ath11k: Disabling credit flow for WMI path

Firmware credit flow control is enabled for WMI control services,
which expects available tokens should be acquired before sending a
command to the target. Also the token gets released when firmware
receives the command.

This credit-based flow limits driver to send WMI command only
when the token available which is causing WMI commands to timeout and
return -EAGAIN, whereas firmware has enough capability to process the
WMI command. To fix this Tx starvation issue, introduce the ability to
disable the credit flow for the WMI path.

The driver sends WMI configuration for disabling credit flow to firmware
by two ways.
	1. By using a global flag
		(HTC_MSG_SETUP_COMPLETE_EX_ID msg type flags)
	2. By using a local flag
		(ATH11K_HTC_CONN_FLAGS_DISABLE_CREDIT_FLOW_CTRL = 1 << 3)

Ath11k uses both these configurations to disable credit flow for the
WMI path completely.

Also added a hw_param member for credit flow control by which we can
enable or disable it based on per-target basis. Currently we are disabling
credit flow for IPQ8074, IPQ6018, and QCN9074 as recommended by firmware.

Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.4.0.1-01492-QCAHKSWPL_SILICONZ-1
Tested-on: IPQ6018 hw1.0 AHB WLAN.HK.2.4.0.1-00330-QCAHKSWPL_SILICONZ-1

Co-developed-by: Pravas Kumar Panda <kumarpan@codeaurora.org>
Signed-off-by: Pravas Kumar Panda <kumarpan@codeaurora.org>
Signed-off-by: P Praneesh <quic_ppranees@quicinc.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1635156494-20059-1-git-send-email-quic_ppranees@quicinc.com

1 files changed, 30 insertions, 7 deletions

diff --git a/drivers/net/wireless/ath/ath11k/ce.c b/drivers/net/wireless/ath/ath11k/ce.c
index 3bc4242c1059..aaa7b05ff49d 100644
--- a/drivers/net/wireless/ath/ath11k/ce.c
+++ b/drivers/net/wireless/ath/ath11k/ce.c
@@ -14,6 +14,7 @@ const struct ce_attr ath11k_host_ce_config_ipq8074[] = {
 		.src_nentries = 16,
 		.src_sz_max = 2048,
 		.dest_nentries = 0,
+		.send_cb = ath11k_htc_tx_completion_handler,
 	},
 
 	/* CE1: target->host HTT + HTC control */
@@ -40,6 +41,7 @@ const struct ce_attr ath11k_host_ce_config_ipq8074[] = {
 		.src_nentries = 32,
 		.src_sz_max = 2048,
 		.dest_nentries = 0,
+		.send_cb = ath11k_htc_tx_completion_handler,
 	},
 
 	/* CE4: host->target HTT */
@@ -73,6 +75,7 @@ const struct ce_attr ath11k_host_ce_config_ipq8074[] = {
 		.src_nentries = 32,
 		.src_sz_max = 2048,
 		.dest_nentries = 0,
+		.send_cb = ath11k_htc_tx_completion_handler,
 	},
 
 	/* CE8: target autonomous hif_memcpy */
@@ -89,6 +92,7 @@ const struct ce_attr ath11k_host_ce_config_ipq8074[] = {
 		.src_nentries = 32,
 		.src_sz_max = 2048,
 		.dest_nentries = 0,
+		.send_cb = ath11k_htc_tx_completion_handler,
 	},
 
 	/* CE10: target->host HTT */
@@ -142,6 +146,7 @@ const struct ce_attr ath11k_host_ce_config_qca6390[] = {
 		.src_nentries = 32,
 		.src_sz_max = 2048,
 		.dest_nentries = 0,
+		.send_cb = ath11k_htc_tx_completion_handler,
 	},
 
 	/* CE4: host->target HTT */
@@ -175,6 +180,7 @@ const struct ce_attr ath11k_host_ce_config_qca6390[] = {
 		.src_nentries = 32,
 		.src_sz_max = 2048,
 		.dest_nentries = 0,
+		.send_cb = ath11k_htc_tx_completion_handler,
 	},
 
 	/* CE8: target autonomous hif_memcpy */
@@ -220,6 +226,7 @@ const struct ce_attr ath11k_host_ce_config_qcn9074[] = {
 		.src_nentries = 32,
 		.src_sz_max = 2048,
 		.dest_nentries = 0,
+		.send_cb = ath11k_htc_tx_completion_handler,
 	},
 
 	/* CE4: host->target HTT */
@@ -489,18 +496,32 @@ err_unlock:
 	return skb;
 }
 
-static void ath11k_ce_send_done_cb(struct ath11k_ce_pipe *pipe)
+static void ath11k_ce_tx_process_cb(struct ath11k_ce_pipe *pipe)
 {
 	struct ath11k_base *ab = pipe->ab;
 	struct sk_buff *skb;
+	struct sk_buff_head list;
 
+	__skb_queue_head_init(&list);
 	while (!IS_ERR(skb = ath11k_ce_completed_send_next(pipe))) {
 		if (!skb)
 			continue;
 
 		dma_unmap_single(ab->dev, ATH11K_SKB_CB(skb)->paddr, skb->len,
 				 DMA_TO_DEVICE);
-		dev_kfree_skb_any(skb);
+
+		if ((!pipe->send_cb) || ab->hw_params.credit_flow) {
+			dev_kfree_skb_any(skb);
+			continue;
+		}
+
+		__skb_queue_tail(&list, skb);
+	}
+
+	while ((skb = __skb_dequeue(&list))) {
+		ath11k_dbg(ab, ATH11K_DBG_AHB, "tx ce pipe %d len %d\n",
+			   pipe->pipe_num, skb->len);
+		pipe->send_cb(ab, skb);
 	}
 }
 
@@ -636,7 +657,7 @@ static int ath11k_ce_alloc_pipe(struct ath11k_base *ab, int ce_id)
 	pipe->attr_flags = attr->flags;
 
 	if (attr->src_nentries) {
-		pipe->send_cb = ath11k_ce_send_done_cb;
+		pipe->send_cb = attr->send_cb;
 		nentries = roundup_pow_of_two(attr->src_nentries);
 		desc_sz = ath11k_hal_ce_get_desc_size(HAL_CE_DESC_SRC);
 		ring = ath11k_ce_alloc_ring(ab, nentries, desc_sz);
@@ -667,9 +688,10 @@ static int ath11k_ce_alloc_pipe(struct ath11k_base *ab, int ce_id)
 void ath11k_ce_per_engine_service(struct ath11k_base *ab, u16 ce_id)
 {
 	struct ath11k_ce_pipe *pipe = &ab->ce.ce_pipe[ce_id];
+	const struct ce_attr *attr = &ab->hw_params.host_ce_config[ce_id];
 
-	if (pipe->send_cb)
-		pipe->send_cb(pipe);
+	if (attr->src_nentries)
+		ath11k_ce_tx_process_cb(pipe);
 
 	if (pipe->recv_cb)
 		ath11k_ce_recv_process_cb(pipe);
@@ -678,9 +700,10 @@ void ath11k_ce_per_engine_service(struct ath11k_base *ab, u16 ce_id)
 void ath11k_ce_poll_send_completed(struct ath11k_base *ab, u8 pipe_id)
 {
 	struct ath11k_ce_pipe *pipe = &ab->ce.ce_pipe[pipe_id];
+	const struct ce_attr *attr =  &ab->hw_params.host_ce_config[pipe_id];
 
-	if ((pipe->attr_flags & CE_ATTR_DIS_INTR) && pipe->send_cb)
-		pipe->send_cb(pipe);
+	if ((pipe->attr_flags & CE_ATTR_DIS_INTR) && attr->src_nentries)
+		ath11k_ce_tx_process_cb(pipe);
 }
 EXPORT_SYMBOL(ath11k_ce_per_engine_service);