iwlwifi: Add TFD library operations

The TFD structures for 3945 and agn HWs are fundamentally different. We thus
need to define operations for attaching and freeing them. This will allow us
to share a fair amount of code (cmd and tx queue related) between both
drivers.

Signed-off-by: Samuel Ortiz <samuel.ortiz@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-3945.c

@@ -318,7 +318,7 @@ static void iwl3945_tx_queue_reclaim(struct iwl_priv *priv,
 		tx_info = &txq->txb[txq->q.read_ptr];
 		ieee80211_tx_status_irqsafe(priv->hw, tx_info->skb[0]);
 		tx_info->skb[0] = NULL;
-		iwl3945_hw_txq_free_tfd(priv, txq);
+		priv->cfg->ops->lib->txq_free_tfd(priv, txq);
 	}
 
 	if (iwl_queue_space(q) > q->low_mark && (txq_id >= 0) &&
@@ -724,15 +724,21 @@ static void iwl3945_rx_reply_rx(struct iwl_priv *priv,
 	iwl3945_pass_packet_to_mac80211(priv, rxb, &rx_status);
 }
 
-int iwl3945_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv, void *ptr,
-				 dma_addr_t addr, u16 len)
+int iwl3945_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv,
+				     struct iwl_tx_queue *txq,
+				     dma_addr_t addr, u16 len, u8 reset, u8 pad)
 {
 	int count;
-	u32 pad;
-	struct iwl3945_tfd *tfd = (struct iwl3945_tfd *)ptr;
+	struct iwl_queue *q;
+	struct iwl3945_tfd *tfd;
+
+	q = &txq->q;
+	tfd = &txq->tfds39[q->write_ptr];
+
+	if (reset)
+		memset(tfd, 0, sizeof(*tfd));
 
 	count = TFD_CTL_COUNT_GET(le32_to_cpu(tfd->control_flags));
-	pad = TFD_CTL_PAD_GET(le32_to_cpu(tfd->control_flags));
 
 	if ((count >= NUM_TFD_CHUNKS) || (count < 0)) {
 		IWL_ERR(priv, "Error can not send more than %d chunks\n",
@@ -756,7 +762,7 @@ int iwl3945_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv, void *ptr,
  *
  * Does NOT advance any indexes
  */
-int iwl3945_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq)
+void iwl3945_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq)
 {
 	struct iwl3945_tfd *tfd_tmp = (struct iwl3945_tfd *)&txq->tfds39[0];
 	struct iwl3945_tfd *tfd = &tfd_tmp[txq->q.read_ptr];
@@ -767,14 +773,14 @@ int iwl3945_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq)
 	/* classify bd */
 	if (txq->q.id == IWL_CMD_QUEUE_NUM)
 		/* nothing to cleanup after for host commands */
-		return 0;
+		return;
 
 	/* sanity check */
 	counter = TFD_CTL_COUNT_GET(le32_to_cpu(tfd->control_flags));
 	if (counter > NUM_TFD_CHUNKS) {
 		IWL_ERR(priv, "Too many chunks: %i\n", counter);
 		/* @todo issue fatal error, it is quite serious situation */
-		return 0;
+		return;
 	}
 
 	/* unmap chunks if any */
@@ -791,7 +797,7 @@ int iwl3945_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq)
 			}
 		}
 	}
-	return 0;
+	return ;
 }
 
 u8 iwl3945_hw_find_station(struct iwl_priv *priv, const u8 *addr)
@@ -2697,6 +2703,8 @@ static int iwl3945_load_bsm(struct iwl_priv *priv)
 }
 
 static struct iwl_lib_ops iwl3945_lib = {
+	.txq_attach_buf_to_tfd = iwl3945_hw_txq_attach_buf_to_tfd,
+	.txq_free_tfd = iwl3945_hw_txq_free_tfd,
 	.load_ucode = iwl3945_load_bsm,
 	.apm_ops = {
 		.init = iwl3945_apm_init,

drivers/net/wireless/iwlwifi/iwl-3945.h

@@ -260,9 +260,12 @@ extern int iwl3945_hw_nic_stop_master(struct iwl_priv *priv);
 extern void iwl3945_hw_txq_ctx_free(struct iwl_priv *priv);
 extern void iwl3945_hw_txq_ctx_stop(struct iwl_priv *priv);
 extern int iwl3945_hw_nic_reset(struct iwl_priv *priv);
-extern int iwl3945_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv, void *tfd,
-					dma_addr_t addr, u16 len);
-extern int iwl3945_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq);
+extern int iwl3945_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv,
+					    struct iwl_tx_queue *txq,
+					    dma_addr_t addr, u16 len,
+					    u8 reset, u8 pad);
+extern void iwl3945_hw_txq_free_tfd(struct iwl_priv *priv,
+				    struct iwl_tx_queue *txq);
 extern int iwl3945_hw_get_temperature(struct iwl_priv *priv);
 extern int iwl3945_hw_tx_queue_init(struct iwl_priv *priv,
 				struct iwl_tx_queue *txq);

drivers/net/wireless/iwlwifi/iwl-4965.c

@@ -2295,6 +2295,8 @@ static struct iwl_lib_ops iwl4965_lib = {
 	.txq_set_sched = iwl4965_txq_set_sched,
 	.txq_agg_enable = iwl4965_txq_agg_enable,
 	.txq_agg_disable = iwl4965_txq_agg_disable,
+	.txq_attach_buf_to_tfd = iwl_hw_txq_attach_buf_to_tfd,
+	.txq_free_tfd = iwl_hw_txq_free_tfd,
 	.rx_handler_setup = iwl4965_rx_handler_setup,
 	.setup_deferred_work = iwl4965_setup_deferred_work,
 	.cancel_deferred_work = iwl4965_cancel_deferred_work,

drivers/net/wireless/iwlwifi/iwl-5000.c

@@ -1492,6 +1492,8 @@ static struct iwl_lib_ops iwl5000_lib = {
 	.txq_set_sched = iwl5000_txq_set_sched,
 	.txq_agg_enable = iwl5000_txq_agg_enable,
 	.txq_agg_disable = iwl5000_txq_agg_disable,
+	.txq_attach_buf_to_tfd = iwl_hw_txq_attach_buf_to_tfd,
+	.txq_free_tfd = iwl_hw_txq_free_tfd,
 	.rx_handler_setup = iwl5000_rx_handler_setup,
 	.setup_deferred_work = iwl5000_setup_deferred_work,
 	.is_valid_rtc_data_addr = iwl5000_hw_valid_rtc_data_addr,

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

@@ -471,6 +471,126 @@ static int iwl_send_beacon_cmd(struct iwl_priv *priv)
 	return rc;
 }
 
+static inline dma_addr_t iwl_tfd_tb_get_addr(struct iwl_tfd *tfd, u8 idx)
+{
+	struct iwl_tfd_tb *tb = &tfd->tbs[idx];
+
+	dma_addr_t addr = get_unaligned_le32(&tb->lo);
+	if (sizeof(dma_addr_t) > sizeof(u32))
+		addr |=
+		((dma_addr_t)(le16_to_cpu(tb->hi_n_len) & 0xF) << 16) << 16;
+
+	return addr;
+}
+
+static inline u16 iwl_tfd_tb_get_len(struct iwl_tfd *tfd, u8 idx)
+{
+	struct iwl_tfd_tb *tb = &tfd->tbs[idx];
+
+	return le16_to_cpu(tb->hi_n_len) >> 4;
+}
+
+static inline void iwl_tfd_set_tb(struct iwl_tfd *tfd, u8 idx,
+				  dma_addr_t addr, u16 len)
+{
+	struct iwl_tfd_tb *tb = &tfd->tbs[idx];
+	u16 hi_n_len = len << 4;
+
+	put_unaligned_le32(addr, &tb->lo);
+	if (sizeof(dma_addr_t) > sizeof(u32))
+		hi_n_len |= ((addr >> 16) >> 16) & 0xF;
+
+	tb->hi_n_len = cpu_to_le16(hi_n_len);
+
+	tfd->num_tbs = idx + 1;
+}
+
+static inline u8 iwl_tfd_get_num_tbs(struct iwl_tfd *tfd)
+{
+	return tfd->num_tbs & 0x1f;
+}
+
+/**
+ * iwl_hw_txq_free_tfd - Free all chunks referenced by TFD [txq->q.read_ptr]
+ * @priv - driver private data
+ * @txq - tx queue
+ *
+ * Does NOT advance any TFD circular buffer read/write indexes
+ * Does NOT free the TFD itself (which is within circular buffer)
+ */
+void iwl_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq)
+{
+	struct iwl_tfd *tfd_tmp = (struct iwl_tfd *)&txq->tfds[0];
+	struct iwl_tfd *tfd;
+	struct pci_dev *dev = priv->pci_dev;
+	int index = txq->q.read_ptr;
+	int i;
+	int num_tbs;
+
+	tfd = &tfd_tmp[index];
+
+	/* Sanity check on number of chunks */
+	num_tbs = iwl_tfd_get_num_tbs(tfd);
+
+	if (num_tbs >= IWL_NUM_OF_TBS) {
+		IWL_ERR(priv, "Too many chunks: %i\n", num_tbs);
+		/* @todo issue fatal error, it is quite serious situation */
+		return;
+	}
+
+	/* Unmap tx_cmd */
+	if (num_tbs)
+		pci_unmap_single(dev,
+				pci_unmap_addr(&txq->cmd[index]->meta, mapping),
+				pci_unmap_len(&txq->cmd[index]->meta, len),
+				PCI_DMA_TODEVICE);
+
+	/* Unmap chunks, if any. */
+	for (i = 1; i < num_tbs; i++) {
+		pci_unmap_single(dev, iwl_tfd_tb_get_addr(tfd, i),
+				iwl_tfd_tb_get_len(tfd, i), PCI_DMA_TODEVICE);
+
+		if (txq->txb) {
+			dev_kfree_skb(txq->txb[txq->q.read_ptr].skb[i - 1]);
+			txq->txb[txq->q.read_ptr].skb[i - 1] = NULL;
+		}
+	}
+}
+
+int iwl_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv,
+				 struct iwl_tx_queue *txq,
+				 dma_addr_t addr, u16 len,
+				 u8 reset, u8 pad)
+{
+	struct iwl_queue *q;
+	struct iwl_tfd *tfd;
+	u32 num_tbs;
+
+	q = &txq->q;
+	tfd = &txq->tfds[q->write_ptr];
+
+	if (reset)
+		memset(tfd, 0, sizeof(*tfd));
+
+	num_tbs = iwl_tfd_get_num_tbs(tfd);
+
+	/* Each TFD can point to a maximum 20 Tx buffers */
+	if (num_tbs >= IWL_NUM_OF_TBS) {
+		IWL_ERR(priv, "Error can not send more than %d chunks\n",
+			  IWL_NUM_OF_TBS);
+		return -EINVAL;
+	}
+
+	BUG_ON(addr & ~DMA_BIT_MASK(36));
+	if (unlikely(addr & ~IWL_TX_DMA_MASK))
+		IWL_ERR(priv, "Unaligned address = %llx\n",
+			  (unsigned long long)addr);
+
+	iwl_tfd_set_tb(tfd, num_tbs, addr, len);
+
+	return 0;
+}
+
 /******************************************************************************
  *
  * Misc. internal state and helper functions

drivers/net/wireless/iwlwifi/iwl-core.h

@@ -110,6 +110,12 @@ struct iwl_lib_ops {
 	void (*txq_inval_byte_cnt_tbl)(struct iwl_priv *priv,
 				       struct iwl_tx_queue *txq);
 	void (*txq_set_sched)(struct iwl_priv *priv, u32 mask);
+	int (*txq_attach_buf_to_tfd)(struct iwl_priv *priv,
+				     struct iwl_tx_queue *txq,
+				     dma_addr_t addr,
+				     u16 len, u8 reset, u8 pad);
+	void (*txq_free_tfd)(struct iwl_priv *priv,
+			     struct iwl_tx_queue *txq);
 	/* aggregations */
 	int (*txq_agg_enable)(struct iwl_priv *priv, int txq_id, int tx_fifo,
 			      int sta_id, int tid, u16 ssn_idx);
@@ -252,6 +258,10 @@ void iwl_rx_statistics(struct iwl_priv *priv,
 * TX
 ******************************************************/
 int iwl_txq_ctx_reset(struct iwl_priv *priv);
+void iwl_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq);
+int iwl_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv,
+				 struct iwl_tx_queue *txq,
+				 dma_addr_t addr, u16 len, u8 reset, u8 pad);
 int iwl_tx_skb(struct iwl_priv *priv, struct sk_buff *skb);
 void iwl_hw_txq_ctx_free(struct iwl_priv *priv);
 int iwl_txq_update_write_ptr(struct iwl_priv *priv, struct iwl_tx_queue *txq);