iwlagn: introduce transport layer and implement rx_init

The transport layer is responsible for all the queues, DMA rings etc...
This is the beginning of the separation of all the code that is tighly
related to HW design to the aforementioned transport layer.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>

1 files changed, 155 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-trans.c b/drivers/net/wireless/iwlwifi/iwl-trans.c
new file mode 100644
index 000000000000..ccf73ff63956
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/iwl-trans.c
@@ -0,0 +1,155 @@
+/******************************************************************************
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2007 - 2011 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program 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,
+ * USA
+ *
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * Contact Information:
+ *  Intel Linux Wireless <ilw@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *  * Neither the name Intel Corporation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
+ * OWNER 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 "iwl-dev.h"
+#include "iwl-trans.h"
+
+static int iwl_trans_rx_alloc(struct iwl_priv *priv)
+{
+        struct iwl_rx_queue *rxq = &priv->rxq;
+        struct device *dev = priv->bus.dev;
+
+        memset(&priv->rxq, 0, sizeof(priv->rxq));
+
+        spin_lock_init(&rxq->lock);
+        INIT_LIST_HEAD(&rxq->rx_free);
+        INIT_LIST_HEAD(&rxq->rx_used);
+
+        if (WARN_ON(rxq->bd || rxq->rb_stts))
+                return -EINVAL;
+
+        /* Allocate the circular buffer of Read Buffer Descriptors (RBDs) */
+        /*Every descriptor is an __le32, hence its */
+        rxq->bd = dma_alloc_coherent(dev, 4 * RX_QUEUE_SIZE, &rxq->bd_dma,
+                                     GFP_KERNEL);
+        if (!rxq->bd)
+                goto err_bd;
+        memset(rxq->bd, 0, 4 * RX_QUEUE_SIZE);
+
+        /*Allocate the driver's pointer to receive buffer status */
+        rxq->rb_stts = dma_alloc_coherent(dev, sizeof(*rxq->rb_stts),
+                                          &rxq->rb_stts_dma, GFP_KERNEL);
+        if (!rxq->rb_stts)
+                goto err_rb_stts;
+        memset(rxq->rb_stts, 0, sizeof(*rxq->rb_stts));
+
+        return 0;
+
+err_rb_stts:
+        dma_free_coherent(dev, 4 * RX_QUEUE_SIZE, rxq->bd, rxq->bd_dma);
+        memset(&rxq->bd_dma, 0, sizeof(rxq->bd_dma));
+        rxq->bd = NULL;
+err_bd:
+        return -ENOMEM;
+}
+
+static int iwl_trans_rx_init(struct iwl_priv *priv)
+{
+        struct iwl_rx_queue *rxq = &priv->rxq;
+        int i, err;
+        unsigned long flags;
+
+        if (!rxq->bd) {
+                err = iwl_trans_rx_alloc(priv);
+                if (err)
+                        return err;
+        }
+
+        spin_lock_irqsave(&rxq->lock, flags);
+        INIT_LIST_HEAD(&rxq->rx_free);
+        INIT_LIST_HEAD(&rxq->rx_used);
+
+        /* Fill the rx_used queue with _all_ of the Rx buffers */
+        for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) {
+                /* In the reset function, these buffers may have been allocated
+                 * to an SKB, so we need to unmap and free potential storage */
+                if (rxq->pool[i].page != NULL) {
+                        dma_unmap_page(priv->bus.dev, rxq->pool[i].page_dma,
+                                PAGE_SIZE << priv->hw_params.rx_page_order,
+                                DMA_FROM_DEVICE);
+                        __iwl_free_pages(priv, rxq->pool[i].page);
+                        rxq->pool[i].page = NULL;
+                }
+                list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
+        }
+
+        for (i = 0; i < RX_QUEUE_SIZE; i++)
+                rxq->queue[i] = NULL;
+
+        /* Set us so that we have processed and used all buffers, but have
+         * not restocked the Rx queue with fresh buffers */
+        rxq->read = rxq->write = 0;
+        rxq->write_actual = 0;
+        rxq->free_count = 0;
+        spin_unlock_irqrestore(&rxq->lock, flags);
+
+        return 0;
+}
+
+static const struct iwl_trans_ops trans_ops = {
+        .rx_init = iwl_trans_rx_init,
+};
+
+void iwl_trans_register(struct iwl_trans *trans)
+{
+        trans->ops = &trans_ops;
+}