[src/trunk]: src/sys/external/bsd/drm2/linux dma fence chain stubs

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/94feed6f2017
branches:  trunk
changeset: 1028350:94feed6f2017
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sun Dec 19 10:47:06 2021 +0000

description:
dma fence chain stubs

diffstat:

 sys/external/bsd/drm2/include/linux/dma-fence-chain.h |    4 +-
 sys/external/bsd/drm2/linux/files.drmkms_linux        |    3 +-
 sys/external/bsd/drm2/linux/linux_dma_fence_chain.c   |  142 ++++++++++++++++++
 3 files changed, 147 insertions(+), 2 deletions(-)

diffs (181 lines):

diff -r b7fda509b77a -r 94feed6f2017 sys/external/bsd/drm2/include/linux/dma-fence-chain.h
--- a/sys/external/bsd/drm2/include/linux/dma-fence-chain.h     Sun Dec 19 10:46:55 2021 +0000
+++ b/sys/external/bsd/drm2/include/linux/dma-fence-chain.h     Sun Dec 19 10:47:06 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: dma-fence-chain.h,v 1.2 2021/12/19 10:38:53 riastradh Exp $    */
+/*     $NetBSD: dma-fence-chain.h,v 1.3 2021/12/19 10:47:06 riastradh Exp $    */
 
 /*-
  * Copyright (c) 2020 The NetBSD Foundation, Inc.
@@ -36,6 +36,8 @@
 struct dma_fence_chain {
        struct dma_fence        base;
        uint64_t                prev_seqno;
+
+       spinlock_t              dfc_lock;
 };
 
 #define        dma_fence_chain_find_seqno      linux_dma_fence_chain_find_seqno
diff -r b7fda509b77a -r 94feed6f2017 sys/external/bsd/drm2/linux/files.drmkms_linux
--- a/sys/external/bsd/drm2/linux/files.drmkms_linux    Sun Dec 19 10:46:55 2021 +0000
+++ b/sys/external/bsd/drm2/linux/files.drmkms_linux    Sun Dec 19 10:47:06 2021 +0000
@@ -1,4 +1,4 @@
-#       $NetBSD: files.drmkms_linux,v 1.26 2021/12/19 10:46:55 riastradh Exp $
+#       $NetBSD: files.drmkms_linux,v 1.27 2021/12/19 10:47:06 riastradh Exp $
 
 define drmkms_linux: i2cexec, i2c_bitbang
 
@@ -9,6 +9,7 @@
 file   external/bsd/drm2/linux/linux_backlight.c       drmkms_linux
 file   external/bsd/drm2/linux/linux_dma_buf.c         drmkms_linux
 file   external/bsd/drm2/linux/linux_dma_fence.c       drmkms_linux
+file   external/bsd/drm2/linux/linux_dma_fence_chain.c drmkms_linux
 file   external/bsd/drm2/linux/linux_dma_resv.c        drmkms_linux
 file   external/bsd/drm2/linux/linux_dmi.c             drmkms_linux
 file   external/bsd/drm2/linux/linux_i2c.c             drmkms_linux
diff -r b7fda509b77a -r 94feed6f2017 sys/external/bsd/drm2/linux/linux_dma_fence_chain.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/external/bsd/drm2/linux/linux_dma_fence_chain.c       Sun Dec 19 10:47:06 2021 +0000
@@ -0,0 +1,142 @@
+/*     $NetBSD: linux_dma_fence_chain.c,v 1.1 2021/12/19 10:47:06 riastradh Exp $      */
+
+/*-
+ * Copyright (c) 2020 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Taylor R. Campbell.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 THE FOUNDATION 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.
+ */
+
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: linux_dma_fence_chain.c,v 1.1 2021/12/19 10:47:06 riastradh Exp $");
+
+#include <sys/types.h>
+
+#include <linux/dma-fence.h>
+#include <linux/dma-fence-chain.h>
+#include <linux/spinlock.h>
+
+static const struct dma_fence_ops dma_fence_chain_ops;
+
+/*
+ * dma_fence_chain_init(chain, prev, fence, seqno)
+ *
+ *     Initialize a new fence chain, and either start 
+ */
+void
+dma_fence_chain_init(struct dma_fence_chain *chain, struct dma_fence *prev,
+    struct dma_fence *fence, uint64_t seqno)
+{
+       uint64_t context = -1;  /* XXX */
+
+       chain->prev_seqno = 0;
+       spin_lock_init(&chain->dfc_lock);
+
+       /* XXX we don't use these yet */
+       dma_fence_put(prev);
+       dma_fence_put(fence);
+
+       dma_fence_init(&chain->base, &dma_fence_chain_ops, &chain->dfc_lock,
+           context, seqno);
+}
+
+static void
+dma_fence_chain_release(struct dma_fence *fence)
+{
+       struct dma_fence_chain *chain = to_dma_fence_chain(fence);
+
+       KASSERT(chain);
+
+       spin_lock_destroy(&chain->dfc_lock);
+       dma_fence_free(&chain->base);
+}
+
+static const struct dma_fence_ops dma_fence_chain_ops = {
+       .release = dma_fence_chain_release,
+};
+
+/*
+ * to_dma_fence_chain(fence)
+ *
+ *     If fence is nonnull and in a chain, return the chain.
+ *     Otherwise return NULL.
+ */
+struct dma_fence_chain *
+to_dma_fence_chain(struct dma_fence *fence)
+{
+
+       if (fence == NULL || fence->ops != &dma_fence_chain_ops)
+               return NULL;
+       return container_of(fence, struct dma_fence_chain, base);
+}
+
+/*
+ * dma_fence_chain_walk(fence)
+ *
+ *     Return the next fence in the chain, or NULL if end of chain,
+ *     after releasing any fences that have already been signalled.
+ */
+struct dma_fence *
+dma_fence_chain_walk(struct dma_fence *fence)
+{
+
+       /* XXX */
+       return NULL;
+}
+
+/*
+ * dma_fence_chain_find_seqno(&fence, seqno)
+ *
+ *     If seqno is zero, do nothing and succeed.
+ *
+ *     Otherwise, if fence is not on a chain or if its sequence
+ *     number has not yet reached seqno, fail with EINVAL.
+ *
+ *     Otherwise, set fence to the first fence in the chain which
+ *     will signal this sequence number.
+ */
+int
+dma_fence_chain_find_seqno(struct dma_fence **fencep, uint64_t seqno)
+{
+       struct dma_fence_chain *chain;
+
+       if (seqno == 0)
+               return 0;
+
+       chain = to_dma_fence_chain(*fencep);
+       if (chain == NULL || chain->base.seqno < seqno)
+               return -EINVAL;
+
+       dma_fence_chain_for_each(*fencep, &chain->base) {
+               if ((*fencep)->context != chain->base.context ||
+                   to_dma_fence_chain(*fencep)->prev_seqno < seqno)
+                       break;
+       }
+
+       /* Release reference acquired by dma_fence_chain_for_each.  */
+       dma_fence_put(&chain->base);
+
+       return 0;
+}