From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Jiang Liu To: Bjorn Helgaas , Don Dutile Cc: Yijing Wang , Yinghai Lu , Taku Izumi , "Rafael J . Wysocki" , Kenji Kaneshige , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Jiang Liu Subject: [RFC PATCH v2 01/32] PCI: add pcie_flags_reg into struct pci_dev to cache PCIe capabilities register Date: Wed, 25 Jul 2012 00:31:13 +0800 Message-Id: <1343147504-25891-2-git-send-email-jiang.liu@huawei.com> In-Reply-To: <1343147504-25891-1-git-send-email-jiang.liu@huawei.com> References: <1343147504-25891-1-git-send-email-jiang.liu@huawei.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Yijing Wang From: Yijing Wang Since PCI Express Capabilities Register is read only, cache its value into struct pci_dev to avoid repeatedly calling pci_read_config_*(). Signed-off-by: Yijing Wang Signed-off-by: Jiang Liu --- drivers/pci/probe.c | 1 + include/linux/pci.h | 10 ++++++++++ 2 files changed, 11 insertions(+) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 6c143b4..6fd58df 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -929,6 +929,7 @@ void set_pcie_port_type(struct pci_dev *pdev) pdev->is_pcie = 1; pdev->pcie_cap = pos; pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16); + pdev->pcie_flags_reg = reg16; pdev->pcie_type = (reg16 & PCI_EXP_FLAGS_TYPE) >> 4; pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16); pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD; diff --git a/include/linux/pci.h b/include/linux/pci.h index 5faa831..95662b2 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -258,6 +258,7 @@ struct pci_dev { u8 pcie_mpss:3; /* PCI-E Max Payload Size Supported */ u8 rom_base_reg; /* which config register controls the ROM */ u8 pin; /* which interrupt pin this device uses */ + u16 pcie_flags_reg; /* cached PCI-E Capabilities Register */ struct pci_driver *driver; /* which driver has allocated this device */ u64 dma_mask; /* Mask of the bits of bus address this @@ -1650,6 +1651,15 @@ static inline bool pci_is_pcie(struct pci_dev *dev) return !!pci_pcie_cap(dev); } +/** + * pci_pcie_type - get the PCIe device/port type + * @dev: PCI device + */ +static inline int pci_pcie_type(const struct pci_dev *dev) +{ + return (dev->pcie_flags_reg & PCI_EXP_FLAGS_TYPE) >> 4; +} + void pci_request_acs(void); bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags); bool pci_acs_path_enabled(struct pci_dev *start, -- 1.7.9.5