diff --git a/src/soc/intel/common/block/fast_spi/fast_spi.c b/src/soc/intel/common/block/fast_spi/fast_spi.c
index ed61c10..8dc173c 100644
--- a/src/soc/intel/common/block/fast_spi/fast_spi.c
+++ b/src/soc/intel/common/block/fast_spi/fast_spi.c
@@ -529,7 +529,7 @@
 	pci_dev_read_resources(dev);
 
 	/* Add SPI flash MMIO window as a reserved resource. */
-	mmio_resource(dev, 0, FLASH_BASE_ADDR / KiB, FLASH_MMIO_SIZE / KiB);
+	mmio_resource_kb(dev, 0, FLASH_BASE_ADDR / KiB, FLASH_MMIO_SIZE / KiB);
 }
 
 static struct device_operations fast_spi_dev_ops = {