diff mbox

[v3,04/16] wcn36xx: add dxe.c

Message ID 1377676606-23033-5-git-send-email-k.eugene.e@gmail.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Eugene Krasnikov Aug. 28, 2013, 7:56 a.m. UTC
add dxe.c

Signed-off-by: Eugene Krasnikov <k.eugene.e@gmail.com>
---
 drivers/net/wireless/ath/wcn36xx/dxe.c | 804 +++++++++++++++++++++++++++++++++
 1 file changed, 804 insertions(+)
 create mode 100644 drivers/net/wireless/ath/wcn36xx/dxe.c
diff mbox

Patch

diff --git a/drivers/net/wireless/ath/wcn36xx/dxe.c b/drivers/net/wireless/ath/wcn36xx/dxe.c
new file mode 100644
index 0000000..db1f413
--- /dev/null
+++ b/drivers/net/wireless/ath/wcn36xx/dxe.c
@@ -0,0 +1,804 @@ 
+/*
+ * Copyright (c) 2013 Eugene Krasnikov <k.eugene.e@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* DXE - DMA transfer engine
+ * we have 2 channels(High prio and Low prio) for TX and 2 channels for RX.
+ * through low channels data packets are transfered
+ * through high channels managment packets are transfered
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/interrupt.h>
+#include "wcn36xx.h"
+#include "txrx.h"
+
+void *wcn36xx_dxe_get_next_bd(struct wcn36xx *wcn, bool is_low)
+{
+	struct wcn36xx_dxe_ch *ch = is_low ?
+		&wcn->dxe_tx_l_ch :
+		&wcn->dxe_tx_h_ch;
+
+	return ch->head_blk_ctl->bd_cpu_addr;
+}
+
+static void wcn36xx_dxe_write_register(struct wcn36xx *wcn, int addr, int data)
+{
+	wcn36xx_dbg(WCN36XX_DBG_DXE,
+		    "wcn36xx_dxe_write_register: addr=%x, data=%x\n",
+		    addr, data);
+
+	writel(data, wcn->mmio + addr);
+}
+
+static void wcn36xx_dxe_read_register(struct wcn36xx *wcn, int addr, int *data)
+{
+	*data = readl(wcn->mmio + addr);
+
+	wcn36xx_dbg(WCN36XX_DBG_DXE,
+		    "wcn36xx_dxe_read_register: addr=%x, data=%x\n",
+		    addr, *data);
+}
+
+static void wcn36xx_dxe_free_ctl_block(struct wcn36xx_dxe_ch *ch)
+{
+	struct wcn36xx_dxe_ctl *ctl = ch->head_blk_ctl, *next;
+	int i;
+
+	for (i = 0; i < ch->desc_num && ctl; i++) {
+		next = ctl->next;
+		kfree(ctl);
+		ctl = next;
+	}
+}
+
+static int wcn36xx_dxe_allocate_ctl_block(struct wcn36xx_dxe_ch *ch)
+{
+	struct wcn36xx_dxe_ctl *prev_ctl = NULL;
+	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
+	int i;
+
+	for (i = 0; i < ch->desc_num; i++) {
+		cur_ctl = kzalloc(sizeof(*cur_ctl), GFP_KERNEL);
+		if (!cur_ctl)
+			goto out_fail;
+
+		cur_ctl->ctl_blk_order = i;
+		if (i == 0) {
+			ch->head_blk_ctl = cur_ctl;
+			ch->tail_blk_ctl = cur_ctl;
+		} else if (ch->desc_num - 1 == i) {
+			prev_ctl->next = cur_ctl;
+			cur_ctl->next = ch->head_blk_ctl;
+		} else {
+			prev_ctl->next = cur_ctl;
+		}
+		prev_ctl = cur_ctl;
+	}
+
+	return 0;
+
+out_fail:
+	wcn36xx_dxe_free_ctl_block(ch);
+	return -ENOMEM;
+}
+
+int wcn36xx_dxe_alloc_ctl_blks(struct wcn36xx *wcn)
+{
+	int ret;
+
+	wcn->dxe_tx_l_ch.ch_type = WCN36XX_DXE_CH_TX_L;
+	wcn->dxe_tx_h_ch.ch_type = WCN36XX_DXE_CH_TX_H;
+	wcn->dxe_rx_l_ch.ch_type = WCN36XX_DXE_CH_RX_L;
+	wcn->dxe_rx_h_ch.ch_type = WCN36XX_DXE_CH_RX_H;
+
+	wcn->dxe_tx_l_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_TX_L;
+	wcn->dxe_tx_h_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_TX_H;
+	wcn->dxe_rx_l_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_RX_L;
+	wcn->dxe_rx_h_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_RX_H;
+
+	wcn->dxe_tx_l_ch.dxe_wq =  WCN36XX_DXE_WQ_TX_L;
+	wcn->dxe_tx_h_ch.dxe_wq =  WCN36XX_DXE_WQ_TX_H;
+
+	wcn->dxe_tx_l_ch.ctrl_bd = WCN36XX_DXE_CTRL_TX_L_BD;
+	wcn->dxe_tx_h_ch.ctrl_bd = WCN36XX_DXE_CTRL_TX_H_BD;
+
+	wcn->dxe_tx_l_ch.ctrl_skb = WCN36XX_DXE_CTRL_TX_L_SKB;
+	wcn->dxe_tx_h_ch.ctrl_skb = WCN36XX_DXE_CTRL_TX_H_SKB;
+
+	wcn->dxe_tx_l_ch.reg_ctrl = WCN36XX_DXE_REG_CTL_TX_L;
+	wcn->dxe_tx_h_ch.reg_ctrl = WCN36XX_DXE_REG_CTL_TX_H;
+
+	wcn->dxe_tx_l_ch.def_ctrl = WCN36XX_DXE_CH_DEFAULT_CTL_TX_L;
+	wcn->dxe_tx_h_ch.def_ctrl = WCN36XX_DXE_CH_DEFAULT_CTL_TX_H;
+
+	/* DXE control block allocation */
+	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_tx_l_ch);
+	if (ret)
+		goto out_err;
+	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_tx_h_ch);
+	if (ret)
+		goto out_err;
+	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_rx_l_ch);
+	if (ret)
+		goto out_err;
+	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_rx_h_ch);
+	if (ret)
+		goto out_err;
+
+	/* Initialize SMSM state  Clear TX Enable RING EMPTY STATE */
+	ret = wcn->ctrl_ops->smsm_change_state(
+		WCN36XX_SMSM_WLAN_TX_ENABLE,
+		WCN36XX_SMSM_WLAN_TX_RINGS_EMPTY);
+
+	return 0;
+
+out_err:
+	wcn36xx_err("Failed to allocate DXE control blocks\n");
+	wcn36xx_dxe_free_ctl_blks(wcn);
+	return -ENOMEM;
+}
+
+void wcn36xx_dxe_free_ctl_blks(struct wcn36xx *wcn)
+{
+	wcn36xx_dxe_free_ctl_block(&wcn->dxe_tx_l_ch);
+	wcn36xx_dxe_free_ctl_block(&wcn->dxe_tx_h_ch);
+	wcn36xx_dxe_free_ctl_block(&wcn->dxe_rx_l_ch);
+	wcn36xx_dxe_free_ctl_block(&wcn->dxe_rx_h_ch);
+}
+
+static int wcn36xx_dxe_init_descs(struct wcn36xx_dxe_ch *wcn_ch)
+{
+	struct wcn36xx_dxe_desc *cur_dxe = NULL;
+	struct wcn36xx_dxe_desc *prev_dxe = NULL;
+	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
+	size_t size;
+	int i;
+
+	size = wcn_ch->desc_num * sizeof(struct wcn36xx_dxe_desc);
+	wcn_ch->cpu_addr = dma_alloc_coherent(NULL, size, &wcn_ch->dma_addr,
+					      GFP_KERNEL);
+	if (!wcn_ch->cpu_addr)
+		return -ENOMEM;
+
+	memset(wcn_ch->cpu_addr, 0, size);
+
+	cur_dxe = (struct wcn36xx_dxe_desc *)wcn_ch->cpu_addr;
+	cur_ctl = wcn_ch->head_blk_ctl;
+
+	for (i = 0; i < wcn_ch->desc_num; i++) {
+		cur_ctl->desc = cur_dxe;
+		cur_ctl->desc_phy_addr = wcn_ch->dma_addr +
+			i * sizeof(struct wcn36xx_dxe_desc);
+
+		switch (wcn_ch->ch_type) {
+		case WCN36XX_DXE_CH_TX_L:
+			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_L;
+			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_L;
+			break;
+		case WCN36XX_DXE_CH_TX_H:
+			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_H;
+			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_H;
+			break;
+		case WCN36XX_DXE_CH_RX_L:
+			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_L;
+			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_L;
+			break;
+		case WCN36XX_DXE_CH_RX_H:
+			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_H;
+			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_H;
+			break;
+		}
+		if (0 == i) {
+			cur_dxe->phy_next_l = 0;
+		} else if ((0 < i) && (i < wcn_ch->desc_num - 1)) {
+			prev_dxe->phy_next_l =
+				cur_ctl->desc_phy_addr;
+		} else if (i == (wcn_ch->desc_num - 1)) {
+			prev_dxe->phy_next_l =
+				cur_ctl->desc_phy_addr;
+			cur_dxe->phy_next_l =
+				wcn_ch->head_blk_ctl->desc_phy_addr;
+		}
+		cur_ctl = cur_ctl->next;
+		prev_dxe = cur_dxe;
+		cur_dxe++;
+	}
+
+	return 0;
+}
+
+static void wcn36xx_dxe_init_tx_bd(struct wcn36xx_dxe_ch *ch,
+				   struct wcn36xx_dxe_mem_pool *pool)
+{
+	int i, chunk_size = pool->chunk_size;
+	dma_addr_t bd_phy_addr = pool->phy_addr;
+	void *bd_cpu_addr = pool->virt_addr;
+	struct wcn36xx_dxe_ctl *cur = ch->head_blk_ctl;
+
+	for (i = 0; i < ch->desc_num; i++) {
+		/* Only every second dxe needs a bd pointer,
+		   the other will point to the skb data */
+		if (!(i & 1)) {
+			cur->bd_phy_addr = bd_phy_addr;
+			cur->bd_cpu_addr = bd_cpu_addr;
+			bd_phy_addr += chunk_size;
+			bd_cpu_addr += chunk_size;
+		} else {
+			cur->bd_phy_addr = 0;
+			cur->bd_cpu_addr = NULL;
+		}
+		cur = cur->next;
+	}
+}
+
+static int wcn36xx_dxe_enable_ch_int(struct wcn36xx *wcn, u16 wcn_ch)
+{
+	int reg_data = 0;
+
+	wcn36xx_dxe_read_register(wcn,
+				  WCN36XX_DXE_INT_MASK_REG,
+				  &reg_data);
+
+	reg_data |= wcn_ch;
+
+	wcn36xx_dxe_write_register(wcn,
+				   WCN36XX_DXE_INT_MASK_REG,
+				   (int)reg_data);
+	return 0;
+}
+
+static int wcn36xx_dxe_fill_skb(struct wcn36xx_dxe_ctl *ctl)
+{
+	struct wcn36xx_dxe_desc *dxe = ctl->desc;
+	struct sk_buff *skb;
+
+	skb = alloc_skb(WCN36XX_PKT_SIZE, GFP_ATOMIC);
+	if (skb == NULL)
+		return -ENOMEM;
+
+	dxe->dst_addr_l = dma_map_single(NULL,
+					 skb_tail_pointer(skb),
+					 WCN36XX_PKT_SIZE,
+					 DMA_FROM_DEVICE);
+	ctl->skb = skb;
+
+	return 0;
+}
+
+static int wcn36xx_dxe_ch_alloc_skb(struct wcn36xx *wcn,
+				    struct wcn36xx_dxe_ch *wcn_ch)
+{
+	int i;
+	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
+
+	cur_ctl = wcn_ch->head_blk_ctl;
+
+	for (i = 0; i < wcn_ch->desc_num; i++) {
+		wcn36xx_dxe_fill_skb(cur_ctl);
+		cur_ctl = cur_ctl->next;
+	}
+
+	return 0;
+}
+
+static void wcn36xx_dxe_ch_free_skbs(struct wcn36xx *wcn,
+				     struct wcn36xx_dxe_ch *wcn_ch)
+{
+	struct wcn36xx_dxe_ctl *cur = wcn_ch->head_blk_ctl;
+	int i;
+
+	for (i = 0; i < wcn_ch->desc_num; i++) {
+		kfree_skb(cur->skb);
+		cur = cur->next;
+	}
+}
+
+void wcn36xx_dxe_tx_ack_ind(struct wcn36xx *wcn, u32 status)
+{
+	struct ieee80211_tx_info *info;
+	struct sk_buff *skb;
+	unsigned long flags;
+
+	spin_lock_irqsave(&wcn->dxe_lock, flags);
+	skb = wcn->tx_ack_skb;
+	wcn->tx_ack_skb = NULL;
+	spin_unlock_irqrestore(&wcn->dxe_lock, flags);
+
+	if (!skb) {
+		wcn36xx_warn("Spurious TX complete indication\n");
+		return;
+	}
+
+	info = IEEE80211_SKB_CB(skb);
+
+	if (status == 1)
+		info->flags |= IEEE80211_TX_STAT_ACK;
+
+	wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ack status: %d\n", status);
+
+	ieee80211_tx_status_irqsafe(wcn->hw, skb);
+	ieee80211_wake_queues(wcn->hw);
+}
+
+static void reap_tx_dxes(struct wcn36xx *wcn, struct wcn36xx_dxe_ch *ch)
+{
+	struct wcn36xx_dxe_ctl *ctl = ch->tail_blk_ctl;
+	struct ieee80211_tx_info *info;
+	unsigned long flags;
+
+	/*
+	 * Make at least one loop of do-while because in case ring is
+	 * completely full head and tail are pointing to the same element
+	 * and while-do will not make any cycles.
+	 */
+	do {
+		if (ctl->skb) {
+			dma_unmap_single(NULL, ctl->desc->src_addr_l,
+					 ctl->skb->len, DMA_TO_DEVICE);
+			info = IEEE80211_SKB_CB(ctl->skb);
+			if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) {
+				/* Keep frame until TX status comes */
+				ieee80211_free_txskb(wcn->hw, ctl->skb);
+			}
+			spin_lock_irqsave(&ctl->skb_lock, flags);
+			if (wcn->queues_stopped) {
+				wcn->queues_stopped = false;
+				ieee80211_wake_queues(wcn->hw);
+			}
+			spin_unlock_irqrestore(&ctl->skb_lock, flags);
+
+			ctl->skb = NULL;
+		}
+		ctl = ctl->next;
+	} while (ctl != ch->head_blk_ctl &&
+	       !(ctl->desc->ctrl & WCN36XX_DXE_CTRL_VALID_MASK));
+
+	ch->tail_blk_ctl = ctl;
+}
+
+static irqreturn_t wcn36xx_irq_tx_complete(int irq, void *dev)
+{
+	struct wcn36xx *wcn = (struct wcn36xx *)dev;
+	int int_src, int_reason;
+
+	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
+
+	if (int_src & WCN36XX_INT_MASK_CHAN_TX_H) {
+		wcn36xx_dxe_read_register(wcn,
+					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_H,
+					  &int_reason);
+
+		/* TODO: Check int_reason */
+
+		wcn36xx_dxe_write_register(wcn,
+					   WCN36XX_DXE_0_INT_CLR,
+					   WCN36XX_INT_MASK_CHAN_TX_H);
+
+		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_ED_CLR,
+					   WCN36XX_INT_MASK_CHAN_TX_H);
+		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready high\n");
+		reap_tx_dxes(wcn, &wcn->dxe_tx_h_ch);
+	}
+
+	if (int_src & WCN36XX_INT_MASK_CHAN_TX_L) {
+		wcn36xx_dxe_read_register(wcn,
+					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_L,
+					  &int_reason);
+		/* TODO: Check int_reason */
+
+		wcn36xx_dxe_write_register(wcn,
+					   WCN36XX_DXE_0_INT_CLR,
+					   WCN36XX_INT_MASK_CHAN_TX_L);
+
+		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_ED_CLR,
+					   WCN36XX_INT_MASK_CHAN_TX_L);
+		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready low\n");
+		reap_tx_dxes(wcn, &wcn->dxe_tx_l_ch);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t wcn36xx_irq_rx_ready(int irq, void *dev)
+{
+	struct wcn36xx *wcn = (struct wcn36xx *)dev;
+
+	disable_irq_nosync(wcn->rx_irq);
+	wcn36xx_dxe_rx_frame(wcn);
+	enable_irq(wcn->rx_irq);
+	return IRQ_HANDLED;
+}
+
+static int wcn36xx_dxe_request_irqs(struct wcn36xx *wcn)
+{
+	int ret;
+
+	ret = request_irq(wcn->tx_irq, wcn36xx_irq_tx_complete,
+			  IRQF_TRIGGER_HIGH, "wcn36xx_tx", wcn);
+	if (ret) {
+		wcn36xx_err("failed to alloc tx irq\n");
+		goto out_err;
+	}
+
+	ret = request_irq(wcn->rx_irq, wcn36xx_irq_rx_ready, IRQF_TRIGGER_HIGH,
+			  "wcn36xx_rx", wcn);
+	if (ret) {
+		wcn36xx_err("failed to alloc rx irq\n");
+		goto out_txirq;
+	}
+
+	enable_irq_wake(wcn->rx_irq);
+
+	return 0;
+
+out_txirq:
+	free_irq(wcn->tx_irq, wcn);
+out_err:
+	return ret;
+
+}
+
+static int wcn36xx_rx_handle_packets(struct wcn36xx *wcn,
+				     struct wcn36xx_dxe_ch *ch)
+{
+	struct wcn36xx_dxe_ctl *ctl = ch->head_blk_ctl;
+	struct wcn36xx_dxe_desc *dxe = ctl->desc;
+	dma_addr_t  dma_addr;
+	struct sk_buff *skb;
+
+	while (!(dxe->ctrl & WCN36XX_DXE_CTRL_VALID_MASK)) {
+		skb = ctl->skb;
+		dma_addr = dxe->dst_addr_l;
+		wcn36xx_dxe_fill_skb(ctl);
+
+		switch (ch->ch_type) {
+		case WCN36XX_DXE_CH_RX_L:
+			dxe->ctrl = WCN36XX_DXE_CTRL_RX_L;
+			wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_ENCH_ADDR,
+						   WCN36XX_DXE_INT_CH1_MASK);
+			break;
+		case WCN36XX_DXE_CH_RX_H:
+			dxe->ctrl = WCN36XX_DXE_CTRL_RX_H;
+			wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_ENCH_ADDR,
+						   WCN36XX_DXE_INT_CH3_MASK);
+			break;
+		default:
+			wcn36xx_warn("Unknown channel\n");
+		}
+
+		dma_unmap_single(NULL, dma_addr, WCN36XX_PKT_SIZE,
+				 DMA_FROM_DEVICE);
+		wcn36xx_rx_skb(wcn, skb);
+		ctl = ctl->next;
+		dxe = ctl->desc;
+	}
+
+	ch->head_blk_ctl = ctl;
+
+	return 0;
+}
+
+void wcn36xx_dxe_rx_frame(struct wcn36xx *wcn)
+{
+	int int_src;
+
+	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
+
+	/* RX_LOW_PRI */
+	if (int_src & WCN36XX_DXE_INT_CH1_MASK) {
+		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR,
+					   WCN36XX_DXE_INT_CH1_MASK);
+		wcn36xx_rx_handle_packets(wcn, &(wcn->dxe_rx_l_ch));
+	}
+
+	/* RX_HIGH_PRI */
+	if (int_src & WCN36XX_DXE_INT_CH3_MASK) {
+		/* Clean up all the INT within this channel */
+		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR,
+					   WCN36XX_DXE_INT_CH3_MASK);
+		wcn36xx_rx_handle_packets(wcn, &(wcn->dxe_rx_h_ch));
+	}
+
+	if (!int_src)
+		wcn36xx_warn("No DXE interrupt pending\n");
+}
+
+int wcn36xx_dxe_allocate_mem_pools(struct wcn36xx *wcn)
+{
+	size_t s;
+	void *cpu_addr;
+
+	/* Allocate BD headers for MGMT frames */
+
+	/* Where this come from ask QC */
+	wcn->mgmt_mem_pool.chunk_size =	WCN36XX_BD_CHUNK_SIZE +
+		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
+
+	s = wcn->mgmt_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_H;
+	cpu_addr = dma_alloc_coherent(NULL, s, &wcn->mgmt_mem_pool.phy_addr,
+				      GFP_KERNEL);
+	if (!cpu_addr)
+		goto out_err;
+
+	wcn->mgmt_mem_pool.virt_addr = cpu_addr;
+	memset(cpu_addr, 0, s);
+
+	/* Allocate BD headers for DATA frames */
+
+	/* Where this come from ask QC */
+	wcn->data_mem_pool.chunk_size = WCN36XX_BD_CHUNK_SIZE +
+		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
+
+	s = wcn->data_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_L;
+	cpu_addr = dma_alloc_coherent(NULL, s, &wcn->data_mem_pool.phy_addr,
+				      GFP_KERNEL);
+	if (!cpu_addr)
+		goto out_err;
+
+	wcn->data_mem_pool.virt_addr = cpu_addr;
+	memset(cpu_addr, 0, s);
+
+	return 0;
+
+out_err:
+	wcn36xx_dxe_free_mem_pools(wcn);
+	wcn36xx_err("Failed to allocate BD mempool\n");
+	return -ENOMEM;
+}
+
+void wcn36xx_dxe_free_mem_pools(struct wcn36xx *wcn)
+{
+	if (wcn->mgmt_mem_pool.virt_addr)
+		dma_free_coherent(NULL, wcn->mgmt_mem_pool.chunk_size *
+				  WCN36XX_DXE_CH_DESC_NUMB_TX_H,
+				  wcn->mgmt_mem_pool.virt_addr,
+				  wcn->mgmt_mem_pool.phy_addr);
+
+	if (wcn->data_mem_pool.virt_addr) {
+		dma_free_coherent(NULL, wcn->data_mem_pool.chunk_size *
+				  WCN36XX_DXE_CH_DESC_NUMB_TX_L,
+				  wcn->data_mem_pool.virt_addr,
+				  wcn->data_mem_pool.phy_addr);
+	}
+}
+
+int wcn36xx_dxe_tx_frame(struct wcn36xx *wcn,
+			 struct sk_buff *skb,
+			 bool is_low)
+{
+	struct wcn36xx_dxe_ctl *ctl = NULL;
+	struct wcn36xx_dxe_desc *desc = NULL;
+	struct wcn36xx_dxe_ch *ch = NULL;
+	unsigned long flags;
+
+	ch = is_low ? &wcn->dxe_tx_l_ch : &wcn->dxe_tx_h_ch;
+
+	ctl = ch->head_blk_ctl;
+
+	spin_lock_irqsave(&ctl->next->skb_lock, flags);
+
+	/*
+	 * If skb is not null that means that we reached the tail of the ring
+	 * hence ring is full. Stop queues to let mac80211 back off until ring
+	 * has an empty slot again.
+	 */
+	if (NULL != ctl->next->skb) {
+		ieee80211_stop_queues(wcn->hw);
+		wcn->queues_stopped = true;
+		spin_unlock_irqrestore(&ctl->next->skb_lock, flags);
+		return -EBUSY;
+	}
+	spin_unlock_irqrestore(&ctl->next->skb_lock, flags);
+
+	ctl->skb = NULL;
+	desc = ctl->desc;
+
+	/* Set source address of the BD we send */
+	desc->src_addr_l = ctl->bd_phy_addr;
+
+	desc->dst_addr_l = ch->dxe_wq;
+	desc->fr_len = sizeof(struct wcn36xx_tx_bd);
+	desc->ctrl = ch->ctrl_bd;
+
+	wcn36xx_dbg(WCN36XX_DBG_DXE, "DXE TX\n");
+
+	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC1 >>> ",
+			 (char *)desc, sizeof(*desc));
+	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP,
+			 "BD   >>> ", (char *)ctl->bd_cpu_addr,
+			 sizeof(struct wcn36xx_tx_bd));
+
+	/* Set source address of the SKB we send */
+	ctl = ctl->next;
+	ctl->skb = skb;
+	desc = ctl->desc;
+	if (ctl->bd_cpu_addr) {
+		wcn36xx_err("bd_cpu_addr cannot be NULL for skb DXE\n");
+		return -EINVAL;
+	}
+
+	desc->src_addr_l = dma_map_single(NULL,
+					  ctl->skb->data,
+					  ctl->skb->len,
+					  DMA_TO_DEVICE);
+
+	desc->dst_addr_l = ch->dxe_wq;
+	desc->fr_len = ctl->skb->len;
+
+	/* set dxe descriptor to VALID */
+	desc->ctrl = ch->ctrl_skb;
+
+	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC2 >>> ",
+			 (char *)desc, sizeof(*desc));
+	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "SKB   >>> ",
+			 (char *)ctl->skb->data, ctl->skb->len);
+
+	/* Move the head of the ring to the next empty descriptor */
+	 ch->head_blk_ctl = ctl->next;
+
+	/*
+	 * When connected and trying to send data frame chip can be in sleep
+	 * mode and writing to the register will not wake up the chip. Instead
+	 * notify chip about new frame through SMSM bus.
+	 */
+	if (wcn->pw_state == WCN36XX_BMPS) {
+		wcn->ctrl_ops->smsm_change_state(
+				  0,
+				  WCN36XX_SMSM_WLAN_TX_ENABLE);
+	} else {
+		/* indicate End Of Packet and generate interrupt on descriptor
+		 * done.
+		 */
+		wcn36xx_dxe_write_register(wcn,
+			ch->reg_ctrl, ch->def_ctrl);
+	}
+
+	return 0;
+}
+
+int wcn36xx_dxe_init(struct wcn36xx *wcn)
+{
+	int reg_data = 0, ret;
+
+	reg_data = WCN36XX_DXE_REG_RESET;
+	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_REG_CSR_RESET, reg_data);
+
+	/* Setting interrupt path */
+	reg_data = WCN36XX_DXE_CCU_INT;
+	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_REG_CCU_INT, reg_data);
+
+	/***************************************/
+	/* Init descriptors for TX LOW channel */
+	/***************************************/
+	wcn36xx_dxe_init_descs(&wcn->dxe_tx_l_ch);
+	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_l_ch, &wcn->data_mem_pool);
+
+	/* Write channel head to a NEXT register */
+	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_L,
+		wcn->dxe_tx_l_ch.head_blk_ctl->desc_phy_addr);
+
+	/* Program DMA destination addr for TX LOW */
+	wcn36xx_dxe_write_register(wcn,
+		WCN36XX_DXE_CH_DEST_ADDR_TX_L,
+		WCN36XX_DXE_WQ_TX_L);
+
+	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
+	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_L);
+
+	/***************************************/
+	/* Init descriptors for TX HIGH channel */
+	/***************************************/
+	wcn36xx_dxe_init_descs(&wcn->dxe_tx_h_ch);
+	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_h_ch, &wcn->mgmt_mem_pool);
+
+	/* Write channel head to a NEXT register */
+	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_H,
+		wcn->dxe_tx_h_ch.head_blk_ctl->desc_phy_addr);
+
+	/* Program DMA destination addr for TX HIGH */
+	wcn36xx_dxe_write_register(wcn,
+		WCN36XX_DXE_CH_DEST_ADDR_TX_H,
+		WCN36XX_DXE_WQ_TX_H);
+
+	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
+
+	/* Enable channel interrupts */
+	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_H);
+
+	/***************************************/
+	/* Init descriptors for RX LOW channel */
+	/***************************************/
+	wcn36xx_dxe_init_descs(&wcn->dxe_rx_l_ch);
+
+	/* For RX we need to preallocated buffers */
+	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_l_ch);
+
+	/* Write channel head to a NEXT register */
+	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_L,
+		wcn->dxe_rx_l_ch.head_blk_ctl->desc_phy_addr);
+
+	/* Write DMA source address */
+	wcn36xx_dxe_write_register(wcn,
+		WCN36XX_DXE_CH_SRC_ADDR_RX_L,
+		WCN36XX_DXE_WQ_RX_L);
+
+	/* Program preallocated destination address */
+	wcn36xx_dxe_write_register(wcn,
+		WCN36XX_DXE_CH_DEST_ADDR_RX_L,
+		wcn->dxe_rx_l_ch.head_blk_ctl->desc->phy_next_l);
+
+	/* Enable default control registers */
+	wcn36xx_dxe_write_register(wcn,
+		WCN36XX_DXE_REG_CTL_RX_L,
+		WCN36XX_DXE_CH_DEFAULT_CTL_RX_L);
+
+	/* Enable channel interrupts */
+	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_L);
+
+	/***************************************/
+	/* Init descriptors for RX HIGH channel */
+	/***************************************/
+	wcn36xx_dxe_init_descs(&wcn->dxe_rx_h_ch);
+
+	/* For RX we need to prealocat buffers */
+	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_h_ch);
+
+	/* Write chanel head to a NEXT register */
+	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_H,
+		wcn->dxe_rx_h_ch.head_blk_ctl->desc_phy_addr);
+
+	/* Write DMA source address */
+	wcn36xx_dxe_write_register(wcn,
+		WCN36XX_DXE_CH_SRC_ADDR_RX_H,
+		WCN36XX_DXE_WQ_RX_H);
+
+	/* Program preallocated destination address */
+	wcn36xx_dxe_write_register(wcn,
+		WCN36XX_DXE_CH_DEST_ADDR_RX_H,
+		 wcn->dxe_rx_h_ch.head_blk_ctl->desc->phy_next_l);
+
+	/* Enable default control registers */
+	wcn36xx_dxe_write_register(wcn,
+		WCN36XX_DXE_REG_CTL_RX_H,
+		WCN36XX_DXE_CH_DEFAULT_CTL_RX_H);
+
+	/* Enable channel interrupts */
+	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_H);
+
+	ret = wcn36xx_dxe_request_irqs(wcn);
+	if (ret < 0)
+		goto out_err;
+
+	return 0;
+
+out_err:
+	return ret;
+}
+
+void wcn36xx_dxe_deinit(struct wcn36xx *wcn)
+{
+	free_irq(wcn->tx_irq, wcn);
+	free_irq(wcn->rx_irq, wcn);
+
+	if (wcn->tx_ack_skb) {
+		ieee80211_tx_status_irqsafe(wcn->hw, wcn->tx_ack_skb);
+		wcn->tx_ack_skb = NULL;
+	}
+
+	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_l_ch);
+	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_h_ch);
+}