diff --git a/drivers/gpu/drm/i915/display/intel_vga.c b/drivers/gpu/drm/i915/display/intel_vga.c
index 9cedeb8c2f4d..286a0bdd28c6 100644
--- a/drivers/gpu/drm/i915/display/intel_vga.c
+++ b/drivers/gpu/drm/i915/display/intel_vga.c
@@ -6,9 +6,10 @@
 #include <linux/pci.h>
 #include <linux/vgaarb.h>
 
-#include <drm/i915_drm.h>
 #include <video/vga.h>
 
+#include "soc/intel_gmch.h"
+
 #include "i915_drv.h"
 #include "i915_reg.h"
 #include "intel_de.h"
@@ -98,39 +99,12 @@ void intel_vga_reset_io_mem(struct drm_i915_private *i915)
 	vga_put(pdev, VGA_RSRC_LEGACY_IO);
 }
 
-static int
-intel_vga_set_state(struct drm_i915_private *i915, bool enable_decode)
-{
-	unsigned int reg = DISPLAY_VER(i915) >= 6 ? SNB_GMCH_CTRL : INTEL_GMCH_CTRL;
-	u16 gmch_ctrl;
-
-	if (pci_read_config_word(i915->gmch.pdev, reg, &gmch_ctrl)) {
-		drm_err(&i915->drm, "failed to read control word\n");
-		return -EIO;
-	}
-
-	if (!!(gmch_ctrl & INTEL_GMCH_VGA_DISABLE) == !enable_decode)
-		return 0;
-
-	if (enable_decode)
-		gmch_ctrl &= ~INTEL_GMCH_VGA_DISABLE;
-	else
-		gmch_ctrl |= INTEL_GMCH_VGA_DISABLE;
-
-	if (pci_write_config_word(i915->gmch.pdev, reg, gmch_ctrl)) {
-		drm_err(&i915->drm, "failed to write control word\n");
-		return -EIO;
-	}
-
-	return 0;
-}
-
 static unsigned int
 intel_vga_set_decode(struct pci_dev *pdev, bool enable_decode)
 {
 	struct drm_i915_private *i915 = pdev_to_i915(pdev);
 
-	intel_vga_set_state(i915, enable_decode);
+	intel_gmch_vga_set_state(i915, enable_decode);
 
 	if (enable_decode)
 		return VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM |
diff --git a/drivers/gpu/drm/i915/soc/intel_gmch.c b/drivers/gpu/drm/i915/soc/intel_gmch.c
index d5fbb7907725..6d0204942f7a 100644
--- a/drivers/gpu/drm/i915/soc/intel_gmch.c
+++ b/drivers/gpu/drm/i915/soc/intel_gmch.c
@@ -7,6 +7,7 @@
 #include <linux/pnp.h>
 
 #include <drm/drm_managed.h>
+#include <drm/i915_drm.h>
 
 #include "i915_drv.h"
 #include "intel_gmch.h"
@@ -142,3 +143,29 @@ void intel_gmch_bar_teardown(struct drm_i915_private *i915)
 	if (i915->gmch.mch_res.start)
 		release_resource(&i915->gmch.mch_res);
 }
+
+int intel_gmch_vga_set_state(struct drm_i915_private *i915, bool enable_decode)
+{
+	unsigned int reg = DISPLAY_VER(i915) >= 6 ? SNB_GMCH_CTRL : INTEL_GMCH_CTRL;
+	u16 gmch_ctrl;
+
+	if (pci_read_config_word(i915->gmch.pdev, reg, &gmch_ctrl)) {
+		drm_err(&i915->drm, "failed to read control word\n");
+		return -EIO;
+	}
+
+	if (!!(gmch_ctrl & INTEL_GMCH_VGA_DISABLE) == !enable_decode)
+		return 0;
+
+	if (enable_decode)
+		gmch_ctrl &= ~INTEL_GMCH_VGA_DISABLE;
+	else
+		gmch_ctrl |= INTEL_GMCH_VGA_DISABLE;
+
+	if (pci_write_config_word(i915->gmch.pdev, reg, gmch_ctrl)) {
+		drm_err(&i915->drm, "failed to write control word\n");
+		return -EIO;
+	}
+
+	return 0;
+}
diff --git a/drivers/gpu/drm/i915/soc/intel_gmch.h b/drivers/gpu/drm/i915/soc/intel_gmch.h
index bbc52dbab708..d0133eedc720 100644
--- a/drivers/gpu/drm/i915/soc/intel_gmch.h
+++ b/drivers/gpu/drm/i915/soc/intel_gmch.h
@@ -6,10 +6,13 @@
 #ifndef __INTEL_GMCH_H__
 #define __INTEL_GMCH_H__
 
+#include <linux/types.h>
+
 struct drm_i915_private;
 
 int intel_gmch_bridge_setup(struct drm_i915_private *i915);
 void intel_gmch_bar_setup(struct drm_i915_private *i915);
 void intel_gmch_bar_teardown(struct drm_i915_private *i915);
+int intel_gmch_vga_set_state(struct drm_i915_private *i915, bool enable_decode);
 
 #endif /* __INTEL_GMCH_H__ */