drivers/net/wireless/iwlwifi/iwl-trans.c

   1 /******************************************************************************
   2  *
   3  * This file is provided under a dual BSD/GPLv2 license.  When using or
   4  * redistributing this file, you may do so under either license.
   5  *
   6  * GPL LICENSE SUMMARY
   7  *
   8  * Copyright(c) 2007 - 2011 Intel Corporation. All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of version 2 of the GNU General Public License as
  12  * published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
  22  * USA
  23  *
  24  * The full GNU General Public License is included in this distribution
  25  * in the file called LICENSE.GPL.
  26  *
  27  * Contact Information:
  28  *  Intel Linux Wireless <ilw@linux.intel.com>
  29  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  30  *
  31  * BSD LICENSE
  32  *
  33  * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved.
  34  * All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
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  39  *
  40  *  * Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  *  * Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in
  44  *    the documentation and/or other materials provided with the
  45  *    distribution.
  46  *  * Neither the name Intel Corporation nor the names of its
  47  *    contributors may be used to endorse or promote products derived
  48  *    from this software without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  54  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  55  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  56  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  57  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  58  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  59  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  60  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  *
  62  *****************************************************************************/
  63 #include "iwl-dev.h"
  64 #include "iwl-trans.h"
  65
  66 static int iwl_trans_rx_alloc(struct iwl_priv *priv)
  67 {
  68         struct iwl_rx_queue *rxq = &priv->rxq;
  69         struct device *dev = priv->bus.dev;
  70
  71         memset(&priv->rxq, 0, sizeof(priv->rxq));
  72
  73         spin_lock_init(&rxq->lock);
  74         INIT_LIST_HEAD(&rxq->rx_free);
  75         INIT_LIST_HEAD(&rxq->rx_used);
  76
  77         if (WARN_ON(rxq->bd || rxq->rb_stts))
  78                 return -EINVAL;
  79
  80         /* Allocate the circular buffer of Read Buffer Descriptors (RBDs) */
  81         rxq->bd = dma_alloc_coherent(dev, sizeof(__le32) * RX_QUEUE_SIZE,
  82                                      &rxq->bd_dma, GFP_KERNEL);
  83         if (!rxq->bd)
  84                 goto err_bd;
  85         memset(rxq->bd, 0, sizeof(__le32) * RX_QUEUE_SIZE);
  86
  87         /*Allocate the driver's pointer to receive buffer status */
  88         rxq->rb_stts = dma_alloc_coherent(dev, sizeof(*rxq->rb_stts),
  89                                           &rxq->rb_stts_dma, GFP_KERNEL);
  90         if (!rxq->rb_stts)
  91                 goto err_rb_stts;
  92         memset(rxq->rb_stts, 0, sizeof(*rxq->rb_stts));
  93
  94         return 0;
  95
  96 err_rb_stts:
  97         dma_free_coherent(dev, sizeof(__le32) * RX_QUEUE_SIZE,
  98                         rxq->bd, rxq->bd_dma);
  99         memset(&rxq->bd_dma, 0, sizeof(rxq->bd_dma));
 100         rxq->bd = NULL;
 101 err_bd:
 102         return -ENOMEM;
 103 }
 104
 105 static void iwl_trans_rxq_free_rx_bufs(struct iwl_priv *priv)
 106 {
 107         struct iwl_rx_queue *rxq = &priv->rxq;
 108         int i;
 109
 110         /* Fill the rx_used queue with _all_ of the Rx buffers */
 111         for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) {
 112                 /* In the reset function, these buffers may have been allocated
 113                  * to an SKB, so we need to unmap and free potential storage */
 114                 if (rxq->pool[i].page != NULL) {
 115                         dma_unmap_page(priv->bus.dev, rxq->pool[i].page_dma,
 116                                 PAGE_SIZE << priv->hw_params.rx_page_order,
 117                                 DMA_FROM_DEVICE);
 118                         __iwl_free_pages(priv, rxq->pool[i].page);
 119                         rxq->pool[i].page = NULL;
 120                 }
 121                 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
 122         }
 123 }
 124
 125 static int iwl_trans_rx_init(struct iwl_priv *priv)
 126 {
 127         struct iwl_rx_queue *rxq = &priv->rxq;
 128         int i, err;
 129         unsigned long flags;
 130
 131         if (!rxq->bd) {
 132                 err = iwl_trans_rx_alloc(priv);
 133                 if (err)
 134                         return err;
 135         }
 136
 137         spin_lock_irqsave(&rxq->lock, flags);
 138         INIT_LIST_HEAD(&rxq->rx_free);
 139         INIT_LIST_HEAD(&rxq->rx_used);
 140
 141         iwl_trans_rxq_free_rx_bufs(priv);
 142
 143         for (i = 0; i < RX_QUEUE_SIZE; i++)
 144                 rxq->queue[i] = NULL;
 145
 146         /* Set us so that we have processed and used all buffers, but have
 147          * not restocked the Rx queue with fresh buffers */
 148         rxq->read = rxq->write = 0;
 149         rxq->write_actual = 0;
 150         rxq->free_count = 0;
 151         spin_unlock_irqrestore(&rxq->lock, flags);
 152
 153         return 0;
 154 }
 155
 156 static void iwl_trans_rx_free(struct iwl_priv *priv)
 157 {
 158         struct iwl_rx_queue *rxq = &priv->rxq;
 159         unsigned long flags;
 160
 161         /*if rxq->bd is NULL, it means that nothing has been allocated,
 162          * exit now */
 163         if (!rxq->bd) {
 164                 IWL_DEBUG_INFO(priv, "Free NULL rx context\n");
 165                 return;
 166         }
 167
 168         spin_lock_irqsave(&rxq->lock, flags);
 169         iwl_trans_rxq_free_rx_bufs(priv);
 170         spin_unlock_irqrestore(&rxq->lock, flags);
 171
 172         dma_free_coherent(priv->bus.dev, sizeof(__le32) * RX_QUEUE_SIZE,
 173                           rxq->bd, rxq->bd_dma);
 174         memset(&rxq->bd_dma, 0, sizeof(rxq->bd_dma));
 175         rxq->bd = NULL;
 176
 177         if (rxq->rb_stts)
 178                 dma_free_coherent(priv->bus.dev,
 179                                   sizeof(struct iwl_rb_status),
 180                                   rxq->rb_stts, rxq->rb_stts_dma);
 181         else
 182                 IWL_DEBUG_INFO(priv, "Free rxq->rb_stts which is NULL\n");
 183         memset(&rxq->rb_stts_dma, 0, sizeof(rxq->rb_stts_dma));
 184         rxq->rb_stts = NULL;
 185 }
 186
 187 static const struct iwl_trans_ops trans_ops = {
 188         .rx_init = iwl_trans_rx_init,
 189         .rx_free = iwl_trans_rx_free,
 190 };
 191
 192 void iwl_trans_register(struct iwl_trans *trans)
 193 {
 194         trans->ops = &trans_ops;
 195 }