diff --git a/src/board/system76/darp7/board.mk b/src/board/system76/darp7/board.mk
index 4bcb47d..33fe68a 100644
--- a/src/board/system76/darp7/board.mk
+++ b/src/board/system76/darp7/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# Use S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=15in_102
 
diff --git a/src/board/system76/darp8/board.mk b/src/board/system76/darp8/board.mk
index 143d150..1e3d4d4 100644
--- a/src/board/system76/darp8/board.mk
+++ b/src/board/system76/darp8/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# Use S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=15in_102
 
diff --git a/src/board/system76/galp5/board.mk b/src/board/system76/galp5/board.mk
index d40deba..c206e4b 100644
--- a/src/board/system76/galp5/board.mk
+++ b/src/board/system76/galp5/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# Use S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=14in_83
 
diff --git a/src/board/system76/galp6/board.mk b/src/board/system76/galp6/board.mk
index 5874eaf..1099fae 100644
--- a/src/board/system76/galp6/board.mk
+++ b/src/board/system76/galp6/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# Use S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=14in_83
 
diff --git a/src/board/system76/gaze17-3050/board.mk b/src/board/system76/gaze17-3050/board.mk
index 749258a..ded22c1 100644
--- a/src/board/system76/gaze17-3050/board.mk
+++ b/src/board/system76/gaze17-3050/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# FIXME: Use S3 instead of S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=15in_102
 
diff --git a/src/board/system76/gaze17-3060/board.mk b/src/board/system76/gaze17-3060/board.mk
index de38378..4d002bc 100644
--- a/src/board/system76/gaze17-3060/board.mk
+++ b/src/board/system76/gaze17-3060/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# FIXME: Use S3 instead of S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=15in_102
 
diff --git a/src/board/system76/lemp10/board.mk b/src/board/system76/lemp10/board.mk
index db71b22..2832a3c 100644
--- a/src/board/system76/lemp10/board.mk
+++ b/src/board/system76/lemp10/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# Use S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=14in_83
 
diff --git a/src/board/system76/lemp11/board.mk b/src/board/system76/lemp11/board.mk
index 7f2862b..296f740 100644
--- a/src/board/system76/lemp11/board.mk
+++ b/src/board/system76/lemp11/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# Use S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=14in_83
 
diff --git a/src/board/system76/oryp9/board.mk b/src/board/system76/oryp9/board.mk
index 974cfbe..e92e571 100644
--- a/src/board/system76/oryp9/board.mk
+++ b/src/board/system76/oryp9/board.mk
@@ -9,9 +9,6 @@ CONFIG_EC_ITE_IT5570E=y
 # Enable eSPI
 CONFIG_BUS_ESPI=y
 
-# FIXME: Use S3 instead of S0ix
-CFLAGS+=-DUSE_S0IX=1
-
 # Include keyboard
 KEYBOARD=15in_102