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-rw-r--r--drivers/pci/pci.h1
-rw-r--r--drivers/pci/probe.c14
-rw-r--r--drivers/pci/search.c34
3 files changed, 49 insertions, 0 deletions
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 6fda33d..fc87e14 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 5db6b66..463a5a9 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, &reg16);
+ 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 c6e79d0..b001b59 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)
{