--- /dev/null
+#ifndef _VIRTIO_PCI_H
+#define _VIRTIO_PCI_H
+
+#include "ioport.h" // inl
+
+/* A 32-bit r/o bitmask of the features supported by the host */
+#define VIRTIO_PCI_HOST_FEATURES 0
+
+/* A 32-bit r/w bitmask of features activated by the guest */
+#define VIRTIO_PCI_GUEST_FEATURES 4
+
+/* A 32-bit r/w PFN for the currently selected queue */
+#define VIRTIO_PCI_QUEUE_PFN 8
+
+/* A 16-bit r/o queue size for the currently selected queue */
+#define VIRTIO_PCI_QUEUE_NUM 12
+
+/* A 16-bit r/w queue selector */
+#define VIRTIO_PCI_QUEUE_SEL 14
+
+/* A 16-bit r/w queue notifier */
+#define VIRTIO_PCI_QUEUE_NOTIFY 16
+
+/* An 8-bit device status register. */
+#define VIRTIO_PCI_STATUS 18
+
+/* An 8-bit r/o interrupt status register. Reading the value will return the
+ * current contents of the ISR and will also clear it. This is effectively
+ * a read-and-acknowledge. */
+#define VIRTIO_PCI_ISR 19
+
+/* The bit of the ISR which indicates a device configuration change. */
+#define VIRTIO_PCI_ISR_CONFIG 0x2
+
+/* The remaining space is defined by each driver as the per-driver
+ * configuration space */
+#define VIRTIO_PCI_CONFIG 20
+
+/* Virtio ABI version, this must match exactly */
+#define VIRTIO_PCI_ABI_VERSION 0
+
+static inline u32 vp_get_features(unsigned int ioaddr)
+{
+ return inl(ioaddr + VIRTIO_PCI_HOST_FEATURES);
+}
+
+static inline void vp_set_features(unsigned int ioaddr, u32 features)
+{
+ outl(features, ioaddr + VIRTIO_PCI_GUEST_FEATURES);
+}
+
+static inline void vp_get(unsigned int ioaddr, unsigned offset,
+ void *buf, unsigned len)
+{
+ u8 *ptr = buf;
+ unsigned i;
+
+ for (i = 0; i < len; i++)
+ ptr[i] = inb(ioaddr + VIRTIO_PCI_CONFIG + offset + i);
+}
+
+static inline u8 vp_get_status(unsigned int ioaddr)
+{
+ return inb(ioaddr + VIRTIO_PCI_STATUS);
+}
+
+static inline void vp_set_status(unsigned int ioaddr, u8 status)
+{
+ if (status == 0) /* reset */
+ return;
+ outb(status, ioaddr + VIRTIO_PCI_STATUS);
+}
+
+static inline u8 vp_get_isr(unsigned int ioaddr)
+{
+ return inb(ioaddr + VIRTIO_PCI_ISR);
+}
+
+static inline void vp_reset(unsigned int ioaddr)
+{
+ outb(0, ioaddr + VIRTIO_PCI_STATUS);
+ (void)inb(ioaddr + VIRTIO_PCI_ISR);
+}
+
+static inline void vp_notify(unsigned int ioaddr, int queue_index)
+{
+ outw(queue_index, ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
+}
+
+static inline void vp_del_vq(unsigned int ioaddr, int queue_index)
+{
+ /* select the queue */
+
+ outw(queue_index, ioaddr + VIRTIO_PCI_QUEUE_SEL);
+
+ /* deactivate the queue */
+
+ outl(0, ioaddr + VIRTIO_PCI_QUEUE_PFN);
+}
+
+struct vring_virtqueue;
+int vp_find_vq(unsigned int ioaddr, int queue_index,
+ struct vring_virtqueue *vq);
+#endif /* _VIRTIO_PCI_H_ */
