Commit 977509f7 authored Jan 02, 2017 by Bjorn Helgaas

PCI: Apply _HPX settings only to relevant devices

Previously we didn't check the type of device before trying to apply Type 1
(PCI-X) or Type 2 (PCIe) Setting Records from _HPX.

We don't support PCI-X Setting Records, so this was harmless, but the
warning was useless.

We do support PCIe Setting Records, and we didn't check whether a device
was PCIe before applying settings.  I don't think anything bad happened on
non-PCIe devices because pcie_capability_clear_and_set_word(),
pcie_cap_has_lnkctl(), etc., would fail before doing any harm.  But it's
ugly to depend on those internals.

Check the device type before attempting to apply Type 1 and Type 2 Setting
Records (Type 0 records are applicable to PCI, PCI-X, and PCIe devices).

A side benefit is that this prevents useless "not supported" warnings when
a BIOS supplies a Type 1 (PCI-X) Setting Record and we try to apply it to
every single device:

  pci 0000:00:00.0: PCI-X settings not supported

After this patch, we'll get the warning only when a BIOS supplies a Type 1
record and we have a PCI-X device to which it should be applied.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=187731


Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

parent 7ce7d89f

drivers/pci/probe.c

+13 −2

Original line number	Diff line number	Diff line
		@@ -1554,7 +1554,15 @@ static void program_hpp_type0(struct pci_dev dev, struct hpp_type0 hpp)

		static void program_hpp_type1(struct pci_dev dev, struct hpp_type1 hpp)
		{
		if (hpp)
		int pos;

		if (!hpp)
		return;

		pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
		if (!pos)
		return;

		dev_warn(&dev->dev, "PCI-X settings not supported\n");
		}

		@@ -1581,6 +1589,9 @@ static void program_hpp_type2(struct pci_dev dev, struct hpp_type2 hpp)
		if (!hpp)
		return;

		if (!pci_is_pcie(dev))
		return;

		if (hpp->revision > 1) {
		dev_warn(&dev->dev, "PCIe settings rev %d not supported\n",
		hpp->revision);

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