2 files changed, 83 insertions, 0 deletions

diff --git a/src/northbridge/intel/sandybridge/gma.c b/src/northbridge/intel/sandybridge/gma.c
index d271a1afcb..a01fe9f771 100644
--- a/src/northbridge/intel/sandybridge/gma.c
+++ b/src/northbridge/intel/sandybridge/gma.c
@@ -21,6 +21,7 @@
 #include <console/console.h>
 #include <bootmode.h>
 #include <delay.h>
+#include <string.h>
 #include <device/device.h>
 #include <device/pci.h>
 #include <device/pci_ids.h>
diff --git a/src/northbridge/intel/sandybridge/gma_ivybridge_lvds.c b/src/northbridge/intel/sandybridge/gma_ivybridge_lvds.c
index 1f53a74b5f..ff877ffcb6 100644
--- a/src/northbridge/intel/sandybridge/gma_ivybridge_lvds.c
+++ b/src/northbridge/intel/sandybridge/gma_ivybridge_lvds.c
@@ -26,13 +26,64 @@
 
 #include <drivers/intel/gma/edid.h>
 #include <drivers/intel/gma/i915.h>
+#include <drivers/intel/gma/intel_bios.h>
 #include "gma.h"
 #include "chip.h"
 #include <pc80/vga.h>
 #include <pc80/vga_io.h>
+#include <device/pci_def.h>
+#include <device/pci_rom.h>
 
 #if IS_ENABLED(CONFIG_MAINBOARD_DO_NATIVE_VGA_INIT)
 
+static size_t generate_vbt(const struct northbridge_intel_sandybridge_config *conf,
+			   void *vbt)
+{
+	struct vbt_header *head = vbt;
+	struct bdb_header *bdb_head;
+	struct bdb_general_features *genfeat;
+	u8 *ptr;
+
+	memset(head, 0, sizeof (*head));
+
+	memcpy(head->signature, "$VBT SNB/IVB-MOBILE ", 20);
+	head->version = 100;
+	head->header_size = sizeof (*head);
+	head->bdb_offset = sizeof (*head);
+
+	bdb_head = (struct bdb_header *) (head + 1);
+	memset(bdb_head, 0, sizeof (*bdb_head));
+	memcpy(bdb_head->signature, "BIOS_DATA_BLOCK ", 16);
+	bdb_head->version = 0xa8;
+	bdb_head->header_size = sizeof (*bdb_head);
+
+	ptr = (u8 *) (bdb_head + 1);
+
+	ptr[0] = BDB_GENERAL_FEATURES;
+	ptr[1] = sizeof (*genfeat);
+	ptr[2] = sizeof (*genfeat) >> 8;
+	ptr += 3;
+
+	genfeat = (struct bdb_general_features *) ptr;
+	memset(genfeat, 0, sizeof (*genfeat));
+	genfeat->panel_fitting = 3;
+	genfeat->flexaim = 1;
+	genfeat->download_ext_vbt = 1;
+	genfeat->enable_ssc = conf->gpu_use_spread_spectrum_clock;
+	genfeat->ssc_freq = !conf->gpu_link_frequency_270_mhz;
+	genfeat->rsvd10 = 0x4;
+	genfeat->legacy_monitor_detect = 1;
+	genfeat->int_crt_support = 1;
+	genfeat->dp_ssc_enb = 1;
+
+	ptr += sizeof (*genfeat);
+
+	bdb_head->bdb_size = ptr - (u8 *)bdb_head;
+	head->vbt_size = ptr - (u8 *)head;
+	head->vbt_checksum = 0;
+	return ptr - (u8 *)head;
+}
+
 static void link_train(u32 mmio)
 {
 	write32(mmio+0xf000c,0x40);
@@ -509,6 +560,37 @@ int i915lightup(const struct northbridge_intel_sandybridge_config *info,
 	memset ((void *) lfb, 0, edid.x_resolution * edid.y_resolution * 4);
 	set_vbe_mode_info_valid(&edid, lfb);
 #endif
+
+	/* Linux relies on VBT for panel info.  */
+	optionrom_header_t *oh = (void *)PCI_VGA_RAM_IMAGE_START;
+	optionrom_pcir_t *pcir;
+	size_t vbt_size;
+	size_t fake_oprom_size;
+	struct device *dev;
+
+	dev = dev_find_slot(0, PCI_DEVFN(2, 0));
+
+	memset(oh, 0, 8192);
+
+	oh->signature = OPROM_SIGNATURE;
+	oh->pcir_offset = 0x40;
+	oh->vbt_offset = 0x80;
+
+	pcir = (void *)(PCI_VGA_RAM_IMAGE_START + 0x40);
+	pcir->signature = 0x52494350;	// PCIR
+	pcir->vendor = dev->vendor;
+	pcir->device = dev->device;
+	pcir->length = sizeof(*pcir);
+	pcir->revision = dev->class;
+	pcir->classcode[0] = dev->class >> 8;
+	pcir->classcode[1] = dev->class >> 16;
+	pcir->classcode[2] = dev->class >> 24;
+	pcir->indicator = 0x80;
+
+	vbt_size = generate_vbt (info, (void *)(PCI_VGA_RAM_IMAGE_START + 0x80));
+	fake_oprom_size = (0x80 + vbt_size + 511) / 512;
+	oh->size = fake_oprom_size;
+	pcir->imagelength = fake_oprom_size;
 	return 1;
 }