[PATCH 5.4 045/168] PCI/PM: Add pcie_wait_for_link_delay()

From: Greg Kroah-Hartman
Date: Tue Apr 28 2020 - 14:36:54 EST


From: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

[ Upstream commit 4827d63891b6a839dac49c6ab62e61c4b011c4f2 ]

Add pcie_wait_for_link_delay(). Similar to pcie_wait_for_link() but allows
passing custom activation delay in milliseconds.

Link: https://lore.kernel.org/r/20191112091617.70282-2-mika.westerberg@xxxxxxxxxxxxxxx
Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/pci/pci.c | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 981ae16f935bc..94d6e120b4734 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4605,14 +4605,17 @@ static int pci_pm_reset(struct pci_dev *dev, int probe)

return pci_dev_wait(dev, "PM D3->D0", PCIE_RESET_READY_POLL_MS);
}
+
/**
- * pcie_wait_for_link - Wait until link is active or inactive
+ * pcie_wait_for_link_delay - Wait until link is active or inactive
* @pdev: Bridge device
* @active: waiting for active or inactive?
+ * @delay: Delay to wait after link has become active (in ms)
*
* Use this to wait till link becomes active or inactive.
*/
-bool pcie_wait_for_link(struct pci_dev *pdev, bool active)
+static bool pcie_wait_for_link_delay(struct pci_dev *pdev, bool active,
+ int delay)
{
int timeout = 1000;
bool ret;
@@ -4649,13 +4652,25 @@ bool pcie_wait_for_link(struct pci_dev *pdev, bool active)
timeout -= 10;
}
if (active && ret)
- msleep(100);
+ msleep(delay);
else if (ret != active)
pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n",
active ? "set" : "cleared");
return ret == active;
}

+/**
+ * pcie_wait_for_link - Wait until link is active or inactive
+ * @pdev: Bridge device
+ * @active: waiting for active or inactive?
+ *
+ * Use this to wait till link becomes active or inactive.
+ */
+bool pcie_wait_for_link(struct pci_dev *pdev, bool active)
+{
+ return pcie_wait_for_link_delay(pdev, active, 100);
+}
+
void pci_reset_secondary_bus(struct pci_dev *dev)
{
u16 ctrl;
--
2.20.1