[PATCH v9 01/14] PCI: pciehp: Rely on `link_active_reporting'

Maciej W. Rozycki
2023-06-11T17:19:25Z

Use `link_active_reporting' to determine whether Data Link Layer Link
Active Reporting is available rather than re-retrieving the capability.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
---
NB this has been compile-tested only with PPC64LE and x86-64
configurations.

No change from v8.

Changes from v7:

- Add Reviewed-by: tag by Lukas Wunner.

- Reorder from 6/7.

No change from v6.

New change in v6.
---
drivers/pci/hotplug/pciehp_hpc.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

linux-pcie-link-active-reporting-hpc.diff
Index: linux-macro/drivers/pci/hotplug/pciehp_hpc.c
===================================================================
--- linux-macro.orig/drivers/pci/hotplug/pciehp_hpc.c
+++ linux-macro/drivers/pci/hotplug/pciehp_hpc.c
@@ -984,7 +984,7 @@ static inline int pcie_hotplug_depth(str
struct controller *pcie_init(struct pcie_device *dev)
{
struct controller *ctrl;
- u32 slot_cap, slot_cap2, link_cap;
+ u32 slot_cap, slot_cap2;
u8 poweron;
struct pci_dev *pdev = dev->port;
struct pci_bus *subordinate = pdev->subordinate;
@@ -1030,9 +1030,6 @@ struct controller *pcie_init(struct pcie
if (dmi_first_match(inband_presence_disabled_dmi_table))
ctrl->inband_presence_disabled = 1;

- /* Check if Data Link Layer Link Active Reporting is implemented */
- pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
-
/* Clear all remaining event bits in Slot Status register. */
pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
@@ -1051,7 +1048,7 @@ struct controller *pcie_init(struct pcie
FLAG(slot_cap, PCI_EXP_SLTCAP_EIP),
FLAG(slot_cap, PCI_EXP_SLTCAP_NCCS),
FLAG(slot_cap2, PCI_EXP_SLTCAP2_IBPD),
- FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC),
+ FLAG(pdev->link_active_reporting, true),
pdev->broken_cmd_compl ? " (with Cmd Compl erratum)" : "");

/*