diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 0fbc31134561b..c5349aaaf8740 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2579,6 +2579,7 @@ intel_info(const struct drm_i915_private *dev_priv)
 #define BXT_REVID_A0		0x0
 #define BXT_REVID_A1		0x1
 #define BXT_REVID_B0		0x3
+#define BXT_REVID_B_LAST	0x8
 #define BXT_REVID_C0		0x9
 
 #define IS_BXT_REVID(dev_priv, since, until) \
diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index d7be0d94ba4d1..07779d0c71e65 100644
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -421,8 +421,7 @@ static void __intel_uncore_early_sanitize(struct drm_i915_private *dev_priv,
 				   GT_FIFO_CTL_RC6_POLICY_STALL);
 	}
 
-	/* Enable Decoupled MMIO only on BXT C stepping onwards */
-	if (!IS_BXT_REVID(dev_priv, BXT_REVID_C0, REVID_FOREVER))
+	if (IS_BXT_REVID(dev_priv, 0, BXT_REVID_B_LAST))
 		info->has_decoupled_mmio = false;
 
 	intel_uncore_forcewake_reset(dev_priv, restore_forcewake);