ioatdma: channel reset scheme fixup on Intel Atom S1200 platforms

The Intel Atom S1200 family ioatdma changed the channel reset behavior.
It does a reset similar to PCI FLR by resetting all the MSIX
registers. We have to re-init msix interrupts because of this. This
workaround is only specific to this platform and is not expected to carry
over to the later generations.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <djbw@fb.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/ioat/dma.c

@@ -892,7 +892,7 @@ MODULE_PARM_DESC(ioat_interrupt_style,
  * ioat_dma_setup_interrupts - setup interrupt handler
  * @device: ioat device
  */
-static int ioat_dma_setup_interrupts(struct ioatdma_device *device)
+int ioat_dma_setup_interrupts(struct ioatdma_device *device)
 {
 	struct ioat_chan_common *chan;
 	struct pci_dev *pdev = device->pdev;
@@ -941,6 +941,7 @@ msix:
 		}
 	}
 	intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL;
+	device->irq_mode = IOAT_MSIX;
 	goto done;
 
 msix_single_vector:
@@ -956,6 +957,7 @@ msix_single_vector:
 		pci_disable_msix(pdev);
 		goto msi;
 	}
+	device->irq_mode = IOAT_MSIX_SINGLE;
 	goto done;
 
 msi:
@@ -969,6 +971,7 @@ msi:
 		pci_disable_msi(pdev);
 		goto intx;
 	}
+	device->irq_mode = IOAT_MSIX;
 	goto done;
 
 intx:
@@ -977,6 +980,7 @@ intx:
 	if (err)
 		goto err_no_irq;
 
+	device->irq_mode = IOAT_INTX;
 done:
 	if (device->intr_quirk)
 		device->intr_quirk(device);
@@ -987,9 +991,11 @@ done:
 err_no_irq:
 	/* Disable all interrupt generation */
 	writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
+	device->irq_mode = IOAT_NOIRQ;
 	dev_err(dev, "no usable interrupts\n");
 	return err;
 }
+EXPORT_SYMBOL(ioat_dma_setup_interrupts);
 
 static void ioat_disable_interrupts(struct ioatdma_device *device)
 {

drivers/dma/ioat/dma.h

@@ -48,6 +48,14 @@
  */
 #define NULL_DESC_BUFFER_SIZE 1
 
+enum ioat_irq_mode {
+	IOAT_NOIRQ = 0,
+	IOAT_MSIX,
+	IOAT_MSIX_SINGLE,
+	IOAT_MSI,
+	IOAT_INTX
+};
+
 /**
  * struct ioatdma_device - internal representation of a IOAT device
  * @pdev: PCI-Express device
@@ -77,6 +85,7 @@ struct ioatdma_device {
 	struct msix_entry msix_entries[4];
 	struct ioat_chan_common *idx[4];
 	struct dca_provider *dca;
+	enum ioat_irq_mode irq_mode;
 	void (*intr_quirk)(struct ioatdma_device *device);
 	int (*enumerate_channels)(struct ioatdma_device *device);
 	int (*reset_hw)(struct ioat_chan_common *chan);
@@ -341,6 +350,7 @@ bool ioat_cleanup_preamble(struct ioat_chan_common *chan,
 			   dma_addr_t *phys_complete);
 void ioat_kobject_add(struct ioatdma_device *device, struct kobj_type *type);
 void ioat_kobject_del(struct ioatdma_device *device);
+int ioat_dma_setup_interrupts(struct ioatdma_device *device);
 extern const struct sysfs_ops ioat_sysfs_ops;
 extern struct ioat_sysfs_entry ioat_version_attr;
 extern struct ioat_sysfs_entry ioat_cap_attr;

drivers/dma/ioat/dma_v3.c

@@ -111,6 +111,103 @@ static void pq_set_src(struct ioat_raw_descriptor *descs[2],
 	pq->coef[idx] = coef;
 }
 
+static bool is_jf_ioat(struct pci_dev *pdev)
+{
+	switch (pdev->device) {
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF0:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF1:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF2:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF3:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF4:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF5:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF6:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF7:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF8:
+	case PCI_DEVICE_ID_INTEL_IOAT_JSF9:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool is_snb_ioat(struct pci_dev *pdev)
+{
+	switch (pdev->device) {
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB0:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB1:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB2:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB3:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB4:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB5:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB6:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB7:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB8:
+	case PCI_DEVICE_ID_INTEL_IOAT_SNB9:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool is_ivb_ioat(struct pci_dev *pdev)
+{
+	switch (pdev->device) {
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB0:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB1:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB2:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB3:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB4:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB5:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB6:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB7:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB8:
+	case PCI_DEVICE_ID_INTEL_IOAT_IVB9:
+		return true;
+	default:
+		return false;
+	}
+
+}
+
+static bool is_hsw_ioat(struct pci_dev *pdev)
+{
+	switch (pdev->device) {
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW0:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW1:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW2:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW3:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW4:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW5:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW6:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW7:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW8:
+	case PCI_DEVICE_ID_INTEL_IOAT_HSW9:
+		return true;
+	default:
+		return false;
+	}
+
+}
+
+static bool is_xeon_cb32(struct pci_dev *pdev)
+{
+	return is_jf_ioat(pdev) || is_snb_ioat(pdev) || is_ivb_ioat(pdev) ||
+		is_hsw_ioat(pdev);
+}
+
+static bool is_bwd_ioat(struct pci_dev *pdev)
+{
+	switch (pdev->device) {
+	case PCI_DEVICE_ID_INTEL_IOAT_BWD0:
+	case PCI_DEVICE_ID_INTEL_IOAT_BWD1:
+	case PCI_DEVICE_ID_INTEL_IOAT_BWD2:
+	case PCI_DEVICE_ID_INTEL_IOAT_BWD3:
+		return true;
+	default:
+		return false;
+	}
+}
+
 static void ioat3_dma_unmap(struct ioat2_dma_chan *ioat,
 			    struct ioat_ring_ent *desc, int idx)
 {
@@ -1168,6 +1265,56 @@ static int ioat3_dma_self_test(struct ioatdma_device *device)
 	return 0;
 }
 
+static int ioat3_irq_reinit(struct ioatdma_device *device)
+{
+	int msixcnt = device->common.chancnt;
+	struct pci_dev *pdev = device->pdev;
+	int i;
+	struct msix_entry *msix;
+	struct ioat_chan_common *chan;
+	int err = 0;
+
+	switch (device->irq_mode) {
+	case IOAT_MSIX:
+
+		for (i = 0; i < msixcnt; i++) {
+			msix = &device->msix_entries[i];
+			chan = ioat_chan_by_index(device, i);
+			devm_free_irq(&pdev->dev, msix->vector, chan);
+		}
+
+		pci_disable_msix(pdev);
+		break;
+
+	case IOAT_MSIX_SINGLE:
+		msix = &device->msix_entries[0];
+		chan = ioat_chan_by_index(device, 0);
+		devm_free_irq(&pdev->dev, msix->vector, chan);
+		pci_disable_msix(pdev);
+		break;
+
+	case IOAT_MSI:
+		chan = ioat_chan_by_index(device, 0);
+		devm_free_irq(&pdev->dev, pdev->irq, chan);
+		pci_disable_msi(pdev);
+		break;
+
+	case IOAT_INTX:
+		chan = ioat_chan_by_index(device, 0);
+		devm_free_irq(&pdev->dev, pdev->irq, chan);
+		break;
+
+	default:
+		return 0;
+	}
+
+	device->irq_mode = IOAT_NOIRQ;
+
+	err = ioat_dma_setup_interrupts(device);
+
+	return err;
+}
+
 static int ioat3_reset_hw(struct ioat_chan_common *chan)
 {
 	/* throw away whatever the channel was doing and get it
@@ -1199,91 +1346,16 @@ static int ioat3_reset_hw(struct ioat_chan_common *chan)
 	if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0)
 		pci_write_config_dword(pdev, IOAT_PCI_DMAUNCERRSTS_OFFSET, 0x10);
 
-	return ioat2_reset_sync(chan, msecs_to_jiffies(200));
-}
-
-static bool is_jf_ioat(struct pci_dev *pdev)
-{
-	switch (pdev->device) {
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF0:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF1:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF2:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF3:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF4:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF5:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF6:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF7:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF8:
-	case PCI_DEVICE_ID_INTEL_IOAT_JSF9:
-		return true;
-	default:
-		return false;
-	}
-}
-
-static bool is_snb_ioat(struct pci_dev *pdev)
-{
-	switch (pdev->device) {
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB0:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB1:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB2:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB3:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB4:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB5:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB6:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB7:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB8:
-	case PCI_DEVICE_ID_INTEL_IOAT_SNB9:
-		return true;
-	default:
-		return false;
-	}
-}
-
-static bool is_ivb_ioat(struct pci_dev *pdev)
-{
-	switch (pdev->device) {
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB0:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB1:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB2:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB3:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB4:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB5:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB6:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB7:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB8:
-	case PCI_DEVICE_ID_INTEL_IOAT_IVB9:
-		return true;
-	default:
-		return false;
-	}
-
-}
-
-static bool is_hsw_ioat(struct pci_dev *pdev)
-{
-	switch (pdev->device) {
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW0:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW1:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW2:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW3:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW4:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW5:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW6:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW7:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW8:
-	case PCI_DEVICE_ID_INTEL_IOAT_HSW9:
-		return true;
-	default:
-		return false;
+	err = ioat2_reset_sync(chan, msecs_to_jiffies(200));
+	if (err) {
+		dev_err(&pdev->dev, "Failed to reset!\n");
+		return err;
 	}
 
-}
+	if (device->irq_mode != IOAT_NOIRQ && is_bwd_ioat(pdev))
+		err = ioat3_irq_reinit(device);
 
-static bool is_xeon_cb32(struct pci_dev *pdev)
-{
-	return is_jf_ioat(pdev) || is_snb_ioat(pdev) || is_ivb_ioat(pdev) ||
-		is_hsw_ioat(pdev);
+	return err;
 }
 
 int ioat3_dma_probe(struct ioatdma_device *device, int dca)