diff --git a/drivers/ide/pci/piix.c b/drivers/ide/pci/piix.c
index 41a3612..4f69cd0 100644
--- a/drivers/ide/pci/piix.c
+++ b/drivers/ide/pci/piix.c
@@ -498,6 +498,7 @@
 		.autodma	= AUTODMA,		\
 		.enablebits	= {{0x41,0x80,0x80}, {0x43,0x80,0x80}}, \
 		.bootable	= ON_BOARD,		\
+		.pio_mask	= ATA_PIO4,		\
 		.udma_mask	= udma,			\
 	}
 
@@ -517,6 +518,7 @@
 		.enablebits	= {{0x6d,0xc0,0x80}, {0x6d,0xc0,0xc0}},
 		.bootable	= ON_BOARD,
 		.host_flags	= IDE_HFLAG_ISA_PORTS,
+		.pio_mask	= ATA_PIO4,
 	},
 
 	/*  3 */ DECLARE_PIIX_DEV("PIIX3", 0x00),	/* no udma */