wil6210: add 3-MSI support

Extend MSI support to 3-MSI in order to load balance the tx\rx
interrupts between different cores.
use_msi module parameter has changed to n_msi. Usage:
- Set n_msi to 0 for using INTx
- Set n_msi to 1 for using single MSI
- Set n_msi to 3 for using 3-MSI

In 3-MSI configuration MSI 0 is used for TX interrupts, MSI 1
is used for RX interrupts and MSI 2 is used for MISC interrupts.

Signed-off-by: Alexei Avshalom Lazar <ailizaro@codeaurora.org>
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/wil6210/interrupt.c

@@ -625,6 +625,15 @@ static irqreturn_t wil6210_irq_misc_thread(int irq, void *cookie)
 
 	wil6210_unmask_irq_misc(wil, false);
 
+	/* in non-triple MSI case, this is done inside wil6210_thread_irq
+	 * because it has to be done after unmasking the pseudo.
+	 */
+	if (wil->n_msi == 3 && wil->suspend_resp_rcvd) {
+		wil_dbg_irq(wil, "set suspend_resp_comp to true\n");
+		wil->suspend_resp_comp = true;
+		wake_up_interruptible(&wil->wq);
+	}
+
 	return IRQ_HANDLED;
 }
 
@@ -782,6 +791,40 @@ static irqreturn_t wil6210_hardirq(int irq, void *cookie)
 	return rc;
 }
 
+static int wil6210_request_3msi(struct wil6210_priv *wil, int irq)
+{
+	int rc;
+
+	/* IRQ's are in the following order:
+	 * - Tx
+	 * - Rx
+	 * - Misc
+	 */
+	rc = request_irq(irq, wil->txrx_ops.irq_tx, IRQF_SHARED,
+			 WIL_NAME "_tx", wil);
+	if (rc)
+		return rc;
+
+	rc = request_irq(irq + 1, wil->txrx_ops.irq_rx, IRQF_SHARED,
+			 WIL_NAME "_rx", wil);
+	if (rc)
+		goto free0;
+
+	rc = request_threaded_irq(irq + 2, wil6210_irq_misc,
+				  wil6210_irq_misc_thread,
+				  IRQF_SHARED, WIL_NAME "_misc", wil);
+	if (rc)
+		goto free1;
+
+	return 0;
+free1:
+	free_irq(irq + 1, wil);
+free0:
+	free_irq(irq, wil);
+
+	return rc;
+}
+
 /* can't use wil_ioread32_and_clear because ICC value is not set yet */
 static inline void wil_clear32(void __iomem *addr)
 {
@@ -822,11 +865,12 @@ void wil6210_clear_halp(struct wil6210_priv *wil)
 	wil6210_unmask_halp(wil);
 }
 
-int wil6210_init_irq(struct wil6210_priv *wil, int irq, bool use_msi)
+int wil6210_init_irq(struct wil6210_priv *wil, int irq)
 {
 	int rc;
 
-	wil_dbg_misc(wil, "init_irq: %s\n", use_msi ? "MSI" : "INTx");
+	wil_dbg_misc(wil, "init_irq: %s, n_msi=%d\n",
+		     wil->n_msi ? "MSI" : "INTx", wil->n_msi);
 
 	if (wil->use_enhanced_dma_hw) {
 		wil->txrx_ops.irq_tx = wil6210_irq_tx_edma;
@@ -835,10 +879,14 @@ int wil6210_init_irq(struct wil6210_priv *wil, int irq, bool use_msi)
 		wil->txrx_ops.irq_tx = wil6210_irq_tx;
 		wil->txrx_ops.irq_rx = wil6210_irq_rx;
 	}
-	rc = request_threaded_irq(irq, wil6210_hardirq,
-				  wil6210_thread_irq,
-				  use_msi ? 0 : IRQF_SHARED,
-				  WIL_NAME, wil);
+
+	if (wil->n_msi == 3)
+		rc = wil6210_request_3msi(wil, irq);
+	else
+		rc = request_threaded_irq(irq, wil6210_hardirq,
+					  wil6210_thread_irq,
+					  wil->n_msi ? 0 : IRQF_SHARED,
+					  WIL_NAME, wil);
 	return rc;
 }
 
@@ -848,4 +896,8 @@ void wil6210_fini_irq(struct wil6210_priv *wil, int irq)
 
 	wil_mask_irq(wil);
 	free_irq(irq, wil);
+	if (wil->n_msi == 3) {
+		free_irq(irq + 1, wil);
+		free_irq(irq + 2, wil);
+	}
 }

drivers/net/wireless/ath/wil6210/main.c

@@ -1136,6 +1136,9 @@ void wil_refresh_fw_capabilities(struct wil6210_priv *wil)
 				     wil->platform_capa)) ?
 			BIT(WIL_PLATFORM_FEATURE_FW_EXT_CLK_CONTROL) : 0;
 
+		if (wil->n_msi == 3)
+			features |= BIT(WIL_PLATFORM_FEATURE_TRIPLE_MSI);
+
 		wil->platform_ops.set_features(wil->platform_handle, features);
 	}
 }

drivers/net/wireless/ath/wil6210/pcie_bus.c

@@ -24,9 +24,9 @@
 #include <linux/rtnetlink.h>
 #include <linux/pm_runtime.h>
 
-static bool use_msi = true;
-module_param(use_msi, bool, 0444);
-MODULE_PARM_DESC(use_msi, " Use MSI interrupt, default - true");
+static int n_msi = 1;
+module_param(n_msi, int, 0444);
+MODULE_PARM_DESC(n_msi, " Use MSI interrupt: 0 - use INTx, 1 - (default) - single, or 3");
 
 static bool ftm_mode;
 module_param(ftm_mode, bool, 0444);
@@ -150,12 +150,24 @@ int wil_set_capabilities(struct wil6210_priv *wil)
 
 void wil_disable_irq(struct wil6210_priv *wil)
 {
-	disable_irq(wil->pdev->irq);
+	int irq = wil->pdev->irq;
+
+	disable_irq(irq);
+	if (wil->n_msi == 3) {
+		disable_irq(irq + 1);
+		disable_irq(irq + 2);
+	}
 }
 
 void wil_enable_irq(struct wil6210_priv *wil)
 {
-	enable_irq(wil->pdev->irq);
+	int irq = wil->pdev->irq;
+
+	enable_irq(irq);
+	if (wil->n_msi == 3) {
+		enable_irq(irq + 1);
+		enable_irq(irq + 2);
+	}
 }
 
 static void wil_remove_all_additional_vifs(struct wil6210_priv *wil)
@@ -182,28 +194,47 @@ static int wil_if_pcie_enable(struct wil6210_priv *wil)
 	 * and only MSI should be used
 	 */
 	int msi_only = pdev->msi_enabled;
-	bool _use_msi = use_msi;
 
 	wil_dbg_misc(wil, "if_pcie_enable\n");
 
 	pci_set_master(pdev);
 
-	wil_dbg_misc(wil, "Setup %s interrupt\n", use_msi ? "MSI" : "INTx");
+	/* how many MSI interrupts to request? */
+	switch (n_msi) {
+	case 3:
+	case 1:
+		wil_dbg_misc(wil, "Setup %d MSI interrupts\n", n_msi);
+		break;
+	case 0:
+		wil_dbg_misc(wil, "MSI interrupts disabled, use INTx\n");
+		break;
+	default:
+		wil_err(wil, "Invalid n_msi=%d, default to 1\n", n_msi);
+		n_msi = 1;
+	}
+
+	if (n_msi == 3 &&
+	    pci_alloc_irq_vectors(pdev, n_msi, n_msi, PCI_IRQ_MSI) < n_msi) {
+		wil_err(wil, "3 MSI mode failed, try 1 MSI\n");
+		n_msi = 1;
+	}
 
-	if (use_msi && pci_enable_msi(pdev)) {
+	if (n_msi == 1 && pci_enable_msi(pdev)) {
 		wil_err(wil, "pci_enable_msi failed, use INTx\n");
-		_use_msi = false;
+		n_msi = 0;
 	}
 
-	if (!_use_msi && msi_only) {
+	wil->n_msi = n_msi;
+
+	if (wil->n_msi == 0 && msi_only) {
 		wil_err(wil, "Interrupt pin not routed, unable to use INTx\n");
 		rc = -ENODEV;
 		goto stop_master;
 	}
 
-	rc = wil6210_init_irq(wil, pdev->irq, _use_msi);
+	rc = wil6210_init_irq(wil, pdev->irq);
 	if (rc)
-		goto stop_master;
+		goto release_vectors;
 
 	/* need reset here to obtain MAC */
 	mutex_lock(&wil->mutex);
@@ -216,8 +247,9 @@ static int wil_if_pcie_enable(struct wil6210_priv *wil)
 
  release_irq:
 	wil6210_fini_irq(wil, pdev->irq);
-	/* safe to call if no MSI */
-	pci_disable_msi(pdev);
+ release_vectors:
+	/* safe to call if no allocation */
+	pci_free_irq_vectors(pdev);
  stop_master:
 	pci_clear_master(pdev);
 	return rc;

drivers/net/wireless/ath/wil6210/wil6210.h

@@ -874,6 +874,7 @@ struct wil6210_priv {
 	u32 bar_size;
 	struct wiphy *wiphy;
 	struct net_device *main_ndev;
+	int n_msi;
 	void __iomem *csr;
 	DECLARE_BITMAP(status, wil_status_last);
 	u8 fw_version[ETHTOOL_FWVERS_LEN];
@@ -1206,7 +1207,7 @@ int wil_addba_rx_request(struct wil6210_priv *wil, u8 mid,
 int wil_addba_tx_request(struct wil6210_priv *wil, u8 ringid, u16 wsize);
 
 void wil6210_clear_irq(struct wil6210_priv *wil);
-int wil6210_init_irq(struct wil6210_priv *wil, int irq, bool use_msi);
+int wil6210_init_irq(struct wil6210_priv *wil, int irq);
 void wil6210_fini_irq(struct wil6210_priv *wil, int irq);
 void wil_mask_irq(struct wil6210_priv *wil);
 void wil_unmask_irq(struct wil6210_priv *wil);

drivers/net/wireless/ath/wil6210/wil_platform.h

@@ -29,6 +29,7 @@ enum wil_platform_event {
 
 enum wil_platform_features {
 	WIL_PLATFORM_FEATURE_FW_EXT_CLK_CONTROL = 0,
+	WIL_PLATFORM_FEATURE_TRIPLE_MSI = 1,
 	WIL_PLATFORM_FEATURE_MAX,
 };