iwlagn: move Tx datapath to transport layer
Split the Tx datapath in two parts:
* the first deals with the Tx cmd composition
* the second attaches the skb + Tx cmd to the queues
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-trans.c b/drivers/net/wireless/iwlwifi/iwl-trans.c
index d760857..acd2a5f 100644
--- a/drivers/net/wireless/iwlwifi/iwl-trans.c
+++ b/drivers/net/wireless/iwlwifi/iwl-trans.c
@@ -552,6 +552,159 @@
return 0;
}
+static struct iwl_tx_cmd *iwl_trans_get_tx_cmd(struct iwl_priv *priv,
+ int txq_id)
+{
+ struct iwl_tx_queue *txq = &priv->txq[txq_id];
+ struct iwl_queue *q = &txq->q;
+ struct iwl_device_cmd *dev_cmd;
+
+ if (unlikely(iwl_queue_space(q) < q->high_mark))
+ return NULL;
+
+ /*
+ * Set up the Tx-command (not MAC!) header.
+ * Store the chosen Tx queue and TFD index within the sequence field;
+ * after Tx, uCode's Tx response will return this value so driver can
+ * locate the frame within the tx queue and do post-tx processing.
+ */
+ dev_cmd = txq->cmd[q->write_ptr];
+ memset(dev_cmd, 0, sizeof(*dev_cmd));
+ dev_cmd->hdr.cmd = REPLY_TX;
+ dev_cmd->hdr.sequence = cpu_to_le16((u16)(QUEUE_TO_SEQ(txq_id) |
+ INDEX_TO_SEQ(q->write_ptr)));
+ return &dev_cmd->cmd.tx;
+}
+
+static int iwl_trans_tx(struct iwl_priv *priv, struct sk_buff *skb,
+ struct iwl_tx_cmd *tx_cmd, int txq_id, __le16 fc, bool ampdu,
+ struct iwl_rxon_context *ctx)
+{
+ struct iwl_tx_queue *txq = &priv->txq[txq_id];
+ struct iwl_queue *q = &txq->q;
+ struct iwl_device_cmd *dev_cmd = txq->cmd[q->write_ptr];
+ struct iwl_cmd_meta *out_meta;
+
+ dma_addr_t phys_addr = 0;
+ dma_addr_t txcmd_phys;
+ dma_addr_t scratch_phys;
+ u16 len, firstlen, secondlen;
+ u8 wait_write_ptr = 0;
+ u8 hdr_len = ieee80211_hdrlen(fc);
+
+ /* Set up driver data for this TFD */
+ memset(&(txq->txb[q->write_ptr]), 0, sizeof(struct iwl_tx_info));
+ txq->txb[q->write_ptr].skb = skb;
+ txq->txb[q->write_ptr].ctx = ctx;
+
+ /* Set up first empty entry in queue's array of Tx/cmd buffers */
+ out_meta = &txq->meta[q->write_ptr];
+
+ /*
+ * Use the first empty entry in this queue's command buffer array
+ * to contain the Tx command and MAC header concatenated together
+ * (payload data will be in another buffer).
+ * Size of this varies, due to varying MAC header length.
+ * If end is not dword aligned, we'll have 2 extra bytes at the end
+ * of the MAC header (device reads on dword boundaries).
+ * We'll tell device about this padding later.
+ */
+ len = sizeof(struct iwl_tx_cmd) +
+ sizeof(struct iwl_cmd_header) + hdr_len;
+ firstlen = (len + 3) & ~3;
+
+ /* Tell NIC about any 2-byte padding after MAC header */
+ if (firstlen != len)
+ tx_cmd->tx_flags |= TX_CMD_FLG_MH_PAD_MSK;
+
+ /* Physical address of this Tx command's header (not MAC header!),
+ * within command buffer array. */
+ txcmd_phys = dma_map_single(priv->bus.dev,
+ &dev_cmd->hdr, firstlen,
+ DMA_BIDIRECTIONAL);
+ if (unlikely(dma_mapping_error(priv->bus.dev, txcmd_phys)))
+ return -1;
+ dma_unmap_addr_set(out_meta, mapping, txcmd_phys);
+ dma_unmap_len_set(out_meta, len, firstlen);
+
+ if (!ieee80211_has_morefrags(fc)) {
+ txq->need_update = 1;
+ } else {
+ wait_write_ptr = 1;
+ txq->need_update = 0;
+ }
+
+ /* Set up TFD's 2nd entry to point directly to remainder of skb,
+ * if any (802.11 null frames have no payload). */
+ secondlen = skb->len - hdr_len;
+ if (secondlen > 0) {
+ phys_addr = dma_map_single(priv->bus.dev, skb->data + hdr_len,
+ secondlen, DMA_TO_DEVICE);
+ if (unlikely(dma_mapping_error(priv->bus.dev, phys_addr))) {
+ dma_unmap_single(priv->bus.dev,
+ dma_unmap_addr(out_meta, mapping),
+ dma_unmap_len(out_meta, len),
+ DMA_BIDIRECTIONAL);
+ return -1;
+ }
+ }
+
+ /* Attach buffers to TFD */
+ iwlagn_txq_attach_buf_to_tfd(priv, txq, txcmd_phys, firstlen, 1);
+ if (secondlen > 0)
+ iwlagn_txq_attach_buf_to_tfd(priv, txq, phys_addr,
+ secondlen, 0);
+
+ scratch_phys = txcmd_phys + sizeof(struct iwl_cmd_header) +
+ offsetof(struct iwl_tx_cmd, scratch);
+
+ /* take back ownership of DMA buffer to enable update */
+ dma_sync_single_for_cpu(priv->bus.dev, txcmd_phys, firstlen,
+ DMA_BIDIRECTIONAL);
+ tx_cmd->dram_lsb_ptr = cpu_to_le32(scratch_phys);
+ tx_cmd->dram_msb_ptr = iwl_get_dma_hi_addr(scratch_phys);
+
+ IWL_DEBUG_TX(priv, "sequence nr = 0X%x\n",
+ le16_to_cpu(dev_cmd->hdr.sequence));
+ IWL_DEBUG_TX(priv, "tx_flags = 0X%x\n", le32_to_cpu(tx_cmd->tx_flags));
+ iwl_print_hex_dump(priv, IWL_DL_TX, (u8 *)tx_cmd, sizeof(*tx_cmd));
+ iwl_print_hex_dump(priv, IWL_DL_TX, (u8 *)tx_cmd->hdr, hdr_len);
+
+ /* Set up entry for this TFD in Tx byte-count array */
+ if (ampdu)
+ iwlagn_txq_update_byte_cnt_tbl(priv, txq,
+ le16_to_cpu(tx_cmd->len));
+
+ dma_sync_single_for_device(priv->bus.dev, txcmd_phys, firstlen,
+ DMA_BIDIRECTIONAL);
+
+ trace_iwlwifi_dev_tx(priv,
+ &((struct iwl_tfd *)txq->tfds)[txq->q.write_ptr],
+ sizeof(struct iwl_tfd),
+ &dev_cmd->hdr, firstlen,
+ skb->data + hdr_len, secondlen);
+
+ /* Tell device the write index *just past* this latest filled TFD */
+ q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd);
+ iwl_txq_update_write_ptr(priv, txq);
+
+ /*
+ * At this point the frame is "transmitted" successfully
+ * and we will get a TX status notification eventually,
+ * regardless of the value of ret. "ret" only indicates
+ * whether or not we should update the write pointer.
+ */
+ if ((iwl_queue_space(q) < q->high_mark) && priv->mac80211_registered) {
+ if (wait_write_ptr) {
+ txq->need_update = 1;
+ iwl_txq_update_write_ptr(priv, txq);
+ } else {
+ iwl_stop_queue(priv, txq);
+ }
+ }
+ return 0;
+}
+
static const struct iwl_trans_ops trans_ops = {
.rx_init = iwl_trans_rx_init,
.rx_stop = iwl_trans_rx_stop,
@@ -563,6 +716,9 @@
.send_cmd = iwl_send_cmd,
.send_cmd_pdu = iwl_send_cmd_pdu,
+
+ .get_tx_cmd = iwl_trans_get_tx_cmd,
+ .tx = iwl_trans_tx,
};
void iwl_trans_register(struct iwl_trans *trans)
