1 files changed, 142 insertions, 0 deletions
diff --git a/src/include/ipxe/virtio-ring.h b/src/include/ipxe/virtio-ring.h
new file mode 100644
index 000000000..e96dd371d
--- /dev/null
+++ b/src/include/ipxe/virtio-ring.h
@@ -0,0 +1,142 @@
+#ifndef _VIRTIO_RING_H_
+# define _VIRTIO_RING_H_
+#define PAGE_SHIFT (12)
+#define PAGE_SIZE  (1<<PAGE_SHIFT)
+#define PAGE_MASK  (PAGE_SIZE-1)
+
+/* Status byte for guest to report progress, and synchronize features. */
+/* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */
+#define VIRTIO_CONFIG_S_ACKNOWLEDGE     1
+/* We have found a driver for the device. */
+#define VIRTIO_CONFIG_S_DRIVER          2
+/* Driver has used its parts of the config, and is happy */
+#define VIRTIO_CONFIG_S_DRIVER_OK       4
+/* We've given up on this device. */
+#define VIRTIO_CONFIG_S_FAILED          0x80
+
+#define MAX_QUEUE_NUM      (512)
+
+#define VRING_DESC_F_NEXT  1
+#define VRING_DESC_F_WRITE 2
+
+#define VRING_AVAIL_F_NO_INTERRUPT 1
+
+#define VRING_USED_F_NO_NOTIFY     1
+
+struct vring_desc
+{
+   u64 addr;
+   u32 len;
+   u16 flags;
+   u16 next;
+};
+
+struct vring_avail
+{
+   u16 flags;
+   u16 idx;
+   u16 ring[0];
+};
+
+struct vring_used_elem
+{
+   u32 id;
+   u32 len;
+};
+
+struct vring_used
+{
+   u16 flags;
+   u16 idx;
+   struct vring_used_elem ring[];
+};
+
+struct vring {
+   unsigned int num;
+   struct vring_desc *desc;
+   struct vring_avail *avail;
+   struct vring_used *used;
+};
+
+#define vring_size(num) \
+   (((((sizeof(struct vring_desc) * num) + \
+      (sizeof(struct vring_avail) + sizeof(u16) * num)) \
+         + PAGE_MASK) & ~PAGE_MASK) + \
+         (sizeof(struct vring_used) + sizeof(struct vring_used_elem) * num))
+
+typedef unsigned char virtio_queue_t[PAGE_MASK + vring_size(MAX_QUEUE_NUM)];
+
+struct vring_virtqueue {
+   virtio_queue_t queue;
+   struct vring vring;
+   u16 free_head;
+   u16 last_used_idx;
+   u16 vdata[MAX_QUEUE_NUM];
+   /* PCI */
+   int queue_index;
+};
+
+struct vring_list {
+  char *addr;
+  unsigned int length;
+};
+
+static inline void vring_init(struct vring *vr,
+                         unsigned int num, unsigned char *queue)
+{
+   unsigned int i;
+   unsigned long pa;
+
+        vr->num = num;
+
+   /* physical address of desc must be page aligned */
+
+   pa = virt_to_phys(queue);
+   pa = (pa + PAGE_MASK) & ~PAGE_MASK;
+   vr->desc = phys_to_virt(pa);
+
+        vr->avail = (struct vring_avail *)&vr->desc[num];
+
+   /* physical address of used must be page aligned */
+
+   pa = virt_to_phys(&vr->avail->ring[num]);
+   pa = (pa + PAGE_MASK) & ~PAGE_MASK;
+        vr->used = phys_to_virt(pa);
+
+   for (i = 0; i < num - 1; i++)
+           vr->desc[i].next = i + 1;
+   vr->desc[i].next = 0;
+}
+
+static inline void vring_enable_cb(struct vring_virtqueue *vq)
+{
+   vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
+}
+
+static inline void vring_disable_cb(struct vring_virtqueue *vq)
+{
+   vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
+}
+
+
+/*
+ * vring_more_used
+ *
+ * is there some used buffers ?
+ *
+ */
+
+static inline int vring_more_used(struct vring_virtqueue *vq)
+{
+   wmb();
+   return vq->last_used_idx != vq->vring.used->idx;
+}
+
+void vring_detach(struct vring_virtqueue *vq, unsigned int head);
+int vring_get_buf(struct vring_virtqueue *vq, unsigned int *len);
+void vring_add_buf(struct vring_virtqueue *vq, struct vring_list list[],
+                   unsigned int out, unsigned int in,
+                   int index, int num_added);
+void vring_kick(unsigned int ioaddr, struct vring_virtqueue *vq, int num_added);
+
+#endif /* _VIRTIO_RING_H_ */