diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index b8c5c7d867bb..479970e2d822 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1298,7 +1298,7 @@ intel_subplatform(const struct intel_runtime_info *info, enum intel_platform p)
 {
 	const unsigned int pi = __platform_mask_index(info, p);
 
-	return info->platform_mask[pi] & ((1 << INTEL_SUBPLATFORM_BITS) - 1);
+	return info->platform_mask[pi] & INTEL_SUBPLATFORM_MASK;
 }
 
 static __always_inline bool
diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
index 8aaa0f8f6cfd..aeb28d589b2b 100644
--- a/drivers/gpu/drm/i915/intel_device_info.c
+++ b/drivers/gpu/drm/i915/intel_device_info.c
@@ -223,7 +223,7 @@ void intel_device_info_subplatform_init(struct drm_i915_private *i915)
 		}
 	}
 
-	GEM_BUG_ON(mask & ~INTEL_SUBPLATFORM_BITS);
+	GEM_BUG_ON(mask & ~INTEL_SUBPLATFORM_MASK);
 
 	RUNTIME_INFO(i915)->platform_mask[pi] |= mask;
 }
diff --git a/drivers/gpu/drm/i915/intel_device_info.h b/drivers/gpu/drm/i915/intel_device_info.h
index efd138761e14..d44f64b57b7a 100644
--- a/drivers/gpu/drm/i915/intel_device_info.h
+++ b/drivers/gpu/drm/i915/intel_device_info.h
@@ -93,7 +93,8 @@ enum intel_platform {
  * it is fine for the same bit to be used on multiple parent platforms.
  */
 
-#define INTEL_SUBPLATFORM_BITS (3)
+#define INTEL_SUBPLATFORM_BITS (2)
+#define INTEL_SUBPLATFORM_MASK (BIT(INTEL_SUBPLATFORM_BITS) - 1)
 
 /* HSW/BDW/SKL/KBL/CFL */
 #define INTEL_SUBPLATFORM_ULT	(0)