diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/pci/pci.h | 1 | ||||
| -rw-r--r-- | drivers/pci/probe.c | 14 | ||||
| -rw-r--r-- | drivers/pci/search.c | 34 |
3 files changed, 49 insertions, 0 deletions
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 6fda33de84e8..fc87e14b50de 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -90,3 +90,4 @@ pci_match_one_device(const struct pci_device_id *id, const struct pci_dev *dev) return NULL; } +struct pci_dev *pci_find_upstream_pcie_bridge(struct pci_dev *pdev); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 5db6b6690b59..463a5a9d583d 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -837,6 +837,19 @@ static void pci_release_dev(struct device *dev) kfree(pci_dev); } +static void set_pcie_port_type(struct pci_dev *pdev) +{ + int pos; + u16 reg16; + + pos = pci_find_capability(pdev, PCI_CAP_ID_EXP); + if (!pos) + return; + pdev->is_pcie = 1; + pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16); + pdev->pcie_type = (reg16 & PCI_EXP_FLAGS_TYPE) >> 4; +} + /** * pci_cfg_space_size - get the configuration space size of the PCI device. * @dev: PCI device @@ -951,6 +964,7 @@ pci_scan_device(struct pci_bus *bus, int devfn) dev->device = (l >> 16) & 0xffff; dev->cfg_size = pci_cfg_space_size(dev); dev->error_state = pci_channel_io_normal; + set_pcie_port_type(dev); /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer) set this higher, assuming the system even supports it. */ diff --git a/drivers/pci/search.c b/drivers/pci/search.c index c6e79d01ce3d..b001b5922e33 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -14,6 +14,40 @@ #include "pci.h" DECLARE_RWSEM(pci_bus_sem); +/* + * find the upstream PCIE-to-PCI bridge of a PCI device + * if the device is PCIE, return NULL + * if the device isn't connected to a PCIE bridge (that is its parent is a + * legacy PCI bridge and the bridge is directly connected to bus 0), return its + * parent + */ +struct pci_dev * +pci_find_upstream_pcie_bridge(struct pci_dev *pdev) +{ + struct pci_dev *tmp = NULL; + + if (pdev->is_pcie) + return NULL; + while (1) { + if (!pdev->bus->self) + break; + pdev = pdev->bus->self; + /* a p2p bridge */ + if (!pdev->is_pcie) { + tmp = pdev; + continue; + } + /* PCI device should connect to a PCIE bridge */ + if (pdev->pcie_type != PCI_EXP_TYPE_PCI_BRIDGE) { + /* Busted hardware? */ + WARN_ON_ONCE(1); + return NULL; + } + return pdev; + } + + return tmp; +} static struct pci_bus *pci_do_find_bus(struct pci_bus *bus, unsigned char busnr) { |