mei: me: d0i3: enable d0i3 interrupts

D0i3 adds additional interrupt reason bit, therefore we add a variable
intr_source to save the interrupt causes for further dispatching.
The interrupt cause is saved in the irq quick handler to achieve
unified behavior for both MSI enabled and shared interrupt platforms.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/hw-me-regs.h

@@ -166,6 +166,10 @@
 /* Host D0I3 Interrupt Status */
 #define H_D0I3C_IS        0x00000040
 
+/* H_CSR masks */
+#define H_CSR_IE_MASK     (H_IE | H_D0I3C_IE)
+#define H_CSR_IS_MASK     (H_IS | H_D0I3C_IS)
+
 /* register bits of ME_CSR_HA (ME Control Status Host Access register) */
 /* ME CB (Circular Buffer) Depth HRA (Host Read Access) - host read only
 access to ME_CBD */

drivers/misc/mei/hw-me.c

@@ -134,7 +134,7 @@ static inline void mei_hcsr_write(struct mei_device *dev, u32 reg)
  */
 static inline void mei_hcsr_set(struct mei_device *dev, u32 reg)
 {
-	reg &= ~H_IS;
+	reg &= ~H_CSR_IS_MASK;
 	mei_hcsr_write(dev, reg);
 }
 
@@ -216,7 +216,7 @@ static void mei_me_intr_clear(struct mei_device *dev)
 {
 	u32 hcsr = mei_hcsr_read(dev);
 
-	if ((hcsr & H_IS) == H_IS)
+	if (hcsr & H_CSR_IS_MASK)
 		mei_hcsr_write(dev, hcsr);
 }
 /**
@@ -228,7 +228,7 @@ static void mei_me_intr_enable(struct mei_device *dev)
 {
 	u32 hcsr = mei_hcsr_read(dev);
 
-	hcsr |= H_IE;
+	hcsr |= H_CSR_IE_MASK;
 	mei_hcsr_set(dev, hcsr);
 }
 
@@ -241,7 +241,7 @@ static void mei_me_intr_disable(struct mei_device *dev)
 {
 	u32 hcsr = mei_hcsr_read(dev);
 
-	hcsr  &= ~H_IE;
+	hcsr  &= ~H_CSR_IE_MASK;
 	mei_hcsr_set(dev, hcsr);
 }
 
@@ -285,12 +285,12 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
 		hcsr = mei_hcsr_read(dev);
 	}
 
-	hcsr |= H_RST | H_IG | H_IS;
+	hcsr |= H_RST | H_IG | H_CSR_IS_MASK;
 
 	if (intr_enable)
-		hcsr |= H_IE;
+		hcsr |= H_CSR_IE_MASK;
 	else
-		hcsr &= ~H_IE;
+		hcsr &= ~H_CSR_IE_MASK;
 
 	dev->recvd_hw_ready = false;
 	mei_hcsr_write(dev, hcsr);
@@ -322,7 +322,7 @@ static void mei_me_host_set_ready(struct mei_device *dev)
 {
 	u32 hcsr = mei_hcsr_read(dev);
 
-	hcsr |= H_IE | H_IG | H_RDY;
+	hcsr |= H_CSR_IE_MASK | H_IG | H_RDY;
 	mei_hcsr_set(dev, hcsr);
 }
 
@@ -767,16 +767,20 @@ static void mei_me_pg_intr(struct mei_device *dev)
  *
  * Return: irqreturn_t
  */
-
 irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id)
 {
-	struct mei_device *dev = (struct mei_device *) dev_id;
-	u32 hcsr = mei_hcsr_read(dev);
+	struct mei_device *dev = (struct mei_device *)dev_id;
+	struct mei_me_hw *hw = to_me_hw(dev);
+	u32 hcsr;
 
-	if ((hcsr & H_IS) != H_IS)
+	hcsr = mei_hcsr_read(dev);
+	if (!(hcsr & H_CSR_IS_MASK))
 		return IRQ_NONE;
 
-	/* clear H_IS bit in H_CSR */
+	hw->intr_source = hcsr & H_CSR_IS_MASK;
+	dev_dbg(dev->dev, "interrupt source 0x%08X.\n", hw->intr_source);
+
+	/* clear H_IS and H_D0I3C_IS bits in H_CSR to clear the interrupts */
 	mei_hcsr_write(dev, hcsr);
 
 	return IRQ_WAKE_THREAD;
@@ -804,11 +808,6 @@ irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id)
 	mutex_lock(&dev->device_lock);
 	mei_io_list_init(&complete_list);
 
-	/* Ack the interrupt here
-	 * In case of MSI we don't go through the quick handler */
-	if (pci_dev_msi_enabled(to_pci_dev(dev->dev)))
-		mei_clear_interrupts(dev);
-
 	/* check if ME wants a reset */
 	if (!mei_hw_is_ready(dev) && dev->dev_state != MEI_DEV_RESETTING) {
 		dev_warn(dev->dev, "FW not ready: resetting.\n");

drivers/misc/mei/hw-me.h

@@ -51,12 +51,14 @@ struct mei_cfg {
  *
  * @cfg: per device generation config and ops
  * @mem_addr: io memory address
+ * @intr_source: interrupt source
  * @pg_state: power gating state
  * @d0i3_supported: di03 support
  */
 struct mei_me_hw {
 	const struct mei_cfg *cfg;
 	void __iomem *mem_addr;
+	u32 intr_source;
 	enum mei_pg_state pg_state;
 	bool d0i3_supported;
 };

drivers/misc/mei/pci-me.c

@@ -128,6 +128,7 @@ static int mei_me_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	const struct mei_cfg *cfg = (struct mei_cfg *)(ent->driver_data);
 	struct mei_device *dev;
 	struct mei_me_hw *hw;
+	unsigned int irqflags;
 	int err;
 
 
@@ -180,17 +181,12 @@ static int mei_me_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	pci_enable_msi(pdev);
 
 	 /* request and enable interrupt */
-	if (pci_dev_msi_enabled(pdev))
-		err = request_threaded_irq(pdev->irq,
-			NULL,
-			mei_me_irq_thread_handler,
-			IRQF_ONESHOT, KBUILD_MODNAME, dev);
-	else
+	irqflags = pci_dev_msi_enabled(pdev) ? IRQF_ONESHOT : IRQF_SHARED;
+
 	err = request_threaded_irq(pdev->irq,
 			mei_me_irq_quick_handler,
 			mei_me_irq_thread_handler,
-			IRQF_SHARED, KBUILD_MODNAME, dev);
-
+			irqflags, KBUILD_MODNAME, dev);
 	if (err) {
 		dev_err(&pdev->dev, "request_threaded_irq failure. irq = %d\n",
 		       pdev->irq);
@@ -319,6 +315,7 @@ static int mei_me_pci_resume(struct device *device)
 {
 	struct pci_dev *pdev = to_pci_dev(device);
 	struct mei_device *dev;
+	unsigned int irqflags;
 	int err;
 
 	dev = pci_get_drvdata(pdev);
@@ -327,17 +324,13 @@ static int mei_me_pci_resume(struct device *device)
 
 	pci_enable_msi(pdev);
 
+	irqflags = pci_dev_msi_enabled(pdev) ? IRQF_ONESHOT : IRQF_SHARED;
+
 	/* request and enable interrupt */
-	if (pci_dev_msi_enabled(pdev))
-		err = request_threaded_irq(pdev->irq,
-			NULL,
-			mei_me_irq_thread_handler,
-			IRQF_ONESHOT, KBUILD_MODNAME, dev);
-	else
 	err = request_threaded_irq(pdev->irq,
 			mei_me_irq_quick_handler,
 			mei_me_irq_thread_handler,
-			IRQF_SHARED, KBUILD_MODNAME, dev);
+			irqflags, KBUILD_MODNAME, dev);
 
 	if (err) {
 		dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",