drm_for_each_encoder() iteration.
  Thanks again Kernel bot!

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200826182456.322681-7-lyude@redhat.com

drivers/gpu/drm/nouveau/dispnv04/dac.c

@@ -419,7 +419,7 @@ static void nv04_dac_commit(struct drm_encoder *encoder)
 	helper->dpms(encoder, DRM_MODE_DPMS_ON);
 
 	NV_DEBUG(drm, "Output %s is running on CRTC %d using output %c\n",
-		 nouveau_encoder_connector_get(nv_encoder)->base.name,
+		 nv04_encoder_get_connector(nv_encoder)->base.name,
 		 nv_crtc->index, '@' + ffs(nv_encoder->dcb->or));
 }
 

drivers/gpu/drm/nouveau/dispnv04/dfp.c

@@ -184,7 +184,8 @@ static bool nv04_dfp_mode_fixup(struct drm_encoder *encoder,
 				struct drm_display_mode *adjusted_mode)
 {
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
-	struct nouveau_connector *nv_connector = nouveau_encoder_connector_get(nv_encoder);
+	struct nouveau_connector *nv_connector =
+		nv04_encoder_get_connector(nv_encoder);
 
 	if (!nv_connector->native_mode ||
 	    nv_connector->scaling_mode == DRM_MODE_SCALE_NONE ||
@@ -478,7 +479,7 @@ static void nv04_dfp_commit(struct drm_encoder *encoder)
 	helper->dpms(encoder, DRM_MODE_DPMS_ON);
 
 	NV_DEBUG(drm, "Output %s is running on CRTC %d using output %c\n",
-		 nouveau_encoder_connector_get(nv_encoder)->base.name,
+		 nv04_encoder_get_connector(nv_encoder)->base.name,
 		 nv_crtc->index, '@' + ffs(nv_encoder->dcb->or));
 }
 
@@ -591,7 +592,7 @@ static void nv04_dfp_restore(struct drm_encoder *encoder)
 
 	if (nv_encoder->dcb->type == DCB_OUTPUT_LVDS) {
 		struct nouveau_connector *connector =
-			nouveau_encoder_connector_get(nv_encoder);
+			nv04_encoder_get_connector(nv_encoder);
 
 		if (connector && connector->native_mode)
 			call_lvds_script(dev, nv_encoder->dcb, head,

drivers/gpu/drm/nouveau/dispnv04/disp.c

@@ -35,6 +35,24 @@
 
 #include <nvif/if0004.h>
 
+struct nouveau_connector *
+nv04_encoder_get_connector(struct nouveau_encoder *encoder)
+{
+	struct drm_device *dev = to_drm_encoder(encoder)->dev;
+	struct drm_connector *connector;
+	struct drm_connector_list_iter conn_iter;
+	struct nouveau_connector *nv_connector = NULL;
+
+	drm_connector_list_iter_begin(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
+		if (connector->encoder == to_drm_encoder(encoder))
+			nv_connector = nouveau_connector(connector);
+	}
+	drm_connector_list_iter_end(&conn_iter);
+
+	return nv_connector;
+}
+
 static void
 nv04_display_fini(struct drm_device *dev, bool suspend)
 {

drivers/gpu/drm/nouveau/dispnv04/disp.h

@@ -6,6 +6,8 @@
 
 #include "nouveau_display.h"
 
+struct nouveau_encoder;
+
 enum nv04_fp_display_regs {
 	FP_DISPLAY_END,
 	FP_TOTAL,
@@ -93,6 +95,8 @@ nv04_display(struct drm_device *dev)
 
 /* nv04_display.c */
 int nv04_display_create(struct drm_device *);
+struct nouveau_connector *
+nv04_encoder_get_connector(struct nouveau_encoder *nv_encoder);
 
 /* nv04_crtc.c */
 int nv04_crtc_create(struct drm_device *, int index);

drivers/gpu/drm/nouveau/dispnv04/tvnv04.c

@@ -172,7 +172,7 @@ static void nv04_tv_commit(struct drm_encoder *encoder)
 	helper->dpms(encoder, DRM_MODE_DPMS_ON);
 
 	NV_DEBUG(drm, "Output %s is running on CRTC %d using output %c\n",
-		 nouveau_encoder_connector_get(nv_encoder)->base.name,
+		 nv04_encoder_get_connector(nv_encoder)->base.name,
 		 nv_crtc->index, '@' + ffs(nv_encoder->dcb->or));
 }
 

drivers/gpu/drm/nouveau/dispnv04/tvnv17.c

@@ -599,7 +599,7 @@ static void nv17_tv_commit(struct drm_encoder *encoder)
 	helper->dpms(encoder, DRM_MODE_DPMS_ON);
 
 	NV_INFO(drm, "Output %s is running on CRTC %d using output %c\n",
-		nouveau_encoder_connector_get(nv_encoder)->base.name,
+		nv04_encoder_get_connector(nv_encoder)->base.name,
 		nv_crtc->index, '@' + ffs(nv_encoder->dcb->or));
 }
 

drivers/gpu/drm/nouveau/dispnv50/disp.c

@@ -411,6 +411,40 @@ nv50_outp_atomic_check(struct drm_encoder *encoder,
 	return 0;
 }
 
+struct nouveau_connector *
+nv50_outp_get_new_connector(struct nouveau_encoder *outp,
+			    struct drm_atomic_state *state)
+{
+	struct drm_connector *connector;
+	struct drm_connector_state *connector_state;
+	struct drm_encoder *encoder = to_drm_encoder(outp);
+	int i;
+
+	for_each_new_connector_in_state(state, connector, connector_state, i) {
+		if (connector_state->best_encoder == encoder)
+			return nouveau_connector(connector);
+	}
+
+	return NULL;
+}
+
+struct nouveau_connector *
+nv50_outp_get_old_connector(struct nouveau_encoder *outp,
+			    struct drm_atomic_state *state)
+{
+	struct drm_connector *connector;
+	struct drm_connector_state *connector_state;
+	struct drm_encoder *encoder = to_drm_encoder(outp);
+	int i;
+
+	for_each_old_connector_in_state(state, connector, connector_state, i) {
+		if (connector_state->best_encoder == encoder)
+			return nouveau_connector(connector);
+	}
+
+	return NULL;
+}
+
 /******************************************************************************
  * DAC
  *****************************************************************************/
@@ -552,16 +586,31 @@ nv50_audio_component_get_eld(struct device *kdev, int port, int dev_id,
 	struct nouveau_drm *drm = nouveau_drm(drm_dev);
 	struct drm_encoder *encoder;
 	struct nouveau_encoder *nv_encoder;
-	struct nouveau_connector *nv_connector;
+	struct drm_connector *connector;
 	struct nouveau_crtc *nv_crtc;
+	struct drm_connector_list_iter conn_iter;
 	int ret = 0;
 
 	*enabled = false;
+
 	drm_for_each_encoder(encoder, drm->dev) {
+		struct nouveau_connector *nv_connector = NULL;
+
 		nv_encoder = nouveau_encoder(encoder);
-		nv_connector = nouveau_encoder_connector_get(nv_encoder);
+
+		drm_connector_list_iter_begin(drm_dev, &conn_iter);
+		drm_for_each_connector_iter(connector, &conn_iter) {
+			if (connector->state->best_encoder == encoder) {
+				nv_connector = nouveau_connector(connector);
+				break;
+			}
+		}
+		drm_connector_list_iter_end(&conn_iter);
+		if (!nv_connector)
+			continue;
+
 		nv_crtc = nouveau_crtc(encoder->crtc);
-		if (!nv_connector || !nv_crtc || nv_encoder->or != port ||
+		if (!nv_crtc || nv_encoder->or != port ||
 		    nv_crtc->index != dev_id)
 			continue;
 		*enabled = nv_encoder->audio;
@@ -572,6 +621,7 @@ nv50_audio_component_get_eld(struct device *kdev, int port, int dev_id,
 		}
 		break;
 	}
+
 	return ret;
 }
 
@@ -665,7 +715,8 @@ nv50_audio_disable(struct drm_encoder *encoder, struct nouveau_crtc *nv_crtc)
 }
 
 static void
-nv50_audio_enable(struct drm_encoder *encoder, struct drm_display_mode *mode)
+nv50_audio_enable(struct drm_encoder *encoder, struct drm_atomic_state *state,
+		  struct drm_display_mode *mode)
 {
 	struct nouveau_drm *drm = nouveau_drm(encoder->dev);
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
@@ -686,7 +737,7 @@ nv50_audio_enable(struct drm_encoder *encoder, struct drm_display_mode *mode)
 				     (0x0100 << nv_crtc->index),
 	};
 
-	nv_connector = nouveau_encoder_connector_get(nv_encoder);
+	nv_connector = nv50_outp_get_new_connector(nv_encoder, state);
 	if (!drm_detect_monitor_audio(nv_connector->edid))
 		return;
 
@@ -723,7 +774,8 @@ nv50_hdmi_disable(struct drm_encoder *encoder, struct nouveau_crtc *nv_crtc)
 }
 
 static void
-nv50_hdmi_enable(struct drm_encoder *encoder, struct drm_display_mode *mode)
+nv50_hdmi_enable(struct drm_encoder *encoder, struct drm_atomic_state *state,
+		 struct drm_display_mode *mode)
 {
 	struct nouveau_drm *drm = nouveau_drm(encoder->dev);
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
@@ -752,7 +804,7 @@ nv50_hdmi_enable(struct drm_encoder *encoder, struct drm_display_mode *mode)
 	int ret;
 	int size;
 
-	nv_connector = nouveau_encoder_connector_get(nv_encoder);
+	nv_connector = nv50_outp_get_new_connector(nv_encoder, state);
 	if (!drm_detect_hdmi_monitor(nv_connector->edid))
 		return;
 
@@ -798,7 +850,7 @@ nv50_hdmi_enable(struct drm_encoder *encoder, struct drm_display_mode *mode)
 		+ args.pwr.vendor_infoframe_length;
 	nvif_mthd(&disp->disp->object, 0, &args, size);
 
-	nv50_audio_enable(encoder, mode);
+	nv50_audio_enable(encoder, state, mode);
 
 	/* If SCDC is supported by the downstream monitor, update
 	 * divider / scrambling settings to what we programmed above.
@@ -1573,7 +1625,8 @@ nv50_sor_update(struct nouveau_encoder *nv_encoder, u8 head,
 }
 
 static void
-nv50_sor_disable(struct drm_encoder *encoder)
+nv50_sor_disable(struct drm_encoder *encoder,
+		 struct drm_atomic_state *state)
 {
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 	struct nouveau_crtc *nv_crtc = nouveau_crtc(nv_encoder->crtc);
@@ -1601,7 +1654,8 @@ nv50_sor_disable(struct drm_encoder *encoder)
 }
 
 static void
-nv50_sor_enable(struct drm_encoder *encoder)
+nv50_sor_enable(struct drm_encoder *encoder,
+		struct drm_atomic_state *state)
 {
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 	struct nouveau_crtc *nv_crtc = nouveau_crtc(encoder->crtc);
@@ -1625,7 +1679,7 @@ nv50_sor_enable(struct drm_encoder *encoder)
 	u8 proto = NV507D_SOR_SET_CONTROL_PROTOCOL_CUSTOM;
 	u8 depth = NV837D_SOR_SET_CONTROL_PIXEL_DEPTH_DEFAULT;
 
-	nv_connector = nouveau_encoder_connector_get(nv_encoder);
+	nv_connector = nv50_outp_get_new_connector(nv_encoder, state);
 	nv_encoder->crtc = encoder->crtc;
 
 	if ((disp->disp->object.oclass == GT214_DISP ||
@@ -1652,7 +1706,7 @@ nv50_sor_enable(struct drm_encoder *encoder)
 			proto = NV507D_SOR_SET_CONTROL_PROTOCOL_SINGLE_TMDS_B;
 		}
 
-		nv50_hdmi_enable(&nv_encoder->base.base, mode);
+		nv50_hdmi_enable(&nv_encoder->base.base, state, mode);
 		break;
 	case DCB_OUTPUT_LVDS:
 		proto = NV507D_SOR_SET_CONTROL_PROTOCOL_LVDS_CUSTOM;
@@ -1693,7 +1747,7 @@ nv50_sor_enable(struct drm_encoder *encoder)
 		else
 			proto = NV887D_SOR_SET_CONTROL_PROTOCOL_DP_B;
 
-		nv50_audio_enable(encoder, mode);
+		nv50_audio_enable(encoder, state, mode);
 		break;
 	default:
 		BUG();
@@ -1706,8 +1760,8 @@ nv50_sor_enable(struct drm_encoder *encoder)
 static const struct drm_encoder_helper_funcs
 nv50_sor_help = {
 	.atomic_check = nv50_outp_atomic_check,
-	.enable = nv50_sor_enable,
-	.disable = nv50_sor_disable,
+	.atomic_enable = nv50_sor_enable,
+	.atomic_disable = nv50_sor_disable,
 };
 
 static void
@@ -2066,7 +2120,7 @@ nv50_disp_atomic_commit_tail(struct drm_atomic_state *state)
 			  outp->clr.mask, outp->set.mask);
 
 		if (outp->clr.mask) {
-			help->disable(encoder);
+			help->atomic_disable(encoder, state);
 			interlock[NV50_DISP_INTERLOCK_CORE] |= 1;
 			if (outp->flush_disable) {
 				nv50_disp_atomic_commit_wndw(state, interlock);
@@ -2105,7 +2159,7 @@ nv50_disp_atomic_commit_tail(struct drm_atomic_state *state)
 			  outp->set.mask, outp->clr.mask);
 
 		if (outp->set.mask) {
-			help->enable(encoder);
+			help->atomic_enable(encoder, state);
 			interlock[NV50_DISP_INTERLOCK_CORE] = 1;
 		}
 

drivers/gpu/drm/nouveau/nouveau_connector.c

@@ -391,20 +391,6 @@ find_encoder(struct drm_connector *connector, int type)
 	return NULL;
 }
 
-struct nouveau_connector *
-nouveau_encoder_connector_get(struct nouveau_encoder *encoder)
-{
-	struct drm_device *dev = to_drm_encoder(encoder)->dev;
-	struct drm_connector *drm_connector;
-
-	list_for_each_entry(drm_connector, &dev->mode_config.connector_list, head) {
-		if (drm_connector->encoder == to_drm_encoder(encoder))
-			return nouveau_connector(drm_connector);
-	}
-
-	return NULL;
-}
-
 static void
 nouveau_connector_destroy(struct drm_connector *connector)
 {

drivers/gpu/drm/nouveau/nouveau_encoder.h

@@ -113,7 +113,11 @@ enum drm_mode_status nv50_dp_mode_valid(struct drm_connector *,
 					unsigned *clock);
 
 struct nouveau_connector *
-nouveau_encoder_connector_get(struct nouveau_encoder *encoder);
+nv50_outp_get_new_connector(struct nouveau_encoder *outp,
+			    struct drm_atomic_state *state);
+struct nouveau_connector *
+nv50_outp_get_old_connector(struct nouveau_encoder *outp,
+			    struct drm_atomic_state *state);
 
 int nv50_mstm_detect(struct nv50_mstm *, u8 dpcd[8], int allow);
 void nv50_mstm_remove(struct nv50_mstm *);