drm/nv50: fix suspend/resume with DP outputs

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_encoder.h b/drivers/gpu/drm/nouveau/nouveau_encoder.h
index 9f28b94..e1df820 100644
--- a/drivers/gpu/drm/nouveau/nouveau_encoder.h
+++ b/drivers/gpu/drm/nouveau/nouveau_encoder.h
@@ -48,6 +48,8 @@
 	union {
 		struct {
 			int mc_unknown;
+			uint32_t unk0;
+			uint32_t unk1;
 			int dpcd_version;
 			int link_nr;
 			int link_bw;
diff --git a/drivers/gpu/drm/nouveau/nouveau_reg.h b/drivers/gpu/drm/nouveau/nouveau_reg.h
index aa9b310..6ca80a3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_reg.h
+++ b/drivers/gpu/drm/nouveau/nouveau_reg.h
@@ -826,6 +826,7 @@
 #define NV50_SOR_DP_CTRL_TRAINING_PATTERN_2                          0x02000000
 #define NV50_SOR_DP_UNK118(i,l)          (0x0061c118 + (i) * 0x800 + (l) * 0x80)
 #define NV50_SOR_DP_UNK120(i,l)          (0x0061c120 + (i) * 0x800 + (l) * 0x80)
+#define NV50_SOR_DP_UNK128(i,l)          (0x0061c128 + (i) * 0x800 + (l) * 0x80)
 #define NV50_SOR_DP_UNK130(i,l)          (0x0061c130 + (i) * 0x800 + (l) * 0x80)
 
 #define NV50_PDISPLAY_USER(i)                        ((i) * 0x1000 + 0x00640000)
diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index 34156b6..580a5d1 100644
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -784,6 +784,37 @@
 }
 
 static void
+nv50_display_unk20_dp_hack(struct drm_device *dev, struct dcb_entry *dcb)
+{
+	int or = ffs(dcb->or) - 1, link = !(dcb->dpconf.sor.link & 1);
+	struct drm_encoder *encoder;
+	uint32_t tmp, unk0 = 0, unk1 = 0;
+
+	if (dcb->type != OUTPUT_DP)
+		return;
+
+	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
+		struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
+
+		if (nv_encoder->dcb == dcb) {
+			unk0 = nv_encoder->dp.unk0;
+			unk1 = nv_encoder->dp.unk1;
+			break;
+		}
+	}
+
+	if (unk0 || unk1) {
+		tmp  = nv_rd32(dev, NV50_SOR_DP_CTRL(or, link));
+		tmp &= 0xfffffe03;
+		nv_wr32(dev, NV50_SOR_DP_CTRL(or, link), tmp | unk0);
+
+		tmp  = nv_rd32(dev, NV50_SOR_DP_UNK128(or, link));
+		tmp &= 0xfef080c0;
+		nv_wr32(dev, NV50_SOR_DP_UNK128(or, link), tmp | unk1);
+	}
+}
+
+static void
 nv50_display_unk20_handler(struct drm_device *dev)
 {
 	struct dcb_entry *dcbent;
@@ -806,6 +837,8 @@
 
 	nouveau_bios_run_display_table(dev, dcbent, script, pclk);
 
+	nv50_display_unk20_dp_hack(dev, dcbent);
+
 	tmp = nv_rd32(dev, NV50_PDISPLAY_CRTC_CLK_CTRL2(head));
 	tmp &= ~0x000000f;
 	nv_wr32(dev, NV50_PDISPLAY_CRTC_CLK_CTRL2(head), tmp);
diff --git a/drivers/gpu/drm/nouveau/nv50_sor.c b/drivers/gpu/drm/nouveau/nv50_sor.c
index 0c68698..b11eaf9 100644
--- a/drivers/gpu/drm/nouveau/nv50_sor.c
+++ b/drivers/gpu/drm/nouveau/nv50_sor.c
@@ -321,18 +321,23 @@
 	encoder->possible_clones = 0;
 
 	if (nv_encoder->dcb->type == OUTPUT_DP) {
-		uint32_t mc, or = nv_encoder->or;
+		int or = nv_encoder->or, link = !(entry->dpconf.sor.link & 1);
+		uint32_t tmp;
 
 		if (dev_priv->chipset < 0x90 ||
 		    dev_priv->chipset == 0x92 || dev_priv->chipset == 0xa0)
-			mc = nv_rd32(dev, NV50_PDISPLAY_SOR_MODE_CTRL_C(or));
+			tmp = nv_rd32(dev, NV50_PDISPLAY_SOR_MODE_CTRL_C(or));
 		else
-			mc = nv_rd32(dev, NV90_PDISPLAY_SOR_MODE_CTRL_C(or));
+			tmp = nv_rd32(dev, NV90_PDISPLAY_SOR_MODE_CTRL_C(or));
 
-		switch ((mc & 0x00000f00) >> 8) {
+		switch ((tmp & 0x00000f00) >> 8) {
 		case 8:
 		case 9:
-			nv_encoder->dp.mc_unknown = (mc & 0x000f0000) >> 16;
+			nv_encoder->dp.mc_unknown = (tmp & 0x000f0000) >> 16;
+			tmp = nv_rd32(dev, NV50_SOR_DP_CTRL(or, link));
+			nv_encoder->dp.unk0 = tmp & 0x000001fc;
+			tmp = nv_rd32(dev, NV50_SOR_DP_UNK128(or, link));
+			nv_encoder->dp.unk1 = tmp & 0x010f7f3f;
 			break;
 		default:
 			break;