PCI: Retry BARs restoration for Type 0 headers only (a6cb9ee7) · Commits · 戴 / test

Some shortcomings introduced into pci_restore_state() by commit ("PCI: check for pci bar restore completion and retry") have been fixed by recent commit ("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 for all header types except for Type 0. Tested-by:

Mikko Vinni <mmvinni@yahoo.com> Signed-off-by:

Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

drivers/pci/pci.c

+15 −9

Original line number	Diff line number	Diff line
		@@ -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);

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