Bluetooth: btintel_pcie: Add additional to checks to clear TX/RX paths

[ Upstream commit 1c76649 ]

Due to a hardware issue, there is a possibility that the driver may miss
an MSIx interrupt on the RX/TX data path. Since the TX and RX paths are
independent, when a TX MSIx interrupt occurs, the driver can check the
RX queue for any pending data and process it if present. The same
approach applies to the RX path.

Fixes: c2b636b ("Bluetooth: btintel_pcie: Add support for PCIe transport")
Signed-off-by: Chandrashekar Devegowda <[email protected]>
Signed-off-by: Kiran K <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Author: kirankrishnappa-intel

drivers/bluetooth/btintel_pcie.c

@@ -761,10 +761,8 @@ static void btintel_pcie_msix_rx_handle(struct btintel_pcie_data *data)
 	bt_dev_dbg(hdev, "RXQ: cr_hia: %u  cr_tia: %u", cr_hia, cr_tia);
 
 	/* Check CR_TIA and CR_HIA for change */
-	if (cr_tia == cr_hia) {
-		bt_dev_warn(hdev, "RXQ: no new CD found");
+	if (cr_tia == cr_hia)
 		return;
-	}
 
 	rxq = &data->rxq;
 
@@ -800,6 +798,16 @@ static irqreturn_t btintel_pcie_msix_isr(int irq, void *data)
 	return IRQ_WAKE_THREAD;
 }
 
+static inline bool btintel_pcie_is_rxq_empty(struct btintel_pcie_data *data)
+{
+	return data->ia.cr_hia[BTINTEL_PCIE_RXQ_NUM] == data->ia.cr_tia[BTINTEL_PCIE_RXQ_NUM];
+}
+
+static inline bool btintel_pcie_is_txackq_empty(struct btintel_pcie_data *data)
+{
+	return data->ia.cr_tia[BTINTEL_PCIE_TXQ_NUM] == data->ia.cr_hia[BTINTEL_PCIE_TXQ_NUM];
+}
+
 static irqreturn_t btintel_pcie_irq_msix_handler(int irq, void *dev_id)
 {
 	struct msix_entry *entry = dev_id;
@@ -827,12 +835,18 @@ static irqreturn_t btintel_pcie_irq_msix_handler(int irq, void *dev_id)
 		btintel_pcie_msix_gp0_handler(data);
 
 	/* For TX */
-	if (intr_fh & BTINTEL_PCIE_MSIX_FH_INT_CAUSES_0)
+	if (intr_fh & BTINTEL_PCIE_MSIX_FH_INT_CAUSES_0) {
 		btintel_pcie_msix_tx_handle(data);
+		if (!btintel_pcie_is_rxq_empty(data))
+			btintel_pcie_msix_rx_handle(data);
+	}
 
 	/* For RX */
-	if (intr_fh & BTINTEL_PCIE_MSIX_FH_INT_CAUSES_1)
+	if (intr_fh & BTINTEL_PCIE_MSIX_FH_INT_CAUSES_1) {
 		btintel_pcie_msix_rx_handle(data);
+		if (!btintel_pcie_is_txackq_empty(data))
+			btintel_pcie_msix_tx_handle(data);
+	}
 
 	/*
 	 * Before sending the interrupt the HW disables it to prevent a nested