[coreboot-gerrit] Change in coreboot[master]: drivers/analogix: fixup the video banking area timing to meet chip

[jitao shi (Code Review)]

jitao shi has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/39026 )

Change subject: drivers/analogix: fixup the video banking area timing to meet chip
......................................................................

drivers/analogix: fixup the video banking area timing to meet chip

Fixup HFP/HBP/HSYNC meet the chip (must larger than 8 and even number)

BUG=b:149051882
BRANCH=kukui
TEST=None

Change-Id: I3715fa854649f20fbef4e0bdfce59ebfa1f5f2b5
Signed-off-by: Jitao Shi 
---
M src/drivers/analogix/anx7625/anx7625.c
1 file changed, 118 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/26/39026/1

diff --git a/src/drivers/analogix/anx7625/anx7625.c b/src/drivers/analogix/anx7625/anx7625.c
index d2d09d8..10aa8b5 100644
--- a/src/drivers/analogix/anx7625/anx7625.c
+++ b/src/drivers/analogix/anx7625/anx7625.c
@@ -827,6 +827,119 @@
    	dt->vactive, dt->vsync_len, dt->vfront_porch, dt->vback_porch);
 }

+static void anx7625_modify_edid(struct edid *edid,
+			       struct display_timing *dt)
+{
+	u32 hsync, hfp, hbp, hactive, hblanking, htotal, vtotal;
+	u32 adj_hsync, adj_hfp, adj_hbp, adj_hblanking, delta_adj;
+	u32 vref, adj_clock;
+
+	hactive = dt->hactive;
+	hfp = dt->hfront_porch;
+	hbp = dt->hback_porch;
+	hsync = dt->hsync_len;
+	hblanking = hfp + hbp + hsync;
+	htotal = hactive + hfp + hbp + hsync;
+	vtotal = dt->vactive + dt->vsync_len +
+		 dt->vfront_porch + dt->vback_porch;
+
+	ANXINFO("before mode fixup\n");
+	ANXINFO("hsync(%d),hfp(%d),hbp(%d),clock(%d)\n",
+		hsync,
+		hfp,
+		hbp,
+		dt->pixelclock);
+
+	adj_hfp = hfp;
+	adj_hsync = hsync;
+	adj_hbp = hbp;
+	adj_hblanking = hblanking;
+
+	/* plus 1 if hfp is odd */
+	if (hfp & 0x1) {
+		adj_hfp = hfp + 1;
+		adj_hblanking += 1;
+	}
+
+	/* minus 1 if hbp is odd */
+	if (hbp & 0x1) {
+		adj_hbp = hbp - 1;
+		adj_hblanking -= 1;
+	}
+
+	/* plus 1 if hsync is odd */
+	if (hsync & 0x1) {
+		if (adj_hblanking < hblanking)
+			adj_hsync = hsync + 1;
+		else
+			adj_hsync = hsync - 1;
+	}
+
+	/*
+	 * once illegal timing detected, use default HFP, HSYNC, HBP
+	 */
+	if ((hblanking < HBLANKING_MIN) || (hfp < HP_MIN && hbp < HP_MIN))
+	{
+		adj_hsync = SYNC_LEN_DEF;
+		adj_hfp = HFP_HBP_DEF;
+		adj_hbp = HFP_HBP_DEF;
+		vref = dt->pixelclock * 1000 / (htotal * vtotal);
+		if (hblanking < HBLANKING_MIN) {
+			delta_adj = HBLANKING_MIN - hblanking;
+			adj_clock = vref * delta_adj * vtotal;
+			dt->pixelclock += DIV_ROUND_UP(adj_clock, 1000);
+		} else {
+			delta_adj = hblanking - HBLANKING_MIN;
+			adj_clock = vref * delta_adj * vtotal;
+			dt->pixelclock -= DIV_ROUND_UP(adj_clock, 1000);
+		}
+
+		ANXINFO("warn: illegal hblanking timing, use default.\n");
+		ANXINFO("warn: hfp(%d),hbp(%d),hsync(%d).\n", hfp, hbp, hsync);
+	} else if (adj_hfp < HP_MIN) {
+		/* adjust hfp if hfp less than HP_MIN */
+		delta_adj = HP_MIN - adj_hfp;
+		adj_hfp = HP_MIN;
+
+		/*
+		 * balance total HBlanking pixel, if HBP hasn't enough space,
+		 * adjust HSYNC length, otherwize adjust HBP
+		 */
+		if ((adj_hbp - delta_adj) < HP_MIN)
+			/* hbp not enough space */
+			adj_hsync -= delta_adj;
+		else
+			adj_hbp -= delta_adj;
+	} else if (adj_hbp < HP_MIN) {
+		delta_adj = HP_MIN - adj_hbp;
+		adj_hbp = HP_MIN;
+
+		/*
+		 * balance total HBlanking pixel, if HBP hasn't enough space,
+		 * adjust HSYNC length, otherwize adjust HBP
+		 */
+		if ((adj_hfp - delta_adj) < HP_MIN)
+			/* hbp not enough space */
+			adj_hsync -= delta_adj;
+		else
+			adj_hfp -= delta_adj;
+	}
+
+	ANXINFO("after mode fixup\n");
+	ANXINFO("hsync(%d),hfp(%d),hbp(%d),clock(%d)\n",
+		adj_hsync,
+		adj_hfp,
+		adj_hbp,
+		dt->pixelclock);
+
+	/* reconstructure EDID */
+	edid->mode.hspw = adj_hsync;
+	edid->mode.hso = adj_hfp + edid->mode.hborder;
+	edid->mode.hbl = adj_hbp + edid->mode.hso +
+			 edid->mode.hspw + edid->mode.hborder;
+	edid->mode.pixel_clock = dt->pixelclock;
+}
+
 int anx7625_dp_start(uint8_t bus, const struct edid *edid)
 {
    int ret;
@@ -847,6 +960,7 @@
 {
    int block_num;
    int ret;
+	struct display_timing dtiming;
    u8 edid[FOUR_BLOCK_SIZE];

block_num = sp_tx_edid_read(bus, edid, FOUR_BLOCK_SIZE);
@@ -861,6 +975,10 @@
    	return -1;
    }

+	anx7625_parse_edid(out, &dtiming);
+
+	anx7625_modify_edid(out, &dtiming);
+
    return 0;
 }