added via accelerant, a copy of skeleton driver yet.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@13582 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/accelerants/via/EngineManagement.c

@@ -0,0 +1,70 @@
+/*
+	Copyright 1999, Be Incorporated.   All Rights Reserved.
+	This file may be used under the terms of the Be Sample Code License.
+
+	other authors:
+	Mark Watson
+	Rudolf Cornelissen 3/2004
+*/
+
+#define MODULE_BIT 0x10000000
+
+#include "acc_std.h"
+
+
+static engine_token eng_engine_token = { 1, B_2D_ACCELERATION, NULL };
+
+uint32 ACCELERANT_ENGINE_COUNT(void)
+{
+	/* we have one acceleration engine */
+	return 1;
+}
+
+status_t ACQUIRE_ENGINE(uint32 capabilities, uint32 max_wait, sync_token *st, engine_token **et)
+{
+	/* acquire the shared benaphore */
+	AQUIRE_BEN(si->engine.lock)
+	/* sync if required */
+	if (st) SYNC_TO_TOKEN(st);
+
+	/* return an engine token */
+	*et = &eng_engine_token;
+	return B_OK;
+}
+
+status_t RELEASE_ENGINE(engine_token *et, sync_token *st)
+{
+	/* update the sync token, if any */
+	if (st) GET_SYNC_TOKEN(et,st);
+
+	/* release the shared benaphore */
+	RELEASE_BEN(si->engine.lock)
+	return B_OK;
+}
+
+void WAIT_ENGINE_IDLE(void)
+{
+	/*wait for the engine to be totally idle*/
+	eng_acc_wait_idle();
+}
+
+status_t GET_SYNC_TOKEN(engine_token *et, sync_token *st)
+{
+	/* engine count will always be zero: we don't support syncing to token (yet) */
+	st->engine_id = et->engine_id;
+	st->counter = si->engine.count;
+	return B_OK;
+}
+
+status_t SYNC_TO_TOKEN(sync_token *st)
+{
+	/* wait until the engine is totally idle: we don't support syncing to token (yet) */
+	/* note:
+	 * AFAIK in order to be able to setup sync_to_token, we'd need a circular fifo
+	 * buffer in (main) memory instead of directly programming the GPU fifo so we
+	 * can tell (via a hardware maintained pointer into this circular fifo) where
+	 * the acc engine is with executing commands! */
+	WAIT_ENGINE_IDLE();
+
+	return B_OK;
+}