1 files changed, 71 insertions, 6 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
index 9d989c9f5da4..c7a8d517ce81 100644
--- a/drivers/gpu/drm/i915/display/intel_bios.c
+++ b/drivers/gpu/drm/i915/display/intel_bios.c
@@ -2335,6 +2335,63 @@ bool intel_bios_is_valid_vbt(const void *buf, size_t size)
 	return vbt;
 }
 
+static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915)
+{
+	u32 count, data, found, store = 0;
+	u32 static_region, oprom_offset;
+	u32 oprom_size = 0x200000;
+	u16 vbt_size;
+	u32 *vbt;
+
+	static_region = intel_uncore_read(&i915->uncore, SPI_STATIC_REGIONS);
+	static_region &= OPTIONROM_SPI_REGIONID_MASK;
+	intel_uncore_write(&i915->uncore, PRIMARY_SPI_REGIONID, static_region);
+
+	oprom_offset = intel_uncore_read(&i915->uncore, OROM_OFFSET);
+	oprom_offset &= OROM_OFFSET_MASK;
+
+	for (count = 0; count < oprom_size; count += 4) {
+		intel_uncore_write(&i915->uncore, PRIMARY_SPI_ADDRESS, oprom_offset + count);
+		data = intel_uncore_read(&i915->uncore, PRIMARY_SPI_TRIGGER);
+
+		if (data == *((const u32 *)"$VBT")) {
+			found = oprom_offset + count;
+			break;
+		}
+	}
+
+	if (count >= oprom_size)
+		goto err_not_found;
+
+	/* Get VBT size and allocate space for the VBT */
+	intel_uncore_write(&i915->uncore, PRIMARY_SPI_ADDRESS, found +
+		   offsetof(struct vbt_header, vbt_size));
+	vbt_size = intel_uncore_read(&i915->uncore, PRIMARY_SPI_TRIGGER);
+	vbt_size &= 0xffff;
+
+	vbt = kzalloc(round_up(vbt_size, 4), GFP_KERNEL);
+	if (!vbt)
+		goto err_not_found;
+
+	for (count = 0; count < vbt_size; count += 4) {
+		intel_uncore_write(&i915->uncore, PRIMARY_SPI_ADDRESS, found + count);
+		data = intel_uncore_read(&i915->uncore, PRIMARY_SPI_TRIGGER);
+		*(vbt + store++) = data;
+	}
+
+	if (!intel_bios_is_valid_vbt(vbt, vbt_size))
+		goto err_free_vbt;
+
+	drm_dbg_kms(&i915->drm, "Found valid VBT in SPI flash\n");
+
+	return (struct vbt_header *)vbt;
+
+err_free_vbt:
+	kfree(vbt);
+err_not_found:
+	return NULL;
+}
+
 static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915)
 {
 	struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
@@ -2384,6 +2441,8 @@ static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915)
 
 	pci_unmap_rom(pdev, oprom);
 
+	drm_dbg_kms(&i915->drm, "Found valid VBT in PCI ROM\n");
+
 	return vbt;
 
 err_free_vbt:
@@ -2418,17 +2477,23 @@ void intel_bios_init(struct drm_i915_private *i915)
 
 	init_vbt_defaults(i915);
 
-	/* If the OpRegion does not have VBT, look in PCI ROM. */
+	/*
+	 * If the OpRegion does not have VBT, look in SPI flash through MMIO or
+	 * PCI mapping
+	 */
+	if (!vbt && IS_DGFX(i915)) {
+		oprom_vbt = spi_oprom_get_vbt(i915);
+		vbt = oprom_vbt;
+	}
+
 	if (!vbt) {
 		oprom_vbt = oprom_get_vbt(i915);
-		if (!oprom_vbt)
-			goto out;
-
 		vbt = oprom_vbt;
-
-		drm_dbg_kms(&i915->drm, "Found valid VBT in PCI ROM\n");
 	}
 
+	if (!vbt)
+		goto out;
+
 	bdb = get_bdb_header(vbt);
 	i915->vbt.version = bdb->version;