Commit d3694d4f authored Aug 27, 2013 by Bjorn Helgaas

PCI: Allow PCIe Capability link-related register access for switches

Every PCIe device has a link, except Root Complex Integrated Endpoints
and Root Complex Event Collectors. Previously we didn't give access
to PCIe capability link-related registers for Upstream Ports, Downstream
Ports, and Bridges, so attempts to read PCI_EXP_LNKCTL incorrectly
returned zero. See PCIe spec r3.0, sec 7.8 and 1.3.2.3.

Reference: http://lkml.kernel.org/r/979A8436335E3744ADCD3A9F2A2B68A52AD136BE@SJEXCHMB10.corp.ad.broadcom.com

Reported-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-By: Jiang Liu <jiang.liu@huawei.com>

parent bd6fb762

drivers/pci/access.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -485,9 +485,13 @@ static inline bool pcie_cap_has_lnkctl(const struct pci_dev *dev)
		int type = pci_pcie_type(dev);

		return pcie_cap_version(dev) > 1 \|\|
		type == PCI_EXP_TYPE_ROOT_PORT \|\|
		type == PCI_EXP_TYPE_ENDPOINT \|\|
		type == PCI_EXP_TYPE_LEG_END;
		type == PCI_EXP_TYPE_LEG_END \|\|
		type == PCI_EXP_TYPE_ROOT_PORT \|\|
		type == PCI_EXP_TYPE_UPSTREAM \|\|
		type == PCI_EXP_TYPE_DOWNSTREAM \|\|
		type == PCI_EXP_TYPE_PCI_BRIDGE \|\|
		type == PCI_EXP_TYPE_PCIE_BRIDGE;
		}

		static inline bool pcie_cap_has_sltctl(const struct pci_dev *dev)