[RFC v4 13/18] ath10k: htt: High latency TX support

[Erik Stromdahl <erik.stromdahl@gmail.com>]

Add HTT TX function for HL interfaces.
Intended for SDIO and USB.

Signed-off-by: Erik Stromdahl <erik.stromdahl@gmail.com>
---
 drivers/net/wireless/ath/ath10k/htt_tx.c | 92 ++++++++++++++++++++++++++++++++
 1 file changed, 92 insertions(+)

diff --git a/drivers/net/wireless/ath/ath10k/htt_tx.c b/drivers/net/wireless/ath/ath10k/htt_tx.c
index 1f6470de7b8d..7ea27454ef3f 100644
--- a/drivers/net/wireless/ath/ath10k/htt_tx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_tx.c
@@ -495,6 +495,9 @@ int ath10k_htt_tx_start(struct ath10k_htt *htt)
 	if (htt->tx_mem_allocated)
 		return 0;
 
+	if (ar->is_high_latency)
+		return 0;
+
 	ret = ath10k_htt_tx_alloc_buf(htt);
 	if (ret)
 		goto free_idr_pending_tx;
@@ -1188,6 +1191,94 @@ int ath10k_htt_mgmt_tx(struct ath10k_htt *htt, struct sk_buff *msdu)
 	return res;
 }
 
+#define HTT_TX_HL_NEEDED_HEADROOM \
+	(unsigned int)(sizeof(struct htt_cmd_hdr) + \
+	sizeof(struct htt_data_tx_desc) + \
+	sizeof(struct ath10k_htc_hdr))
+
+static int ath10k_htt_tx_hl(struct ath10k_htt *htt, enum ath10k_hw_txrx_mode txmode,
+			    struct sk_buff *msdu)
+{
+	struct ath10k *ar = htt->ar;
+	int res, data_len;
+	struct htt_cmd_hdr *cmd_hdr;
+	struct htt_data_tx_desc *tx_desc;
+	struct ath10k_skb_cb *skb_cb = ATH10K_SKB_CB(msdu);
+	struct sk_buff *tmp_skb;
+	bool is_eth = (txmode == ATH10K_HW_TXRX_ETHERNET);
+	u8 vdev_id = ath10k_htt_tx_get_vdev_id(ar, msdu);
+	u8 tid = ath10k_htt_tx_get_tid(msdu, is_eth);
+	u8 flags0 = 0;
+	u16 flags1 = 0;
+
+	data_len = msdu->len;
+
+	switch (txmode) {
+	case ATH10K_HW_TXRX_RAW:
+	case ATH10K_HW_TXRX_NATIVE_WIFI:
+		flags0 |= HTT_DATA_TX_DESC_FLAGS0_MAC_HDR_PRESENT;
+		/* fall through */
+	case ATH10K_HW_TXRX_ETHERNET:
+		flags0 |= SM(txmode, HTT_DATA_TX_DESC_FLAGS0_PKT_TYPE);
+		break;
+	case ATH10K_HW_TXRX_MGMT:
+		flags0 |= SM(ATH10K_HW_TXRX_MGMT,
+			     HTT_DATA_TX_DESC_FLAGS0_PKT_TYPE);
+		flags0 |= HTT_DATA_TX_DESC_FLAGS0_MAC_HDR_PRESENT;
+		break;
+	}
+
+	if (skb_cb->flags & ATH10K_SKB_F_NO_HWCRYPT)
+		flags0 |= HTT_DATA_TX_DESC_FLAGS0_NO_ENCRYPT;
+
+	flags1 |= SM((u16)vdev_id, HTT_DATA_TX_DESC_FLAGS1_VDEV_ID);
+	flags1 |= SM((u16)tid, HTT_DATA_TX_DESC_FLAGS1_EXT_TID);
+	if (msdu->ip_summed == CHECKSUM_PARTIAL &&
+	    !test_bit(ATH10K_FLAG_RAW_MODE, &ar->dev_flags)) {
+		flags1 |= HTT_DATA_TX_DESC_FLAGS1_CKSUM_L3_OFFLOAD;
+		flags1 |= HTT_DATA_TX_DESC_FLAGS1_CKSUM_L4_OFFLOAD;
+	}
+
+	/* Prepend the HTT header and TX desc struct to the data message
+	 * and realloc the skb if it does not have enough headroom.
+	 */
+	if (skb_headroom(msdu) < HTT_TX_HL_NEEDED_HEADROOM) {
+		tmp_skb = msdu;
+
+		ath10k_dbg(htt->ar, ATH10K_DBG_HTT,
+			   "Not enough headroom in skb. Current headroom: %u, needed: %u. Reallocating...\n",
+			   skb_headroom(msdu), HTT_TX_HL_NEEDED_HEADROOM);
+		msdu = skb_realloc_headroom(msdu, HTT_TX_HL_NEEDED_HEADROOM);
+		kfree_skb(tmp_skb);
+		if (!msdu) {
+			ath10k_warn(htt->ar, "htt hl tx: Unable to realloc skb!\n");
+			res = -ENOMEM;
+			goto out;
+		}
+	}
+
+	skb_push(msdu, sizeof(*cmd_hdr));
+	skb_push(msdu, sizeof(*tx_desc));
+	cmd_hdr = (struct htt_cmd_hdr *)msdu->data;
+	tx_desc = (struct htt_data_tx_desc *)(msdu->data + sizeof(*cmd_hdr));
+
+	cmd_hdr->msg_type = HTT_H2T_MSG_TYPE_TX_FRM;
+	tx_desc->flags0 = flags0;
+	tx_desc->flags1 = __cpu_to_le16(flags1);
+	tx_desc->len = __cpu_to_le16(data_len);
+	tx_desc->id = 0;
+	tx_desc->frags_paddr = 0; /* always zero */
+	/* Initialize peer_id to INVALID_PEER because this is NOT
+	 * Reinjection path
+	 */
+	tx_desc->peerid = __cpu_to_le32(HTT_INVALID_PEERID);
+
+	res = ath10k_htc_send(&htt->ar->htc, htt->eid, msdu);
+
+out:
+	return res;
+}
+
 static int ath10k_htt_tx_32(struct ath10k_htt *htt,
 			    enum ath10k_hw_txrx_mode txmode,
 			    struct sk_buff *msdu)
@@ -1619,6 +1710,7 @@ static const struct ath10k_htt_tx_ops htt_tx_ops_64 = {
 static const struct ath10k_htt_tx_ops htt_tx_ops_hl = {
 	.htt_send_rx_ring_cfg = ath10k_htt_send_rx_ring_cfg_hl,
 	.htt_send_frag_desc_bank_cfg = ath10k_htt_send_frag_desc_bank_cfg_32,
+	.htt_tx = ath10k_htt_tx_hl,
 };
 
 void ath10k_htt_set_tx_ops(struct ath10k_htt *htt)
-- 
2.15.1