if (rdev->flags & RADEON_IS_IGP)
                rdev->config.evergreen.tile_config |= 1 << 4;
        else {
-               if ((mc_arb_ramcfg & NOOFBANK_MASK) >> NOOFBANK_SHIFT)
-                       rdev->config.evergreen.tile_config |= 1 << 4;
-               else
+               switch ((mc_arb_ramcfg & NOOFBANK_MASK) >> NOOFBANK_SHIFT) {
+               case 0: /* four banks */
                        rdev->config.evergreen.tile_config |= 0 << 4;
+                       break;
+               case 1: /* eight banks */
+                       rdev->config.evergreen.tile_config |= 1 << 4;
+                       break;
+               case 2: /* sixteen banks */
+               default:
+                       rdev->config.evergreen.tile_config |= 2 << 4;
+                       break;
+               }
        }
        rdev->config.evergreen.tile_config |= 0 << 8;
        rdev->config.evergreen.tile_config |=