On 2/25/2025 3:24 PM, Lukas Wunner wrote:
On Tue, Feb 25, 2025 at 03:04:04PM +0530, Krishna Chaitanya Chundru wrote:
Introduce a common API to check if the PCIe link is active, replacing
duplicate code in multiple locations.
[...]
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -234,18 +234,7 @@ static void pcie_write_cmd_nowait(struct controller *ctrl, u16 cmd, u16 mask)
*/
int pciehp_check_link_active(struct controller *ctrl)
{
- struct pci_dev *pdev = ctrl_dev(ctrl);
- u16 lnk_status;
- int ret;
-
- ret = pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
- if (ret == PCIBIOS_DEVICE_NOT_FOUND || PCI_POSSIBLE_ERROR(lnk_status))
- return -ENODEV;
-
- ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
- ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
-
- return ret;
+ return pcie_is_link_active(ctrl_dev(ctrl));
}
Please replace all call sites of pciehp_check_link_active() with a call
to the new function.
ack
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4923,8 +4922,7 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type)
if (!dev->link_active_reporting)
return -ENOTTY;
- pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &status);
- if (!(status & PCI_EXP_LNKSTA_DLLLA))
+ if (pcie_is_link_active(dev))
return -ENOTTY;
Missing negation.
ack
+/**
+ * pcie_is_link_active() - Checks if the link is active or not
+ * @pdev: PCI device to query
+ *
+ * Check whether the link is active or not.
+ *
+ * If the config read returns error then return -ENODEV.
+ */
+int pcie_is_link_active(struct pci_dev *pdev)
Why not return bool?
pciehp_check_link_active is expecting int to make sure this new function
not disturbing the hotplug driver I added return type as int, I can
change it to bool if it fine with hotplug drivers.
I don't quite like the function name because in English the correct word
order is subject - predicate - object, i.e. pcie_link_is_active() or
even shorter, pcie_link_active().
ack
@@ -2094,6 +2095,10 @@ pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
{
return -ENOSPC;
}
+
+static inline int pcie_is_link_active(struct pci_dev *dev)
+{ return -ENODEV; }
+
#endif /* CONFIG_PCI */
Is the empty inline really necessary? What breaks if you leave it out?
ack I will remove it.
- Krishna Chaitanya.
Thanks,
Lukas
