1 files changed, 103 insertions, 0 deletions
diff --git a/gcell/src/lib/runtime/spu/gc_spu_jd_queue.c b/gcell/src/lib/runtime/spu/gc_spu_jd_queue.c
new file mode 100644
index 000000000..ba4a1b9d2
--- /dev/null
+++ b/gcell/src/lib/runtime/spu/gc_spu_jd_queue.c
@@ -0,0 +1,103 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "gc_jd_queue.h"
+#include "mutex_lock.h"
+#include "mutex_unlock.h"
+
+extern int gc_sys_tag;
+
+bool
+gc_jd_queue_dequeue(gc_eaddr_t q, gc_eaddr_t *item_ea, gc_job_desc_t *item)
+{
+  gc_jd_queue_t	local_q;
+
+  // Before aquiring the lock, see if it's possible that there's
+  // something in the queue.  Checking in this way makes it easier
+  // for the PPE to insert things, since we're not contending for
+  // the lock unless there is something in the queue.
+
+  // copy in the queue structure
+  mfc_get(&local_q, q, sizeof(gc_jd_queue_t), gc_sys_tag, 0, 0);
+  mfc_write_tag_mask(1 << gc_sys_tag);	// the tag we're interested in
+  mfc_read_tag_status_all();		// wait for DMA to complete
+
+  if (local_q.head == 0){		// empty
+    return false;
+  }
+
+  // When we peeked, head was non-zero.  Now grab the
+  // lock and do it for real.
+
+  _mutex_lock(q + offsetof(gc_jd_queue_t, mutex));
+
+  // copy in the queue structure
+  mfc_get(&local_q, q, sizeof(gc_jd_queue_t), gc_sys_tag, 0, 0);
+  mfc_write_tag_mask(1 << gc_sys_tag);	// the tag we're interested in
+  mfc_read_tag_status_all();		// wait for DMA to complete
+
+  if (local_q.head == 0){		// empty
+    _mutex_unlock(q + offsetof(gc_jd_queue_t, mutex));
+    return false;
+  }
+
+  // copy in job descriptor at head of queue
+  *item_ea = local_q.head;
+  mfc_get(item, local_q.head, sizeof(gc_job_desc_t), gc_sys_tag, 0, 0);
+  mfc_write_tag_mask(1 << gc_sys_tag);	// the tag we're interested in
+  mfc_read_tag_status_all();		// wait for DMA to complete
+
+  local_q.head = item->sys.next;
+  item->sys.next = 0;
+  if (local_q.head == 0)		// now empty?
+    local_q.tail = 0;
+
+
+  // copy the queue structure back out
+  mfc_put(&local_q, q, sizeof(gc_jd_queue_t), gc_sys_tag, 0, 0);
+  mfc_write_tag_mask(1 << gc_sys_tag);	// the tag we're interested in
+  mfc_read_tag_status_all();		// wait for DMA to complete
+
+  // Q: FIXME do we need to order stores in EA or can we just clear the
+  // local copy of the mutex above and blast it out, removing the need
+  // for this explicit unlock?
+  //
+  // A: Manual says it's better to use an atomic op rather than
+  // a normal DMA, and that a putlluc is better than a putllc if
+  // you can use it.
+
+  _mutex_unlock(q + offsetof(gc_jd_queue_t, mutex));
+  return true;
+}
+
+
+void
+gc_jd_queue_getllar(gc_eaddr_t q)
+{
+  // get reservation that includes the tail of the queue
+  gc_eaddr_t	tail = q + offsetof(gc_jd_queue_t, tail);
+    
+  char _tmp[256];
+  char *buf = (char *) ALIGN(_tmp, 128);	// get cache-aligned buffer
+
+  mfc_getllar(buf, ALIGN128_EA(tail), 0, 0);
+  spu_readch(MFC_RdAtomicStat);
+}