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-rw-r--r--gpxe/src/drivers/net/virtio-ring.h93
1 files changed, 93 insertions, 0 deletions
diff --git a/gpxe/src/drivers/net/virtio-ring.h b/gpxe/src/drivers/net/virtio-ring.h
new file mode 100644
index 00000000..33060b11
--- /dev/null
+++ b/gpxe/src/drivers/net/virtio-ring.h
@@ -0,0 +1,93 @@
+#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;
+};
+
+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;
+}
+
+#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))
+#endif /* _VIRTIO_RING_H_ */