qcacmn: WAR for RXDMA packet drop issue

When monitor RXDMA is enabled, regular RXDMA will drop a good packet
whenever an error is indicated in monitor path due to a HW bug. To
avoid this, a dummy buffer will be used to receive packets passing
"monitor other" filter on regular DMA, which will be received on
RXDMA2HOST ring. These packets should be ignored based on a special
cookie value.

Change-Id: I348527f662cd664652d8d99c01484bb310c6e705

dp/wifi3.0/dp_rx_err.c

@@ -843,6 +843,8 @@ dp_rx_err_mpdu_pop(struct dp_soc *soc, uint32_t mac_id,
 	uint32_t msdu_cnt;
 	uint32_t i;
 	bool mpdu_err;
+	uint8_t push_reason;
+	uint8_t rxdma_error_code = 0;
 
 	msdu = 0;
 
@@ -851,6 +853,13 @@ dp_rx_err_mpdu_pop(struct dp_soc *soc, uint32_t mac_id,
 	hal_rx_reo_ent_buf_paddr_get(rxdma_dst_ring_desc, &buf_info,
 		&p_last_buf_addr_info, &msdu_cnt, &mpdu_err);
 
+	push_reason =
+		hal_rx_reo_ent_rxdma_push_reason_get(rxdma_dst_ring_desc);
+	if (push_reason == HAL_RX_WBM_RXDMA_PSH_RSN_ERROR) {
+		rxdma_error_code =
+			hal_rx_reo_ent_rxdma_error_code_get(rxdma_dst_ring_desc);
+	}
+
 	do {
 		rx_msdu_link_desc =
 			dp_rx_cookie_2_link_desc_va(soc, &buf_info);
@@ -864,11 +873,11 @@ dp_rx_err_mpdu_pop(struct dp_soc *soc, uint32_t mac_id,
 
 		msdu_cnt -= num_msdus;
 
-		for (i = 0; i < num_msdus; i++) {
-			struct dp_rx_desc *rx_desc =
-				dp_rx_cookie_2_va_rxdma_buf(soc,
-					msdu_list.sw_cookie[i]);
-
+		if (msdu_list.sw_cookie[0] != HAL_RX_COOKIE_SPECIAL) {
+			for (i = 0; i < num_msdus; i++) {
+				struct dp_rx_desc *rx_desc =
+					dp_rx_cookie_2_va_rxdma_buf(soc,
+						msdu_list.sw_cookie[i]);
 				qdf_assert(rx_desc);
 				msdu = rx_desc->nbuf;
 
@@ -884,6 +893,9 @@ dp_rx_err_mpdu_pop(struct dp_soc *soc, uint32_t mac_id,
 				rx_bufs_used++;
 				dp_rx_add_to_free_desc_list(head,
 					tail, rx_desc);
+			}
+		} else {
+			rxdma_error_code = HAL_RXDMA_ERR_WAR;
 		}
 
 		hal_rx_mon_next_link_desc_get(rx_msdu_link_desc, &buf_info,
@@ -894,6 +906,8 @@ dp_rx_err_mpdu_pop(struct dp_soc *soc, uint32_t mac_id,
 
 	} while (buf_info.paddr && msdu_cnt);
 
+	DP_STATS_INC(soc, rx.err.rxdma_error[rxdma_error_code], 1);
+
 	return rx_bufs_used;
 }
 

dp/wifi3.0/hal_rx.h

@@ -1633,6 +1633,10 @@ struct hal_buf_info {
 	uint32_t sw_cookie;
 };
 
+/* This special cookie value will be used to indicate FW allocated buffers
+ * received through RXDMA2SW ring for RXDMA WARs */
+#define HAL_RX_COOKIE_SPECIAL 0x1fffff
+
 /**
  * hal_rx_msdu_link_desc_get(): API to get the MSDU information
  * from the MSDU link descriptor
@@ -1795,6 +1799,7 @@ enum hal_reo_error_code {
  * @ HAL_RXDMA_ERR_DA_TIMEOUT    : Destination Address  search timeout
  * @ HAL_RXDMA_ERR_FLOW_TIMEOUT  : Flow Search Timeout
  * @ HAL_RXDMA_ERR_FLUSH_REQUEST : RxDMA FIFO Flush request
+ * @ HAL_RXDMA_ERR_WAR           : RxDMA WAR dummy errors
  */
 enum hal_rxdma_error_code {
 	HAL_RXDMA_ERR_OVERFLOW = 0,
@@ -1810,7 +1815,8 @@ enum hal_rxdma_error_code {
 	HAL_RXDMA_ERR_SA_TIMEOUT,
 	HAL_RXDMA_ERR_DA_TIMEOUT,
 	HAL_RXDMA_ERR_FLOW_TIMEOUT,
-	HAL_RXDMA_ERR_FLUSH_REQUEST
+	HAL_RXDMA_ERR_FLUSH_REQUEST,
+	HAL_RXDMA_ERR_WAR = 31
 };
 
 /**