Merge branch 'pci/reset'

- Add pci_reset_bus_function() Secondary Bus Reset interface (Raphael
  Norwitz)

- Work around Huawei Intelligent NIC VF FLR erratum (Chiqijun)

* pci/reset:
  PCI: Work around Huawei Intelligent NIC VF FLR erratum
  PCI: Add pci_reset_bus_function() Secondary Bus Reset interface

1 files changed, 65 insertions, 0 deletions

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 0dde9c5259f2..8a4f56eebcef 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3912,6 +3912,69 @@ static int delay_250ms_after_flr(struct pci_dev *dev, int probe)
 	return 0;
 }
 
+#define PCI_DEVICE_ID_HINIC_VF      0x375E
+#define HINIC_VF_FLR_TYPE           0x1000
+#define HINIC_VF_FLR_CAP_BIT        (1UL << 30)
+#define HINIC_VF_OP                 0xE80
+#define HINIC_VF_FLR_PROC_BIT       (1UL << 18)
+#define HINIC_OPERATION_TIMEOUT     15000	/* 15 seconds */
+
+/* Device-specific reset method for Huawei Intelligent NIC virtual functions */
+static int reset_hinic_vf_dev(struct pci_dev *pdev, int probe)
+{
+	unsigned long timeout;
+	void __iomem *bar;
+	u32 val;
+
+	if (probe)
+		return 0;
+
+	bar = pci_iomap(pdev, 0, 0);
+	if (!bar)
+		return -ENOTTY;
+
+	/* Get and check firmware capabilities */
+	val = ioread32be(bar + HINIC_VF_FLR_TYPE);
+	if (!(val & HINIC_VF_FLR_CAP_BIT)) {
+		pci_iounmap(pdev, bar);
+		return -ENOTTY;
+	}
+
+	/* Set HINIC_VF_FLR_PROC_BIT for the start of FLR */
+	val = ioread32be(bar + HINIC_VF_OP);
+	val = val | HINIC_VF_FLR_PROC_BIT;
+	iowrite32be(val, bar + HINIC_VF_OP);
+
+	pcie_flr(pdev);
+
+	/*
+	 * The device must recapture its Bus and Device Numbers after FLR
+	 * in order generate Completions.  Issue a config write to let the
+	 * device capture this information.
+	 */
+	pci_write_config_word(pdev, PCI_VENDOR_ID, 0);
+
+	/* Firmware clears HINIC_VF_FLR_PROC_BIT when reset is complete */
+	timeout = jiffies + msecs_to_jiffies(HINIC_OPERATION_TIMEOUT);
+	do {
+		val = ioread32be(bar + HINIC_VF_OP);
+		if (!(val & HINIC_VF_FLR_PROC_BIT))
+			goto reset_complete;
+		msleep(20);
+	} while (time_before(jiffies, timeout));
+
+	val = ioread32be(bar + HINIC_VF_OP);
+	if (!(val & HINIC_VF_FLR_PROC_BIT))
+		goto reset_complete;
+
+	pci_warn(pdev, "Reset dev timeout, FLR ack reg: %#010x\n", val);
+
+reset_complete:
+	pci_iounmap(pdev, bar);
+
+	return 0;
+}
+
 static const struct pci_dev_reset_methods pci_dev_reset_methods[] = {
 	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82599_SFP_VF,
 		 reset_intel_82599_sfp_virtfn },
@@ -3924,6 +3987,8 @@ static const struct pci_dev_reset_methods pci_dev_reset_methods[] = {
 	{ PCI_VENDOR_ID_INTEL, 0x0a54, delay_250ms_after_flr },
 	{ PCI_VENDOR_ID_CHELSIO, PCI_ANY_ID,
 		reset_chelsio_generic_dev },
+	{ PCI_VENDOR_ID_HUAWEI, PCI_DEVICE_ID_HINIC_VF,
+		reset_hinic_vf_dev },
 	{ 0 }
 };