[S] Change in coreboot[main]: soc/mediatek: Introduce mtk_edp_enable() to fix eDP init flow

[Yu-Ping Wu (Code Review)]

Yu-Ping Wu has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/86028?usp=email )

Change subject: soc/mediatek: Introduce mtk_edp_enable() to fix eDP init flow
......................................................................

soc/mediatek: Introduce mtk_edp_enable() to fix eDP init flow

In the current eDP initialization flow, eDP is configured and enabled
before display data pipe (DDP) initialization. The init flow is wrong,
because eDP should be enabled only after DDP is correctly set up. The
wrong flow may lead to garbage display between enabling eDP and
configuring DDP.

To fix the problem, the dptx_video_enable(true) call needs to be moved
after mtk_ddp_mode_set(). Introduce a new API mtk_edp_enable() for eDP
enablement, to be separated from the existing mtk_edp_init(). The fixed
eDP init flow is: mtk_edp_init -> mtk_ddp_mode_set -> mtk_edp_enable.

Change-Id: Ief847320caca1af1c6deb242dc224e7698a6603c
Signed-off-by: Yu-Ping Wu 
---
M src/soc/mediatek/common/display.c
M src/soc/mediatek/common/dp/dptx.c
M src/soc/mediatek/common/dp/include/soc/dptx_common.h
3 files changed, 34 insertions(+), 15 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/28/86028/1

diff --git a/src/soc/mediatek/common/display.c b/src/soc/mediatek/common/display.c
index a212805..3403bd8 100644
--- a/src/soc/mediatek/common/display.c
+++ b/src/soc/mediatek/common/display.c
@@ -37,7 +37,13 @@
    return NULL;
 }

-__weak int mtk_edp_init(struct edid *edid)
+__weak int mtk_edp_init(struct edid *edid, struct mtk_dp *mtk_dp);
+{
+	printk(BIOS_WARNING, "%s: Not supported\n", __func__);
+	return -1;
+}
+
+__weak int mtk_edp_enable(struct mtk_dp *mtk_dp)
 {
    printk(BIOS_WARNING, "%s: Not supported\n", __func__);
    return -1;
@@ -52,7 +58,8 @@

int mtk_display_init(void)
 {
-	struct edid edid;
+	struct edid edid = {0};
+	struct mtk_dp mtk_edp = {0};
    struct fb_info *info;
    const char *name;
    struct panel_description *panel = get_active_panel();
@@ -76,7 +83,7 @@

if (panel->disp_path == DISP_PATH_EDP) {
    	mdelay(200);
-		if (mtk_edp_init(&edid) < 0) {
+		if (mtk_edp_init(&edid, &mtk_edp) < 0) {
    		printk(BIOS_ERR, "%s: Failed to initialize eDP\n", __func__);
    		return -1;
    	}
@@ -120,6 +127,14 @@
    edid_set_framebuffer_bits_per_pixel(&edid, 32, 0);

mtk_ddp_mode_set(&edid, panel->disp_path);
+
+	if (panel->disp_path == DISP_PATH_EDP) {
+		if (mtk_edp_enable(mtk_edp) < 0) {
+			printk(BIOS_ERR, "%s: Failed to enable eDP\n", __func__);
+			return -1;
+		}
+	}
+
    info = fb_new_framebuffer_info_from_edid(&edid, (uintptr_t)0);
    if (info)
    	fb_set_orientation(info, panel->orientation);
diff --git a/src/soc/mediatek/common/dp/dptx.c b/src/soc/mediatek/common/dp/dptx.c
index b0afb89..1cc6337 100644
--- a/src/soc/mediatek/common/dp/dptx.c
+++ b/src/soc/mediatek/common/dp/dptx.c
@@ -478,29 +478,31 @@
    dptx_hal_hpd_int_en(mtk_dp, true);
 }

-int mtk_edp_init(struct edid *edid)
+int mtk_edp_init(struct edid *edid, struct mtk_dp *mtk_dp);
 {
-	struct mtk_dp mtk_edp;
+	dptx_init_variable(mtk_dp);
+	dptx_init_port(mtk_dp);

-	dptx_init_variable(&mtk_edp);
-	dptx_init_port(&mtk_edp);
-
-	if (!dptx_hal_hpd_high(&mtk_edp)) {
+	if (!dptx_hal_hpd_high(mtk_dp)) {
    	printk(BIOS_ERR, "HPD is low\n");
    	return -1;
    }

-	dptx_check_sinkcap(&mtk_edp);
+	dptx_check_sinkcap(mtk_dp);

-	if (dptx_get_edid(&mtk_edp, edid) != 0) {
+	if (dptx_get_edid(mtk_dp, edid) != 0) {
    	printk(BIOS_ERR, "Failed to get EDID\n");
    	return -1;
    }

-	dptx_set_trainingstart(&mtk_edp);
+	dptx_set_trainingstart(mtk_dp);
    dp_intf_config(edid);
-	dptx_video_config(&mtk_edp);
-	dptx_video_enable(&mtk_edp, true);
+	dptx_video_config(mtk_dp);

return 0;
 }
+
+int mtk_edp_enable(struct mtk_dp *mtk_dp)
+{
+	dptx_video_enable(mtk_dp, true);
+}
diff --git a/src/soc/mediatek/common/dp/include/soc/dptx_common.h b/src/soc/mediatek/common/dp/include/soc/dptx_common.h
index 1d7e135..e751618 100644
--- a/src/soc/mediatek/common/dp/include/soc/dptx_common.h
+++ b/src/soc/mediatek/common/dp/include/soc/dptx_common.h
@@ -211,7 +211,9 @@
    bool powered;
 };

-int mtk_edp_init(struct edid *edid);
+int mtk_edp_init(struct edid *edid, struct mtk_dp *mtk_dp);
+int mtk_edp_enable(struct mtk_dp *mtk_dp);
+
 bool dptx_auxread_dpcd(struct mtk_dp *mtk_dp, u8 cmd, u32 dpcd_addr,
    	       size_t length, u8 *rxbuf);
 bool dptx_auxwrite_dpcd(struct mtk_dp *mtk_dp, u8 cmd, u32 dpcd_addr,