src/gallium/drivers/vc4/vc4_fence.c

   1 /*
   2  * Copyright © 2014 Broadcom
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  */
  23
  24 /** @file vc4_fence.c
  25  *
  26  * Seqno-based fence management.
  27  *
  28  * We have two mechanisms for waiting in our kernel API: You can wait on a BO
  29  * to have all rendering to from any process to be completed, or wait on a
  30  * seqno for that particular seqno to be passed.  The fence API we're
  31  * implementing is based on waiting for all rendering in the context to have
  32  * completed (with no reference to what other processes might be doing with
  33  * the same BOs), so we can just use the seqno of the last rendering we'd
  34  * fired off as our fence marker.
  35  */
  36
  37 #include "util/u_inlines.h"
  38
  39 #include "vc4_screen.h"
  40 #include "vc4_bufmgr.h"
  41
  42 struct vc4_fence {
  43         struct pipe_reference reference;
  44         uint64_t seqno;
  45 };
  46
  47 static void
  48 vc4_fence_reference(struct pipe_screen *pscreen,
  49                     struct pipe_fence_handle **pp,
  50                     struct pipe_fence_handle *pf)
  51 {
  52         struct vc4_fence **p = (struct vc4_fence **)pp;
  53         struct vc4_fence *f = (struct vc4_fence *)pf;
  54         struct vc4_fence *old = *p;
  55
  56         if (pipe_reference(&(*p)->reference, &f->reference)) {
  57                 free(old);
  58         }
  59         *p = f;
  60 }
  61
  62 static boolean
  63 vc4_fence_finish(struct pipe_screen *pscreen,
  64                  struct pipe_fence_handle *pf,
  65                  uint64_t timeout_ns)
  66 {
  67         struct vc4_screen *screen = vc4_screen(pscreen);
  68         struct vc4_fence *f = (struct vc4_fence *)pf;
  69
  70         return vc4_wait_seqno(screen, f->seqno, timeout_ns);
  71 }
  72
  73 struct vc4_fence *
  74 vc4_fence_create(struct vc4_screen *screen, uint64_t seqno)
  75 {
  76         struct vc4_fence *f = calloc(1, sizeof(*f));
  77
  78         if (!f)
  79                 return NULL;
  80
  81         pipe_reference_init(&f->reference, 1);
  82         f->seqno = seqno;
  83
  84         return f;
  85 }
  86
  87 void
  88 vc4_fence_init(struct vc4_screen *screen)
  89 {
  90         screen->base.fence_reference = vc4_fence_reference;
  91         screen->base.fence_finish = vc4_fence_finish;
  92 }