From 157e876ffe0b28821a0d82d8ac944fe7363bbe87 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Tue, 17 Dec 2013 16:43:39 -0700 Subject: [PATCH] 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 Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 54 ++++++++++++++++++++++++++++++----------------------- include/linux/pci.h | 1 + 2 files changed, 32 insertions(+), 23 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 33120d1..bb257b9 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -431,6 +431,32 @@ pci_find_parent_resource(const struct pci_dev *dev, struct resource *res) } /** + * 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 1084a15..211ce43 100644 --- 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); -- 2.7.4