It will make sense to store the pcie_devcap2 value in the pci_dev structure instead of reading Device Capabilities 2 Register multiple times. Get the pcie_devcap2 value set_pcie_port_type(), then use cached pcie_devcap2 in the needed place. Signed-off-by: Dongdong Liu <liudongdong3@xxxxxxxxxx> --- drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c | 4 +--- drivers/pci/pci.c | 9 ++++----- drivers/pci/probe.c | 10 ++++------ include/linux/pci.h | 2 ++ 4 files changed, 11 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c index 1f601de..06d24c6 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c @@ -6303,7 +6303,6 @@ static int cxgb4_iov_configure(struct pci_dev *pdev, int num_vfs) struct pci_dev *pbridge; struct port_info *pi; char name[IFNAMSIZ]; - u32 devcap2; u16 flags; /* If we want to instantiate Virtual Functions, then our @@ -6313,10 +6312,9 @@ static int cxgb4_iov_configure(struct pci_dev *pdev, int num_vfs) */ pbridge = pdev->bus->self; pcie_capability_read_word(pbridge, PCI_EXP_FLAGS, &flags); - pcie_capability_read_dword(pbridge, PCI_EXP_DEVCAP2, &devcap2); if ((flags & PCI_EXP_FLAGS_VERS) < 2 || - !(devcap2 & PCI_EXP_DEVCAP2_ARI)) { + !(pbridge->pcie_devcap2 & PCI_EXP_DEVCAP2_ARI)) { /* Our parent bridge does not support ARI so issue a * warning and skip instantiating the VFs. They * won't be reachable. diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 68ccd77..e3cd2f4 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3690,7 +3690,7 @@ int pci_enable_atomic_ops_to_root(struct pci_dev *dev, u32 cap_mask) { struct pci_bus *bus = dev->bus; struct pci_dev *bridge; - u32 cap, ctl2; + u32 ctl2; if (!pci_is_pcie(dev)) return -EINVAL; @@ -3714,19 +3714,18 @@ int pci_enable_atomic_ops_to_root(struct pci_dev *dev, u32 cap_mask) while (bus->parent) { bridge = bus->self; - pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap); - switch (pci_pcie_type(bridge)) { /* Ensure switch ports support AtomicOp routing */ case PCI_EXP_TYPE_UPSTREAM: case PCI_EXP_TYPE_DOWNSTREAM: - if (!(cap & PCI_EXP_DEVCAP2_ATOMIC_ROUTE)) + if (!(bridge->pcie_devcap2 & + PCI_EXP_DEVCAP2_ATOMIC_ROUTE)) return -EINVAL; break; /* Ensure root port supports all the sizes we care about */ case PCI_EXP_TYPE_ROOT_PORT: - if ((cap & cap_mask) != cap_mask) + if ((bridge->pcie_devcap2 & cap_mask) != cap_mask) return -EINVAL; break; } diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 76ddc89..0208865 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1500,6 +1500,7 @@ void set_pcie_port_type(struct pci_dev *pdev) pdev->pcie_flags_reg = reg16; pci_read_config_dword(pdev, pos + PCI_EXP_DEVCAP, &pdev->pcie_devcap); pdev->pcie_mpss = pdev->pcie_devcap & PCI_EXP_DEVCAP_PAYLOAD; + pci_read_config_dword(pdev, pos + PCI_EXP_DEVCAP2, &pdev->pcie_devcap2); parent = pci_upstream_bridge(pdev); if (!parent) @@ -2094,7 +2095,7 @@ static void pci_configure_ltr(struct pci_dev *dev) #ifdef CONFIG_PCIEASPM struct pci_host_bridge *host = pci_find_host_bridge(dev->bus); struct pci_dev *bridge; - u32 cap, ctl; + u32 ctl; if (!pci_is_pcie(dev)) return; @@ -2102,8 +2103,7 @@ static void pci_configure_ltr(struct pci_dev *dev) /* Read L1 PM substate capabilities */ dev->l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS); - pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap); - if (!(cap & PCI_EXP_DEVCAP2_LTR)) + if (!(dev->pcie_devcap2 & PCI_EXP_DEVCAP2_LTR)) return; pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl); @@ -2143,13 +2143,11 @@ static void pci_configure_eetlp_prefix(struct pci_dev *dev) #ifdef CONFIG_PCI_PASID struct pci_dev *bridge; int pcie_type; - u32 cap; if (!pci_is_pcie(dev)) return; - pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap); - if (!(cap & PCI_EXP_DEVCAP2_EE_PREFIX)) + if (!(dev->pcie_devcap2 & PCI_EXP_DEVCAP2_EE_PREFIX)) return; pcie_type = pci_pcie_type(dev); diff --git a/include/linux/pci.h b/include/linux/pci.h index 0674161..de1fc24 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -341,6 +341,8 @@ struct pci_dev { u8 pin; /* Interrupt pin this device uses */ u16 pcie_flags_reg; /* Cached PCIe Capabilities Register */ u32 pcie_devcap; /* Cached Device Capabilities Register */ + u32 pcie_devcap2; /* Cached Device Capabilities 2 + Register */ unsigned long *dma_alias_mask;/* Mask of enabled devfn aliases */ struct pci_driver *driver; /* Driver bound to this device */ -- 2.7.4