From 1ca887970a3971a22e4875b7c6ad5ae3ce49f61a Mon Sep 17 00:00:00 2001 From: Sheng Yang Date: Tue, 11 Nov 2008 17:17:48 +0800 Subject: [PATCH] PCI: Extend pci_reset_function() to support PCI Advanced Features Some PCI devices implement PCI Advanced Features, which means they support Function Level Reset(FLR). Implement support for that in pci_reset_function. Signed-off-by: Sheng Yang Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 62978f644a92..3c2fa2fdc9cd 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1789,6 +1789,43 @@ static int __pcie_flr(struct pci_dev *dev, int probe) return 0; } +static int __pci_af_flr(struct pci_dev *dev, int probe) +{ + int cappos = pci_find_capability(dev, PCI_CAP_ID_AF); + u8 status; + u8 cap; + + if (!cappos) + return -ENOTTY; + pci_read_config_byte(dev, cappos + PCI_AF_CAP, &cap); + if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR)) + return -ENOTTY; + + if (probe) + return 0; + + pci_block_user_cfg_access(dev); + + /* Wait for Transaction Pending bit clean */ + msleep(100); + pci_read_config_byte(dev, cappos + PCI_AF_STATUS, &status); + if (status & PCI_AF_STATUS_TP) { + dev_info(&dev->dev, "Busy after 100ms while trying to" + " reset; sleeping for 1 second\n"); + ssleep(1); + pci_read_config_byte(dev, + cappos + PCI_AF_STATUS, &status); + if (status & PCI_AF_STATUS_TP) + dev_info(&dev->dev, "Still busy after 1s; " + "proceeding with reset anyway\n"); + } + pci_write_config_byte(dev, cappos + PCI_AF_CTRL, PCI_AF_CTRL_FLR); + mdelay(100); + + pci_unblock_user_cfg_access(dev); + return 0; +} + static int __pci_reset_function(struct pci_dev *pdev, int probe) { int res; @@ -1797,6 +1834,10 @@ static int __pci_reset_function(struct pci_dev *pdev, int probe) if (res != -ENOTTY) return res; + res = __pci_af_flr(pdev, probe); + if (res != -ENOTTY) + return res; + return res; } -- 2.20.1