diff --git a/src/mainboard/google/zork/Kconfig b/src/mainboard/google/zork/Kconfig
index c4a8f330bd..24c49c1492 100644
--- a/src/mainboard/google/zork/Kconfig
+++ b/src/mainboard/google/zork/Kconfig
@@ -244,13 +244,13 @@ config VBOOT_STARTS_IN_BOOTBLOCK
 
 config EFS_SPI_READ_MODE
 	int
-	default 4 if EM100
-	default 2
+	default 0 if EM100 # Normal read mode
+	default 2          # Dual IO (1-1-2)
 
 config EFS_SPI_SPEED
 	int
-	default 3 if EM100
-	default 0
+	default 3 if EM100 # 16.66 MHz
+	default 0          # 66.66 MHz
 
 config EFS_SPI_MICRON_FLAG
 	int