diff --git a/scripts/om-fwupgradecfg-gen.sh b/scripts/om-fwupgradecfg-gen.sh
index 4a7094055f..915fbd05ab 100755
--- a/scripts/om-fwupgradecfg-gen.sh
+++ b/scripts/om-fwupgradecfg-gen.sh
@@ -23,7 +23,6 @@ case $CE_TYPE in
 	OM2P)
 		MAX_PART_SIZE=7168
 		KERNEL_FLASH_ADDR=0x1c0000
-		FLASH_BS=262144
 		MD5_SKIP_BLOCKS=4
 		SIZE_FACTOR=1
 		SIZE_FORMAT="%d"
@@ -31,7 +30,6 @@ case $CE_TYPE in
 	OM5P|OM5PAC|MR600|MR900|MR1750|A60)
 		MAX_PART_SIZE=7808
 		KERNEL_FLASH_ADDR=0xb0000
-		FLASH_BS=65536
 		MD5_SKIP_BLOCKS=4
 		SIZE_FACTOR=1
 		SIZE_FORMAT="%d"
@@ -39,7 +37,6 @@ case $CE_TYPE in
 	A42)
 		MAX_PART_SIZE=15616
 		KERNEL_FLASH_ADDR=0x180000
-		FLASH_BS=65536
 		MD5_SKIP_BLOCKS=4
 		SIZE_FACTOR=1024
 		SIZE_FORMAT="0x%08x"
@@ -47,7 +44,6 @@ case $CE_TYPE in
 	A62)
 		MAX_PART_SIZE=15552
 		KERNEL_FLASH_ADDR=0x1a0000
-		FLASH_BS=65536
 		MD5_SKIP_BLOCKS=4
 		SIZE_FACTOR=1024
 		SIZE_FORMAT="0x%08x"
@@ -63,7 +59,7 @@ CHECK_BS=65536
 KERNEL_SIZE=$(stat -c%s "$KERNEL_PATH")
 KERNEL_MD5=$(mkhash md5 $KERNEL_PATH)
 KERNEL_SHA256=$(mkhash sha256 $KERNEL_PATH)
-KERNEL_PART_SIZE_KB=$(size=$(($KERNEL_SIZE / $FLASH_BS)); [ $(($size * $FLASH_BS)) -lt $KERNEL_SIZE ] && size=$(($size + 1)); echo $(($size * $FLASH_BS / 1024)))
+KERNEL_PART_SIZE_KB=$((KERNEL_SIZE / 1024))
 KERNEL_PART_SIZE=$(printf $SIZE_FORMAT $(($KERNEL_PART_SIZE_KB * $SIZE_FACTOR)))
 
 ROOTFS_FLASH_ADDR=$(addr=$(($KERNEL_FLASH_ADDR + ($KERNEL_PART_SIZE_KB * 1024))); printf "0x%x" $addr)