From a6cb9ee7cabe68002c3f2ab07224ea27d2617cf1 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 16 Apr 2012 23:07:50 +0200 Subject: [PATCH] PCI: Retry BARs restoration for Type 0 headers only Some shortcomings introduced into pci_restore_state() by commit 26f41062f28d ("PCI: check for pci bar restore completion and retry") have been fixed by recent commit ebfc5b802fa76 ("PCI: Fix regression in pci_restore_state(), v3"), but that commit treats all PCI devices as those with Type 0 configuration headers. That is not entirely correct, because Type 1 and Type 2 headers have different layouts. In particular, the area occupied by BARs in Type 0 config headers contains the secondary status register in Type 1 ones and it doesn't make sense to retry the restoration of that register even if the value read back from it after a write is not the same as the written one (it very well may be different). For this reason, make pci_restore_state() only retry the restoration of BARs for Type 0 config headers. This effectively makes it behave as before commit 26f41062f28d for all header types except for Type 0. Tested-by: Mikko Vinni Signed-off-by: Rafael J. Wysocki Signed-off-by: Linus Torvalds --- drivers/pci/pci.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index d20f1334792b..111569ccab43 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -991,8 +991,8 @@ static void pci_restore_config_dword(struct pci_dev *pdev, int offset, } } -static void pci_restore_config_space(struct pci_dev *pdev, int start, int end, - int retry) +static void pci_restore_config_space_range(struct pci_dev *pdev, + int start, int end, int retry) { int index; @@ -1002,6 +1002,18 @@ static void pci_restore_config_space(struct pci_dev *pdev, int start, int end, retry); } +static void pci_restore_config_space(struct pci_dev *pdev) +{ + if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) { + pci_restore_config_space_range(pdev, 10, 15, 0); + /* Restore BARs before the command register. */ + pci_restore_config_space_range(pdev, 4, 9, 10); + pci_restore_config_space_range(pdev, 0, 3, 0); + } else { + pci_restore_config_space_range(pdev, 0, 15, 0); + } +} + /** * pci_restore_state - Restore the saved state of a PCI device * @dev: - PCI device that we're dealing with @@ -1015,13 +1027,7 @@ void pci_restore_state(struct pci_dev *dev) pci_restore_pcie_state(dev); pci_restore_ats_state(dev); - pci_restore_config_space(dev, 10, 15, 0); - /* - * The Base Address register should be programmed before the command - * register(s) - */ - pci_restore_config_space(dev, 4, 9, 10); - pci_restore_config_space(dev, 0, 3, 0); + pci_restore_config_space(dev); pci_restore_pcix_state(dev); pci_restore_msi_state(dev); -- 2.39.5