Change in coreboot[master]: drivers/intel/gma/vbt.c: Add GENERAL DEFINITIONS block to fake vbt

[Arthur Heymans (Code Review)]

Arthur Heymans has uploaded this change for review. ( https://review.coreboot.org/21448

Change subject: drivers/intel/gma/vbt.c: Add GENERAL DEFINITIONS block to fake vbt
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drivers/intel/gma/vbt.c: Add GENERAL DEFINITIONS block to fake vbt

This is needed for Linux (at least 4.12) to know on which DDC gmbus to
probe for VGA edid.

TESTED on dg43gt: Use NGI with a payload like grub that doesn't
override VBT (seavgabios) with a DVI-I to VGA adapter and observe that
Linux can properly modeset the display.

Change-Id: I5bce00d2e37d77c27cf0022c7dab3444c3699dcf
Signed-off-by: Arthur Heymans 
---
M src/drivers/intel/gma/vbt.c
1 file changed, 15 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/48/21448/1

diff --git a/src/drivers/intel/gma/vbt.c b/src/drivers/intel/gma/vbt.c
index c908eb4..ffb56e9 100644
--- a/src/drivers/intel/gma/vbt.c
+++ b/src/drivers/intel/gma/vbt.c
@@ -69,6 +69,21 @@

ptr += sizeof (*genfeat);

+	*ptr++ = BDB_GENERAL_DEFINITIONS;
+	*ptr++ = sizeof(struct bdb_general_definitions);
+	*ptr++ = sizeof(struct bdb_general_definitions) >> 8;
+	struct bdb_general_definitions *const gendef =
+		(struct bdb_general_definitions *)ptr;
+	if (IS_ENABLED(CONFIG_GFX_GMA_ANALOG_I2C_HDMI_B))
+		gendef->crt_ddc_gmbus_pin = GMBUS_PORT_DPB;
+	else if (IS_ENABLED(CONFIG_GFX_GMA_ANALOG_I2C_HDMI_C))
+		gendef->crt_ddc_gmbus_pin = GMBUS_PORT_DPC;
+	else if (IS_ENABLED(CONFIG_GFX_GMA_ANALOG_I2C_HDMI_D))
+		gendef->crt_ddc_gmbus_pin = GMBUS_PORT_DPD;
+	else
+		gendef->crt_ddc_gmbus_pin = GMBUS_PORT_VGADDC;
+	ptr += sizeof(*gendef);
+
    bdb_head->bdb_size = ptr - (u8 *)bdb_head;
    head->vbt_size = ptr - (u8 *)head;
    head->vbt_checksum = 0;