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path: root/drivers/pci/pcie/aspm.c
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Diffstat (limited to 'drivers/pci/pcie/aspm.c')
-rw-r--r--drivers/pci/pcie/aspm.c20
1 files changed, 9 insertions, 11 deletions
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index e0bc90597dca..29fcb0689a91 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -108,9 +108,6 @@ void pci_save_aspm_l1ss_state(struct pci_dev *pdev)
pci_read_config_dword(pdev, pdev->l1ss + PCI_L1SS_CTL2, cap++);
pci_read_config_dword(pdev, pdev->l1ss + PCI_L1SS_CTL1, cap++);
- if (parent->state_saved)
- return;
-
/*
* Save parent's L1 substate configuration so we have it for
* pci_restore_aspm_l1ss_state(pdev) to restore.
@@ -1273,16 +1270,16 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev)
parent_link = link->parent;
/*
- * link->downstream is a pointer to the pci_dev of function 0. If
- * we remove that function, the pci_dev is about to be deallocated,
- * so we can't use link->downstream again. Free the link state to
- * avoid this.
+ * Free the parent link state, no later than function 0 (i.e.
+ * link->downstream) being removed.
*
- * If we're removing a non-0 function, it's possible we could
- * retain the link state, but PCIe r6.0, sec 7.5.3.7, recommends
- * programming the same ASPM Control value for all functions of
- * multi-function devices, so disable ASPM for all of them.
+ * Do not free the link state any earlier. If function 0 is a
+ * switch upstream port, this link state is parent_link to all
+ * subordinate ones.
*/
+ if (pdev != link->downstream)
+ goto out;
+
pcie_config_aspm_link(link, 0);
list_del(&link->sibling);
free_link_state(link);
@@ -1293,6 +1290,7 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev)
pcie_config_aspm_path(parent_link);
}
+ out:
mutex_unlock(&aspm_lock);
up_read(&pci_bus_sem);
}