2 * Copyright (C) 2019 Justin Hibbits
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
17 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
18 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
19 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
20 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
21 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
22 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 #include <sys/cdefs.h>
28 #include <sys/param.h>
29 #include <sys/eventhandler.h>
30 #include <sys/malloc.h>
38 #include <machine/cpufunc.h>
41 * Manage asynchronous tokens for the OPAL abstraction layer.
43 * Only a finite number of in-flight tokens are supported by OPAL, so we must be
44 * careful managing this. The basic design uses the vmem subsystem as a general
45 * purpose allocator, with wrappers to manage expected behaviors and
48 static vmem_t *async_token_pool;
50 static void opal_handle_async_completion(void *, struct opal_msg *);
52 struct async_completion {
53 volatile uint64_t completed;
57 struct async_completion *completions;
59 /* Setup the token pool. */
61 opal_init_async_tokens(int count)
63 /* Only allow one initialization */
64 if (async_token_pool != NULL)
67 async_token_pool = vmem_create("OPAL Async", 0, count, 1, 1,
68 M_WAITOK | M_FIRSTFIT);
69 completions = malloc(count * sizeof(struct async_completion),
70 M_DEVBUF, M_WAITOK | M_ZERO);
72 EVENTHANDLER_REGISTER(OPAL_ASYNC_COMP, opal_handle_async_completion,
73 NULL, EVENTHANDLER_PRI_ANY);
79 opal_alloc_async_token(void)
83 vmem_alloc(async_token_pool, 1, M_FIRSTFIT | M_WAITOK, &token);
84 completions[token].completed = false;
90 opal_free_async_token(int token)
93 vmem_free(async_token_pool, token, 1);
97 * Wait for the operation watched by the token to complete. Return the result
98 * of the operation, error if it returns early.
101 opal_wait_completion(void *buf, uint64_t size, int token)
106 err = opal_call(OPAL_CHECK_ASYNC_COMPLETION,
107 vtophys(buf), size, token);
108 if (err == OPAL_BUSY) {
109 if (completions[token].completed) {
110 atomic_thread_fence_acq();
111 memcpy(buf, &completions[token].msg, size);
112 return (OPAL_SUCCESS);
116 } while (err == OPAL_BUSY);
121 static void opal_handle_async_completion(void *arg, struct opal_msg *msg)
125 token = msg->params[0];
126 memcpy(&completions[token].msg, msg, sizeof(*msg));
127 atomic_thread_fence_rel();
128 completions[token].completed = true;