From fe6eb0d5c638daf50ead6d3ced2fac36261aefe3 Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.com>
Date: Mon, 13 Jun 2022 16:48:00 +0200
Subject: drm/vc4: hdmi: Move pixel doubling from Pixelvalve to HDMI block
Git-commit: 3650062e4281ab28a6f8c9d59606d0a6266be736
Patch-mainline: v6.0-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225 jsc#PED-2849

With the change to 2 pixels/clock, the pixel doubling in the PV
results in doubling each pair of pixels, ie ABABCDCD instead of
AABBCCDD.

Move the pixel doubling to the HDMI block, however this means
that DBLCLK modes now fall foul of requiring even values for
all the horizontal timing parameters.
As both 480i and 576i fail this, attempt to fix up DBLCLK modes
that have odd timings values.

Fixes: 8323989140f3 ("drm/vc4: hdmi: Support the BCM2711 HDMI controllers")
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://lore.kernel.org/r/20220613144800.326124-34-maxime@cerno.tech
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/vc4/vc4_crtc.c |  4 +++-
 drivers/gpu/drm/vc4/vc4_hdmi.c | 34 ++++++++++++++++++++++++++++------
 2 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 6e1d75ff9440..029be98660b3 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -317,7 +317,9 @@ static void vc4_crtc_config_pv(struct drm_crtc *crtc, struct drm_encoder *encode
 	struct drm_crtc_state *crtc_state = crtc->state;
 	struct drm_display_mode *mode = &crtc_state->adjusted_mode;
 	bool interlace = mode->flags & DRM_MODE_FLAG_INTERLACE;
-	u32 pixel_rep = (mode->flags & DRM_MODE_FLAG_DBLCLK) ? 2 : 1;
+	bool is_hdmi = vc4_encoder->type == VC4_ENCODER_TYPE_HDMI0 ||
+		       vc4_encoder->type == VC4_ENCODER_TYPE_HDMI1;
+	u32 pixel_rep = ((mode->flags & DRM_MODE_FLAG_DBLCLK) && !is_hdmi) ? 2 : 1;
 	bool is_dsi = (vc4_encoder->type == VC4_ENCODER_TYPE_DSI0 ||
 		       vc4_encoder->type == VC4_ENCODER_TYPE_DSI1);
 	bool is_dsi1 = vc4_encoder->type == VC4_ENCODER_TYPE_DSI1;
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 9d48c6458bc4..6ab83296b0e4 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -79,6 +79,8 @@
 #define VC5_HDMI_VERTB_VSPO_SHIFT		16
 #define VC5_HDMI_VERTB_VSPO_MASK		VC4_MASK(29, 16)
 
+#define VC4_HDMI_MISC_CONTROL_PIXEL_REP_SHIFT	0
+#define VC4_HDMI_MISC_CONTROL_PIXEL_REP_MASK	VC4_MASK(3, 0)
 #define VC5_HDMI_MISC_CONTROL_PIXEL_REP_SHIFT	0
 #define VC5_HDMI_MISC_CONTROL_PIXEL_REP_MASK	VC4_MASK(3, 0)
 
@@ -992,6 +994,7 @@ static void vc4_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
 					mode->crtc_vsync_end,
 					VC4_HDMI_VERTB_VBP));
 	unsigned long flags;
+	u32 reg;
 
 	spin_lock_irqsave(&vc4_hdmi->hw_lock, flags);
 
@@ -1018,6 +1021,11 @@ static void vc4_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
 	HDMI_WRITE(HDMI_VERTB0, vertb_even);
 	HDMI_WRITE(HDMI_VERTB1, vertb);
 
+	reg = HDMI_READ(HDMI_MISC_CONTROL);
+	reg &= ~VC4_HDMI_MISC_CONTROL_PIXEL_REP_MASK;
+	reg |= VC4_SET_FIELD(pixel_rep - 1, VC4_HDMI_MISC_CONTROL_PIXEL_REP);
+	HDMI_WRITE(HDMI_MISC_CONTROL, reg);
+
 	spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags);
 }
 
@@ -1118,7 +1126,7 @@ static void vc5_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
 
 	reg = HDMI_READ(HDMI_MISC_CONTROL);
 	reg &= ~VC5_HDMI_MISC_CONTROL_PIXEL_REP_MASK;
-	reg |= VC4_SET_FIELD(0, VC5_HDMI_MISC_CONTROL_PIXEL_REP);
+	reg |= VC4_SET_FIELD(pixel_rep - 1, VC5_HDMI_MISC_CONTROL_PIXEL_REP);
 	HDMI_WRITE(HDMI_MISC_CONTROL, reg);
 
 	HDMI_WRITE(HDMI_CLOCK_STOP, 0);
@@ -1617,11 +1625,25 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
 	unsigned long long tmds_bit_rate;
 	int ret;
 
-	if (vc4_hdmi->variant->unsupported_odd_h_timings &&
-	    !(mode->flags & DRM_MODE_FLAG_DBLCLK) &&
-	    ((mode->hdisplay % 2) || (mode->hsync_start % 2) ||
-	     (mode->hsync_end % 2) || (mode->htotal % 2)))
-		return -EINVAL;
+	if (vc4_hdmi->variant->unsupported_odd_h_timings) {
+		if (mode->flags & DRM_MODE_FLAG_DBLCLK) {
+			/* Only try to fixup DBLCLK modes to get 480i and 576i
+			 * working.
+			 * A generic solution for all modes with odd horizontal
+			 * timing values seems impossible based on trying to
+			 * solve it for 1366x768 monitors.
+			 */
+			if ((mode->hsync_start - mode->hdisplay) & 1)
+				mode->hsync_start--;
+			if ((mode->hsync_end - mode->hsync_start) & 1)
+				mode->hsync_end--;
+		}
+
+		/* Now check whether we still have odd values remaining */
+		if ((mode->hdisplay % 2) || (mode->hsync_start % 2) ||
+		    (mode->hsync_end % 2) || (mode->htotal % 2))
+			return -EINVAL;
+	}
 
 	/*
 	 * The 1440p@60 pixel rate is in the same range than the first
-- 
2.38.1