ath11k: Add dp tx err stats

Add support for dp tx error stats which logs tx failure reasons due
to ring full condition, etc. This stats is added in soc_dp_stats
which was earlier used as soc_rx_stats so that all dp related info
are logged in same file.

Below is an example usage,

root@OpenWrt:/# cat /sys/kernel/debug/ath11k/ipq8074/soc_dp_stats
SOC RX STATS:

err ring pkts: 0
Invalid RBM: 0
<snip>

SOC TX STATS:

Ring Full Failures:
ring0: 4
ring1: 3
ring2: 5

Misc Transmit Failures: 2

Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.1.0.1-01213-QCAHKSWPL_SILICONZ-1
Signed-off-by: Sriram R <srirrama@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1591768308-32005-2-git-send-email-srirrama@codeaurora.org

drivers/net/wireless/ath/ath11k/core.h

@@ -590,12 +590,22 @@ struct ath11k_board_data {
 /* IPQ8074 HW channel counters frequency value in hertz */
 #define IPQ8074_CC_FREQ_HERTZ 320000
 
-struct ath11k_soc_dp_rx_stats {
+struct ath11k_soc_dp_tx_err_stats {
+	/* TCL Ring Descriptor unavailable */
+	u32 desc_na[DP_TCL_NUM_RING_MAX];
+	/* Other failures during dp_tx due to mem allocation failure
+	 * idr unavailable etc.
+	 */
+	atomic_t misc_fail;
+};
+
+struct ath11k_soc_dp_stats {
 	u32 err_ring_pkts;
 	u32 invalid_rbm;
 	u32 rxdma_error[HAL_REO_ENTR_RING_RXDMA_ECODE_MAX];
 	u32 reo_error[HAL_REO_DEST_RING_ERROR_CODE_MAX];
 	u32 hal_reo_error[DP_REO_DST_RING_MAX];
+	struct ath11k_soc_dp_tx_err_stats tx_err;
 };
 
 /* Master structure to hold the hw data which may be used in core module */
@@ -664,7 +674,7 @@ struct ath11k_base {
 	struct dentry *debugfs_soc;
 	struct dentry *debugfs_ath11k;
 #endif
-	struct ath11k_soc_dp_rx_stats soc_stats;
+	struct ath11k_soc_dp_stats soc_stats;
 
 	unsigned long dev_flags;
 	struct completion driver_recovery;

drivers/net/wireless/ath/ath11k/debug.c

@@ -739,12 +739,12 @@ static const struct file_operations fops_extd_rx_stats = {
 	.open = simple_open,
 };
 
-static ssize_t ath11k_debug_dump_soc_rx_stats(struct file *file,
+static ssize_t ath11k_debug_dump_soc_dp_stats(struct file *file,
 					      char __user *user_buf,
 					      size_t count, loff_t *ppos)
 {
 	struct ath11k_base *ab = file->private_data;
-	struct ath11k_soc_dp_rx_stats *soc_stats = &ab->soc_stats;
+	struct ath11k_soc_dp_stats *soc_stats = &ab->soc_stats;
 	int len = 0, i, retval;
 	const int size = 4096;
 	static const char *rxdma_err[HAL_REO_ENTR_RING_RXDMA_ECODE_MAX] = {
@@ -788,6 +788,17 @@ static ssize_t ath11k_debug_dump_soc_rx_stats(struct file *file,
 			 soc_stats->hal_reo_error[2],
 			 soc_stats->hal_reo_error[3]);
 
+	len += scnprintf(buf + len, size - len, "\nSOC TX STATS:\n");
+	len += scnprintf(buf + len, size - len, "\nTCL Ring Full Failures:\n");
+
+	for (i = 0; i < DP_TCL_NUM_RING_MAX; i++)
+		len += scnprintf(buf + len, size - len, "ring%d: %u\n",
+				 i, soc_stats->tx_err.desc_na[i]);
+
+	len += scnprintf(buf + len, size - len,
+			 "\nMisc Transmit Failures: %d\n",
+			 atomic_read(&soc_stats->tx_err.misc_fail));
+
 	if (len > size)
 		len = size;
 	retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
@@ -796,8 +807,8 @@ static ssize_t ath11k_debug_dump_soc_rx_stats(struct file *file,
 	return retval;
 }
 
-static const struct file_operations fops_soc_rx_stats = {
-	.read = ath11k_debug_dump_soc_rx_stats,
+static const struct file_operations fops_soc_dp_stats = {
+	.read = ath11k_debug_dump_soc_dp_stats,
 	.open = simple_open,
 	.owner = THIS_MODULE,
 	.llseek = default_llseek,
@@ -819,8 +830,8 @@ int ath11k_debug_pdev_create(struct ath11k_base *ab)
 	debugfs_create_file("simulate_fw_crash", 0600, ab->debugfs_soc, ab,
 			    &fops_simulate_fw_crash);
 
-	debugfs_create_file("soc_rx_stats", 0600, ab->debugfs_soc, ab,
-			    &fops_soc_rx_stats);
+	debugfs_create_file("soc_dp_stats", 0600, ab->debugfs_soc, ab,
+			    &fops_soc_dp_stats);
 
 	return 0;
 }

drivers/net/wireless/ath/ath11k/dp_tx.c

@@ -121,8 +121,10 @@ int ath11k_dp_tx(struct ath11k *ar, struct ath11k_vif *arvif,
 	spin_unlock_bh(&tx_ring->tx_idr_lock);
 
 	if (ret < 0) {
-		if (ring_map == (BIT(DP_TCL_NUM_RING_MAX) - 1))
+		if (ring_map == (BIT(DP_TCL_NUM_RING_MAX) - 1)) {
+			atomic_inc(&ab->soc_stats.tx_err.misc_fail);
 			return -ENOSPC;
+		}
 
 		/* Check if the next ring is available */
 		ring_selector++;
@@ -180,11 +182,13 @@ int ath11k_dp_tx(struct ath11k *ar, struct ath11k_vif *arvif,
 	default:
 		/* TODO: Take care of other encap modes as well */
 		ret = -EINVAL;
+		atomic_inc(&ab->soc_stats.tx_err.misc_fail);
 		goto fail_remove_idr;
 	}
 
 	ti.paddr = dma_map_single(ab->dev, skb->data, skb->len, DMA_TO_DEVICE);
 	if (dma_mapping_error(ab->dev, ti.paddr)) {
+		atomic_inc(&ab->soc_stats.tx_err.misc_fail);
 		ath11k_warn(ab, "failed to DMA map data Tx buffer\n");
 		ret = -ENOMEM;
 		goto fail_remove_idr;
@@ -208,6 +212,7 @@ int ath11k_dp_tx(struct ath11k *ar, struct ath11k_vif *arvif,
 		 * desc because the desc is directly enqueued onto hw queue.
 		 */
 		ath11k_hal_srng_access_end(ab, tcl_ring);
+		ab->soc_stats.tx_err.desc_na[ti.ring_id]++;
 		spin_unlock_bh(&tcl_ring->lock);
 		ret = -ENOMEM;