initial commit, FreeRTOS_BSP_1.0.0_iMX7D

1 files changed, 165 insertions, 0 deletions

diff --git a/middleware/multicore/open-amp/virtio/virtio_ring.h b/middleware/multicore/open-amp/virtio/virtio_ring.h
new file mode 100644
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+++ b/middleware/multicore/open-amp/virtio/virtio_ring.h
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+/*-
+ * Copyright Rusty Russell IBM Corporation 2007.
+ *
+ * This header is BSD licensed so anyone can use the definitions to implement
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef VIRTIO_RING_H
+#define	VIRTIO_RING_H
+
+/* This marks a buffer as continuing via the next field. */
+#define VRING_DESC_F_NEXT       1
+/* This marks a buffer as write-only (otherwise read-only). */
+#define VRING_DESC_F_WRITE      2
+/* This means the buffer contains a list of buffer descriptors. */
+#define VRING_DESC_F_INDIRECT	4   /*not used?*/
+
+/* The Host uses this in used->flags to advise the Guest: don't kick me
+ * when you add a buffer.  It's unreliable, so it's simply an
+ * optimization.  Guest will still kick if it's out of buffers. */
+#define VRING_USED_F_NO_NOTIFY  1
+/* The Guest uses this in avail->flags to advise the Host: don't
+ * interrupt me when you consume a buffer.  It's unreliable, so it's
+ * simply an optimization.  */
+#define VRING_AVAIL_F_NO_INTERRUPT      1
+
+/* VirtIO ring descriptors: 16 bytes.
+ * These can chain together via "next". */
+struct vring_desc {
+        /* Address (guest-physical). */
+        uint64_t addr;
+        /* Length. */
+        uint32_t len;
+        /* The flags as indicated above. */
+        uint16_t flags;
+        /* We chain unused descriptors via this, too. */
+        uint16_t next;
+};
+
+struct vring_avail {
+        uint16_t flags;
+        uint16_t idx;
+        uint16_t ring[0];
+};
+
+/* uint32_t is used here for ids for padding reasons. */
+struct vring_used_elem {
+        /* Index of start of used descriptor chain. */
+        uint32_t id;
+        /* Total length of the descriptor chain which was written to. */
+        uint32_t len;
+};
+
+struct vring_used {
+        uint16_t flags;
+        uint16_t idx;
+        struct vring_used_elem ring[0];
+};
+
+struct vring {
+	unsigned int num;
+
+	struct vring_desc *desc;
+	struct vring_avail *avail;
+	struct vring_used *used;
+};
+
+/* The standard layout for the ring is a continuous chunk of memory which
+ * looks like this.  We assume num is a power of 2.
+ *
+ * struct vring {
+ *      // The actual descriptors (16 bytes each)
+ *      struct vring_desc desc[num];
+ *
+ *      // A ring of available descriptor heads with free-running index.
+ *      __u16 avail_flags;
+ *      __u16 avail_idx;
+ *      __u16 available[num];
+ *      __u16 used_event_idx;
+ *
+ *      // Padding to the next align boundary.
+ *      char pad[];
+ *
+ *      // A ring of used descriptor heads with free-running index.
+ *      __u16 used_flags;
+ *      __u16 used_idx;
+ *      struct vring_used_elem used[num];
+ *      __u16 avail_event_idx;
+ * };
+ *
+ * NOTE: for VirtIO PCI, align is 4096.
+ */
+
+/*
+ * We publish the used event index at the end of the available ring, and vice
+ * versa. They are at the end for backwards compatibility.
+ */
+#define vring_used_event(vr)	((vr)->avail->ring[(vr)->num])
+#define vring_avail_event(vr)	(*(uint16_t *)&(vr)->used->ring[(vr)->num])
+
+static inline int
+vring_size(unsigned int num, unsigned long align)
+{
+	int size;
+
+	size = num * sizeof(struct vring_desc);
+	size += sizeof(struct vring_avail) + (num * sizeof(uint16_t)) +
+	    sizeof(uint16_t);
+	size = (size + align - 1) & ~(align - 1);
+	size += sizeof(struct vring_used) +
+	    (num * sizeof(struct vring_used_elem)) + sizeof(uint16_t);
+	return (size);
+}
+
+static inline void
+vring_init(struct vring *vr, unsigned int num, uint8_t *p,
+    unsigned long align)
+{
+        vr->num = num;
+        vr->desc = (struct vring_desc *) p;
+        vr->avail = (struct vring_avail *) (p +
+	    num * sizeof(struct vring_desc));
+        vr->used = (void *)
+	    (((unsigned long) &vr->avail->ring[num] + align-1) & ~(align-1));
+}
+
+/*
+ * The following is used with VIRTIO_RING_F_EVENT_IDX.
+ *
+ * Assuming a given event_idx value from the other size, if we have
+ * just incremented index from old to new_idx, should we trigger an
+ * event?
+ */
+static inline int
+vring_need_event(uint16_t event_idx, uint16_t new_idx, uint16_t old)
+{
+
+	return (uint16_t)(new_idx - event_idx - 1) < (uint16_t)(new_idx - old);
+}
+#endif /* VIRTIO_RING_H */