drm/nouveau/disp/dp: explicitly control scrambling when setting pattern

TPS1/2/3 require scrambling to be disabled.  The IED scripts on earlier
boards used to handle this, but appear not to anymore.

TPS4 support will also require scrambling to remain enabled.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Link: https://gitlab.freedesktop.org/drm/nouveau/-/merge_requests/17

drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c

@@ -154,6 +154,11 @@ nvkm_dp_train_pattern(struct lt_state *lt, u8 pattern)
 	nvkm_rdaux(dp->aux, DPCD_LC02, &sink_tp, 1);
 	sink_tp &= ~DPCD_LC02_TRAINING_PATTERN_SET;
 	sink_tp |= pattern;
+
+	if (pattern != 0)
+		sink_tp |=  DPCD_LC02_SCRAMBLING_DISABLE;
+	else
+		sink_tp &= ~DPCD_LC02_SCRAMBLING_DISABLE;
 	nvkm_wraux(dp->aux, DPCD_LC02, &sink_tp, 1);
 }
 

drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.h

@@ -49,6 +49,7 @@ void nvkm_dp_disable(struct nvkm_outp *, struct nvkm_ior *);
 #define DPCD_LC01_LANE_COUNT_SET                                           0x1f
 #define DPCD_LC02                                                       0x00102
 #define DPCD_LC02_TRAINING_PATTERN_SET                                     0x03
+#define DPCD_LC02_SCRAMBLING_DISABLE                                       0x20
 #define DPCD_LC03(l)                                            ((l) +  0x00103)
 #define DPCD_LC03_MAX_PRE_EMPHASIS_REACHED                                 0x20
 #define DPCD_LC03_PRE_EMPHASIS_SET                                         0x18

drivers/gpu/drm/nouveau/nvkm/engine/disp/sorg94.c

@@ -77,7 +77,18 @@ g94_sor_dp_pattern(struct nvkm_ior *sor, int pattern)
 {
 	struct nvkm_device *device = sor->disp->engine.subdev.device;
 	const u32 loff = nv50_sor_link(sor);
-	nvkm_mask(device, 0x61c10c + loff, 0x0f000000, pattern << 24);
+	u32 data;
+
+	switch (pattern) {
+	case 0: data = 0x00001000; break;
+	case 1: data = 0x01000000; break;
+	case 2: data = 0x02000000; break;
+	default:
+		WARN_ON(1);
+		return;
+	}
+
+	nvkm_mask(device, 0x61c10c + loff, 0x0f001000, data);
 }
 
 void

drivers/gpu/drm/nouveau/nvkm/engine/disp/sorgf119.c

@@ -92,7 +92,19 @@ gf119_sor_dp_pattern(struct nvkm_ior *sor, int pattern)
 {
 	struct nvkm_device *device = sor->disp->engine.subdev.device;
 	const u32 soff = nv50_ior_base(sor);
-	nvkm_mask(device, 0x61c110 + soff, 0x0f0f0f0f, 0x01010101 * pattern);
+	u32 data;
+
+	switch (pattern) {
+	case 0: data = 0x10101010; break;
+	case 1: data = 0x01010101; break;
+	case 2: data = 0x02020202; break;
+	case 3: data = 0x03030303; break;
+	default:
+		WARN_ON(1);
+		return;
+	}
+
+	nvkm_mask(device, 0x61c110 + soff, 0x1f1f1f1f, data);
 }
 
 int

drivers/gpu/drm/nouveau/nvkm/engine/disp/sorgm107.c

@@ -28,11 +28,22 @@ gm107_sor_dp_pattern(struct nvkm_ior *sor, int pattern)
 {
 	struct nvkm_device *device = sor->disp->engine.subdev.device;
 	const u32 soff = nv50_ior_base(sor);
-	const u32 data = 0x01010101 * pattern;
+	u32 mask = 0x1f1f1f1f, data;
+
+	switch (pattern) {
+	case 0: data = 0x10101010; break;
+	case 1: data = 0x01010101; break;
+	case 2: data = 0x02020202; break;
+	case 3: data = 0x03030303; break;
+	default:
+		WARN_ON(1);
+		return;
+	}
+
 	if (sor->asy.link & 1)
-		nvkm_mask(device, 0x61c110 + soff, 0x0f0f0f0f, data);
+		nvkm_mask(device, 0x61c110 + soff, mask, data);
 	else
-		nvkm_mask(device, 0x61c12c + soff, 0x0f0f0f0f, data);
+		nvkm_mask(device, 0x61c12c + soff, mask, data);
 }
 
 static const struct nvkm_ior_func