PCI: Add pci_wait_for_pending() (refactor pci_wait_for_pending_transaction())

We currently have two instance of this loop which waits for a pending bit
to clear in a status dword.  Generalize the function for future users.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 33120d15666895a2b48aec1c83f7b41f7b93c3be..bb257b975a8f795787d0552f85a06b3096ba5d57 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -430,6 +430,32 @@ pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
        return best;
 }
 
+/**
+ * pci_wait_for_pending - wait for @mask bit(s) to clear in status word @pos
+ * @dev: the PCI device to operate on
+ * @pos: config space offset of status word
+ * @mask: mask of bit(s) to care about in status word
+ *
+ * Return 1 when mask bit(s) in status word clear, 0 otherwise.
+ */
+int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask)
+{
+       int i;
+
+       /* Wait for Transaction Pending bit clean */
+       for (i = 0; i < 4; i++) {
+               u16 status;
+               if (i)
+                       msleep((1 << (i - 1)) * 100);
+
+               pci_read_config_word(dev, pos, &status);
+               if (!(status & mask))
+                       return 1;
+       }
+
+       return 0;
+}
+
 /**
  * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
  * @dev: PCI device to have its BARs restored
@@ -3204,20 +3230,10 @@ EXPORT_SYMBOL(pci_set_dma_seg_boundary);
  */
 int pci_wait_for_pending_transaction(struct pci_dev *dev)
 {
-       int i;
-       u16 status;
-
-       /* Wait for Transaction Pending bit clean */
-       for (i = 0; i < 4; i++) {
-               if (i)
-                       msleep((1 << (i - 1)) * 100);
-
-               pcie_capability_read_word(dev, PCI_EXP_DEVSTA, &status);
-               if (!(status & PCI_EXP_DEVSTA_TRPND))
-                       return 1;
-       }
+       if (!pci_is_pcie(dev))
+               return 1;
 
-       return 0;
+       return pci_wait_for_pending(dev, PCI_EXP_DEVSTA, PCI_EXP_DEVSTA_TRPND);
 }
 EXPORT_SYMBOL(pci_wait_for_pending_transaction);
 
@@ -3244,10 +3260,8 @@ static int pcie_flr(struct pci_dev *dev, int probe)
 
 static int pci_af_flr(struct pci_dev *dev, int probe)
 {
-       int i;
        int pos;
        u8 cap;
-       u8 status;
 
        pos = pci_find_capability(dev, PCI_CAP_ID_AF);
        if (!pos)
@@ -3261,14 +3275,8 @@ static int pci_af_flr(struct pci_dev *dev, int probe)
                return 0;
 
        /* Wait for Transaction Pending bit clean */
-       for (i = 0; i < 4; i++) {
-               if (i)
-                       msleep((1 << (i - 1)) * 100);
-
-               pci_read_config_byte(dev, pos + PCI_AF_STATUS, &status);
-               if (!(status & PCI_AF_STATUS_TP))
-                       goto clear;
-       }
+       if (pci_wait_for_pending(dev, PCI_AF_STATUS, PCI_AF_STATUS_TP))
+               goto clear;
 
        dev_err(&dev->dev, "transaction is not cleared; "
                        "proceeding with reset anyway\n");

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 1084a15175e04ff0bc715e3e429aab7027d279f8..211ce43ba48324b8568af7c5be3d3d8fa4107344 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -938,6 +938,7 @@ bool pci_check_and_unmask_intx(struct pci_dev *dev);
 void pci_msi_off(struct pci_dev *dev);
 int pci_set_dma_max_seg_size(struct pci_dev *dev, unsigned int size);
 int pci_set_dma_seg_boundary(struct pci_dev *dev, unsigned long mask);
+int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask);
 int pci_wait_for_pending_transaction(struct pci_dev *dev);
 int pcix_get_max_mmrbc(struct pci_dev *dev);
 int pcix_get_mmrbc(struct pci_dev *dev);