diff --git a/drivers/gpu/drm/radeon/radeon_atombios.c b/drivers/gpu/drm/radeon/radeon_atombios.c
index 6df7bd569495..3bc2bcdf5308 100644
--- a/drivers/gpu/drm/radeon/radeon_atombios.c
+++ b/drivers/gpu/drm/radeon/radeon_atombios.c
@@ -1032,21 +1032,18 @@ bool radeon_atombios_sideport_present(struct radeon_device *rdev)
 	u8 frev, crev;
 	u16 data_offset;
 
+	/* sideport is AMD only */
+	if (rdev->family == CHIP_RS600)
+		return false;
+
 	if (atom_parse_data_header(mode_info->atom_context, index, NULL,
 				   &frev, &crev, &data_offset)) {
 		igp_info = (union igp_info *)(mode_info->atom_context->bios +
 				      data_offset);
 		switch (crev) {
 		case 1:
-			/* AMD IGPS */
-			if ((rdev->family == CHIP_RS690) ||
-			    (rdev->family == CHIP_RS740)) {
-				if (igp_info->info.ulBootUpMemoryClock)
-					return true;
-			} else {
-				if (igp_info->info.ucMemoryType & 0xf0)
-					return true;
-			}
+			if (igp_info->info.ulBootUpMemoryClock)
+				return true;
 			break;
 		case 2:
 			if (igp_info->info_2.ucMemoryType & 0x0f)
diff --git a/drivers/gpu/drm/radeon/radeon_combios.c b/drivers/gpu/drm/radeon/radeon_combios.c
index cd2a6c254e3e..5e1474cde4b4 100644
--- a/drivers/gpu/drm/radeon/radeon_combios.c
+++ b/drivers/gpu/drm/radeon/radeon_combios.c
@@ -693,6 +693,10 @@ bool radeon_combios_sideport_present(struct radeon_device *rdev)
 	struct drm_device *dev = rdev->ddev;
 	u16 igp_info;
 
+	/* sideport is AMD only */
+	if (rdev->family == CHIP_RS400)
+		return false;
+
 	igp_info = combios_get_table_offset(dev, COMBIOS_INTEGRATED_SYSTEM_INFO_TABLE);
 
 	if (igp_info) {
diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 85cd911952c1..cc05b230d7ef 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -696,7 +696,6 @@ void rs600_mc_init(struct radeon_device *rdev)
 	rdev->mc.igp_sideport_enabled = radeon_atombios_sideport_present(rdev);
 	base = RREG32_MC(R_000004_MC_FB_LOCATION);
 	base = G_000004_MC_FB_START(base) << 16;
-	rdev->mc.igp_sideport_enabled = radeon_atombios_sideport_present(rdev);
 	radeon_vram_location(rdev, &rdev->mc, base);
 	rdev->mc.gtt_base_align = 0;
 	radeon_gtt_location(rdev, &rdev->mc);
diff --git a/drivers/gpu/drm/radeon/rs690.c b/drivers/gpu/drm/radeon/rs690.c
index 6fbb874583f4..3e3f75718be3 100644
--- a/drivers/gpu/drm/radeon/rs690.c
+++ b/drivers/gpu/drm/radeon/rs690.c
@@ -159,8 +159,8 @@ void rs690_mc_init(struct radeon_device *rdev)
 	rdev->mc.visible_vram_size = rdev->mc.aper_size;
 	base = RREG32_MC(R_000100_MCCFG_FB_LOCATION);
 	base = G_000100_MC_FB_START(base) << 16;
-	rs690_pm_info(rdev);
 	rdev->mc.igp_sideport_enabled = radeon_atombios_sideport_present(rdev);
+	rs690_pm_info(rdev);
 	radeon_vram_location(rdev, &rdev->mc, base);
 	rdev->mc.gtt_base_align = rdev->mc.gtt_size - 1;
 	radeon_gtt_location(rdev, &rdev->mc);