Fix typo: firstly -> first.

Signed-off-by: Vagrant Cascadian <vagrant@debian.org>
Acked-by: Marek Vasut <marex@denx.de>
diff --git a/drivers/block/ahci.c b/drivers/block/ahci.c
index 734fdcc..5efa821 100644
--- a/drivers/block/ahci.c
+++ b/drivers/block/ahci.c
@@ -818,7 +818,7 @@
 	if (!ataid[pccb->target]) {
 		printf("scsi_ahci: SCSI READ CAPACITY10 command failure. "
 		       "\tNo ATA info!\n"
-		       "\tPlease run SCSI command INQUIRY firstly!\n");
+		       "\tPlease run SCSI command INQUIRY first!\n");
 		return -EPERM;
 	}
 
@@ -847,7 +847,7 @@
 	if (!ataid[pccb->target]) {
 		printf("scsi_ahci: SCSI READ CAPACITY16 command failure. "
 		       "\tNo ATA info!\n"
-		       "\tPlease run SCSI command INQUIRY firstly!\n");
+		       "\tPlease run SCSI command INQUIRY first!\n");
 		return -EPERM;
 	}
 
diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c
index 1565a9a..f65b499 100644
--- a/drivers/mtd/nand/pxa3xx_nand.c
+++ b/drivers/mtd/nand/pxa3xx_nand.c
@@ -451,7 +451,7 @@
 }
 
 /**
- * NOTE: it is a must to set ND_RUN firstly, then write
+ * NOTE: it is a must to set ND_RUN first, then write
  * command buffer, otherwise, it does not work.
  * We enable all the interrupt at the same time, and
  * let pxa3xx_nand_irq to handle all logic.
diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
index 422d3ae..f1bd15b 100644
--- a/drivers/serial/serial.c
+++ b/drivers/serial/serial.c
@@ -527,7 +527,7 @@
  *
  * Do a loopback test of the currently selected serial port. This
  * function is only useful in the context of the POST testing framwork.
- * The serial port is firstly configured into loopback mode and then
+ * The serial port is first configured into loopback mode and then
  * characters are sent through it.
  *
  * Returns 0 on success, value otherwise.