diff --git a/Ryujinx.Graphics/Gal/Shader/GlslDecl.cs b/Ryujinx.Graphics/Gal/Shader/GlslDecl.cs
index 867f901604..d3284f9f55 100644
--- a/Ryujinx.Graphics/Gal/Shader/GlslDecl.cs
+++ b/Ryujinx.Graphics/Gal/Shader/GlslDecl.cs
@@ -9,6 +9,7 @@ namespace Ryujinx.Graphics.Gal.Shader
         public const int TessCoordAttrZ  = 0x2f8;
         public const int InstanceIdAttr  = 0x2f8;
         public const int VertexIdAttr    = 0x2fc;
+        public const int FaceAttr        = 0x3fc;
         public const int GlPositionWAttr = 0x7c;
 
         public const int MaxUboSize = 1024;
@@ -208,7 +209,8 @@ namespace Ryujinx.Graphics.Gal.Shader
                 {
                     //This is a built-in input variable.
                     if (Abuf.Offs == VertexIdAttr ||
-                        Abuf.Offs == InstanceIdAttr)
+                        Abuf.Offs == InstanceIdAttr ||
+                        Abuf.Offs == FaceAttr)
                     {
                         break;
                     }
diff --git a/Ryujinx.Graphics/Gal/Shader/GlslDecompiler.cs b/Ryujinx.Graphics/Gal/Shader/GlslDecompiler.cs
index 87d448689b..f3075a504e 100644
--- a/Ryujinx.Graphics/Gal/Shader/GlslDecompiler.cs
+++ b/Ryujinx.Graphics/Gal/Shader/GlslDecompiler.cs
@@ -658,6 +658,14 @@ namespace Ryujinx.Graphics.Gal.Shader
                     case GlslDecl.TessCoordAttrZ: return "gl_TessCoord.z";
                 }
             }
+            else if (Decl.ShaderType == GalShaderType.Fragment)
+            {
+                switch (Abuf.Offs)
+                {
+                    //Note: It's a guess that Maxwell's face is 1 when gl_FrontFacing == true
+                    case GlslDecl.FaceAttr: return "(gl_FrontFacing ? 1 : 0)";
+                }
+            }
 
             return GetAttrTempName(Abuf);
         }
@@ -1084,7 +1092,8 @@ namespace Ryujinx.Graphics.Gal.Shader
             {
                 case ShaderIrOperAbuf Abuf:
                     return Abuf.Offs == GlslDecl.VertexIdAttr ||
-                           Abuf.Offs == GlslDecl.InstanceIdAttr
+                           Abuf.Offs == GlslDecl.InstanceIdAttr ||
+                           Abuf.Offs == GlslDecl.FaceAttr
                         ? OperType.I32
                         : OperType.F32;