[PATCH 2/2] drm/vc4: Add support for interlaced modes on HDMI.

[Eric Anholt <eric@anholt.net>]

We just needed to initialize a few more fields.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/vc4/vc4_crtc.c | 17 ++++++++++++++---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 12 ++++++++----
 drivers/gpu/drm/vc4/vc4_regs.h |  3 +++
 3 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 8fc2b731b59a..d575f8aa3273 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -428,13 +428,24 @@ static void vc4_crtc_mode_set_nofb(struct drm_crtc *crtc)
 			   VC4_SET_FIELD(mode->vsync_start - mode->vdisplay,
 					 PV_VERTB_VFP) |
 			   VC4_SET_FIELD(vactive, PV_VERTB_VACTIVE));
+
+		/* We set up first field even mode for HDMI.  VEC's
+		 * NTSC mode would want first field odd instead, once
+		 * we support it (to do so, set ODD_FIRST and put the
+		 * delay in VSYNCD_EVEN instead).
+		 */
+		CRTC_WRITE(PV_V_CONTROL,
+			   PV_VCONTROL_CONTINUOUS |
+			   PV_VCONTROL_INTERLACE |
+			   VC4_SET_FIELD(mode->htotal / 2,
+					 PV_VCONTROL_ODD_DELAY));
+		CRTC_WRITE(PV_VSYNCD_EVEN, 0);
+	} else {
+		CRTC_WRITE(PV_V_CONTROL, PV_VCONTROL_CONTINUOUS);
 	}
 
 	CRTC_WRITE(PV_HACT_ACT, mode->hdisplay);
 
-	CRTC_WRITE(PV_V_CONTROL,
-		   PV_VCONTROL_CONTINUOUS |
-		   (interlace ? PV_VCONTROL_INTERLACE : 0));
 
 	CRTC_WRITE(PV_CONTROL,
 		   VC4_SET_FIELD(format, PV_CONTROL_FORMAT) |
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 5770d6704f4b..6095e48fcf46 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -246,7 +246,7 @@ static struct drm_connector *vc4_hdmi_connector_init(struct drm_device *dev,
 	connector->polled = (DRM_CONNECTOR_POLL_CONNECT |
 			     DRM_CONNECTOR_POLL_DISCONNECT);
 
-	connector->interlace_allowed = 0;
+	connector->interlace_allowed = true;
 	connector->doublescan_allowed = 0;
 
 	drm_mode_connector_attach_encoder(connector, encoder);
@@ -278,8 +278,8 @@ static void vc4_hdmi_encoder_mode_set(struct drm_encoder *encoder,
 	bool debug_dump_regs = false;
 	bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC;
 	bool vsync_pos = mode->flags & DRM_MODE_FLAG_PVSYNC;
-	u32 vactive = (mode->vdisplay >>
-		       ((mode->flags & DRM_MODE_FLAG_INTERLACE) ? 1 : 0));
+	bool interlaced = mode->flags & DRM_MODE_FLAG_INTERLACE;
+	u32 vactive = mode->vdisplay >> interlaced;
 	u32 verta = (VC4_SET_FIELD(mode->vsync_end - mode->vsync_start,
 				   VC4_HDMI_VERTA_VSP) |
 		     VC4_SET_FIELD(mode->vsync_start - mode->vdisplay,
@@ -288,6 +288,10 @@ static void vc4_hdmi_encoder_mode_set(struct drm_encoder *encoder,
 	u32 vertb = (VC4_SET_FIELD(0, VC4_HDMI_VERTB_VSPO) |
 		     VC4_SET_FIELD(mode->vtotal - mode->vsync_end,
 				   VC4_HDMI_VERTB_VBP));
+	u32 vertb_even = (VC4_SET_FIELD(0, VC4_HDMI_VERTB_VSPO) |
+			  VC4_SET_FIELD(mode->vtotal - mode->vsync_end -
+					interlaced,
+					VC4_HDMI_VERTB_VBP));
 
 	if (debug_dump_regs) {
 		DRM_INFO("HDMI regs before:\n");
@@ -319,7 +323,7 @@ static void vc4_hdmi_encoder_mode_set(struct drm_encoder *encoder,
 	HDMI_WRITE(VC4_HDMI_VERTA0, verta);
 	HDMI_WRITE(VC4_HDMI_VERTA1, verta);
 
-	HDMI_WRITE(VC4_HDMI_VERTB0, vertb);
+	HDMI_WRITE(VC4_HDMI_VERTB0, vertb_even);
 	HDMI_WRITE(VC4_HDMI_VERTB1, vertb);
 
 	HD_WRITE(VC4_HD_VID_CTL,
diff --git a/drivers/gpu/drm/vc4/vc4_regs.h b/drivers/gpu/drm/vc4/vc4_regs.h
index 160942a9180e..fec7b5ef058b 100644
--- a/drivers/gpu/drm/vc4/vc4_regs.h
+++ b/drivers/gpu/drm/vc4/vc4_regs.h
@@ -183,6 +183,9 @@
 # define PV_CONTROL_EN				BIT(0)
 
 #define PV_V_CONTROL				0x04
+# define PV_VCONTROL_ODD_DELAY_MASK		VC4_MASK(22, 6)
+# define PV_VCONTROL_ODD_DELAY_SHIFT		6
+# define PV_VCONTROL_ODD_FIRST			BIT(5)
 # define PV_VCONTROL_INTERLACE			BIT(4)
 # define PV_VCONTROL_CONTINUOUS			BIT(1)
 # define PV_VCONTROL_VIDEN			BIT(0)
-- 
2.9.3