gpu: imx: fix support for interlaced modes

The support for interlaced video modes seems to be broken; we don't use
anything other than the vtotal/htotal from the timing information to
define the various sync counters.

Freescale patches for interlaced video support contain an alternative
sync counter setup, which we include here.  This setup produces the
hsync and vsync via the normal counter 2 and 3, but moves the display
enable signal from counter 5 to counter 6.  Therefore, we need to
change the display controller setup as well.

The corresponding Freescale patches for this change are:
  iMX6-HDMI-support-interlaced-display-mode.patch
  IPU-fine-tuning-the-interlace-display-timing-for-CEA.patch

This produces a working interlace format output from the IPU.

Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/gpu/ipu-v3/ipu-dc.c

@@ -183,12 +183,19 @@ int ipu_dc_init_sync(struct ipu_dc *dc, struct ipu_di *di, bool interlaced,
 	}
 
 	if (interlaced) {
-		dc_link_event(dc, DC_EVT_NL, 0, 3);
-		dc_link_event(dc, DC_EVT_EOL, 0, 2);
-		dc_link_event(dc, DC_EVT_NEW_DATA, 0, 1);
+		int addr;
+
+		if (dc->di)
+			addr = 1;
+		else
+			addr = 0;
+
+		dc_link_event(dc, DC_EVT_NL, addr, 3);
+		dc_link_event(dc, DC_EVT_EOL, addr, 2);
+		dc_link_event(dc, DC_EVT_NEW_DATA, addr, 1);
 
 		/* Init template microcode */
-		dc_write_tmpl(dc, 0, WROD(0), 0, map, SYNC_WAVE, 0, 8, 1);
+		dc_write_tmpl(dc, addr, WROD(0), 0, map, SYNC_WAVE, 0, 6, 1);
 	} else {
 		if (dc->di) {
 			dc_link_event(dc, DC_EVT_NL, 2, 3);

drivers/gpu/ipu-v3/ipu-di.c

@@ -71,6 +71,10 @@ enum di_sync_wave {
 	DI_SYNC_HSYNC = 3,
 	DI_SYNC_VSYNC = 4,
 	DI_SYNC_DE = 6,
+
+	DI_SYNC_CNT1 = 2,	/* counter >= 2 only */
+	DI_SYNC_CNT4 = 5,	/* counter >= 5 only */
+	DI_SYNC_CNT5 = 6,	/* counter >= 6 only */
 };
 
 #define SYNC_WAVE 0
@@ -211,66 +215,59 @@ static void ipu_di_sync_config_interlaced(struct ipu_di *di,
 		sig->mode.hback_porch + sig->mode.hfront_porch;
 	u32 v_total = sig->mode.vactive + sig->mode.vsync_len +
 		sig->mode.vback_porch + sig->mode.vfront_porch;
-	u32 reg;
 	struct di_sync_config cfg[] = {
 		{
-			.run_count = h_total / 2 - 1,
-			.run_src = DI_SYNC_CLK,
+			/* 1: internal VSYNC for each frame */
+			.run_count = v_total * 2 - 1,
+			.run_src = 3,			/* == counter 7 */
 		}, {
-			.run_count = h_total - 11,
+			/* PIN2: HSYNC waveform */
+			.run_count = h_total - 1,
 			.run_src = DI_SYNC_CLK,
-			.cnt_down = 4,
+			.cnt_polarity_gen_en = 1,
+			.cnt_polarity_trigger_src = DI_SYNC_CLK,
+			.cnt_down = sig->mode.hsync_len * 2,
 		}, {
-			.run_count = v_total * 2 - 1,
-			.run_src = DI_SYNC_INT_HSYNC,
-			.offset_count = 1,
-			.offset_src = DI_SYNC_INT_HSYNC,
-			.cnt_down = 4,
+			/* PIN3: VSYNC waveform */
+			.run_count = v_total - 1,
+			.run_src = 4,			/* == counter 7 */
+			.cnt_polarity_gen_en = 1,
+			.cnt_polarity_trigger_src = 4,	/* == counter 7 */
+			.cnt_down = sig->mode.vsync_len * 2,
+			.cnt_clr_src = DI_SYNC_CNT1,
 		}, {
-			.run_count = v_total / 2 - 1,
+			/* 4: Field */
+			.run_count = v_total / 2,
 			.run_src = DI_SYNC_HSYNC,
-			.offset_count = sig->mode.vback_porch,
-			.offset_src = DI_SYNC_HSYNC,
+			.offset_count = h_total / 2,
+			.offset_src = DI_SYNC_CLK,
 			.repeat_count = 2,
-			.cnt_clr_src = DI_SYNC_VSYNC,
+			.cnt_clr_src = DI_SYNC_CNT1,
 		}, {
+			/* 5: Active lines */
 			.run_src = DI_SYNC_HSYNC,
-			.repeat_count = sig->mode.vactive / 2,
-			.cnt_clr_src = 4,
-		}, {
-			.run_count = v_total - 1,
-			.run_src = DI_SYNC_HSYNC,
-		}, {
-			.run_count = v_total / 2 - 1,
-			.run_src = DI_SYNC_HSYNC,
-			.offset_count = 9,
+			.offset_count = (sig->mode.vsync_len +
+					 sig->mode.vback_porch) / 2,
 			.offset_src = DI_SYNC_HSYNC,
-			.repeat_count = 2,
-			.cnt_clr_src = DI_SYNC_VSYNC,
+			.repeat_count = sig->mode.vactive / 2,
+			.cnt_clr_src = DI_SYNC_CNT4,
 		}, {
+			/* 6: Active pixel, referenced by DC */
 			.run_src = DI_SYNC_CLK,
-			.offset_count = sig->mode.hback_porch,
+			.offset_count = sig->mode.hsync_len +
+					sig->mode.hback_porch,
 			.offset_src = DI_SYNC_CLK,
 			.repeat_count = sig->mode.hactive,
-			.cnt_clr_src = 5,
+			.cnt_clr_src = DI_SYNC_CNT5,
 		}, {
-			.run_count = v_total - 1,
-			.run_src = DI_SYNC_INT_HSYNC,
-			.offset_count = v_total / 2,
-			.offset_src = DI_SYNC_INT_HSYNC,
-			.cnt_clr_src = DI_SYNC_HSYNC,
-			.cnt_down = 4,
+			/* 7: Half line HSYNC */
+			.run_count = h_total / 2 - 1,
+			.run_src = DI_SYNC_CLK,
 		}
 	};
 
 	ipu_di_sync_config(di, cfg, 0, ARRAY_SIZE(cfg));
 
-	/* set gentime select and tag sel */
-	reg = ipu_di_read(di, DI_SW_GEN1(9));
-	reg &= 0x1FFFFFFF;
-	reg |= (3 - 1) << 29 | 0x00008000;
-	ipu_di_write(di, reg, DI_SW_GEN1(9));
-
 	ipu_di_write(di, v_total / 2 - 1, DI_SCR_CONF);
 }
 
@@ -605,10 +602,8 @@ int ipu_di_init_sync_panel(struct ipu_di *di, struct ipu_di_signal_cfg *sig)
 
 		/* set y_sel = 1 */
 		di_gen |= 0x10000000;
-		di_gen |= DI_GEN_POLARITY_5;
-		di_gen |= DI_GEN_POLARITY_8;
 
-		vsync_cnt = 7;
+		vsync_cnt = 3;
 	} else {
 		ipu_di_sync_config_noninterlaced(di, sig, div);