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path: root/drivers/pci/pci.c
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Diffstat (limited to 'drivers/pci/pci.c')
-rw-r--r--drivers/pci/pci.c49
1 files changed, 37 insertions, 12 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 5ede93222bc1..578bf0d3ec3c 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -65,6 +65,13 @@ struct pci_pme_device {
#define PME_TIMEOUT 1000 /* How long between PME checks */
/*
+ * Following exit from Conventional Reset, devices must be ready within 1 sec
+ * (PCIe r6.0 sec 6.6.1). A D3cold to D0 transition implies a Conventional
+ * Reset (PCIe r6.0 sec 5.8).
+ */
+#define PCI_RESET_WAIT 1000 /* msec */
+
+/*
* Devices may extend the 1 sec period through Request Retry Status
* completions (PCIe r6.0 sec 2.3.1). The spec does not provide an upper
* limit, but 60 sec ought to be enough for any device to become
@@ -5011,11 +5018,9 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type)
*
* However, 100 ms is the minimum and the PCIe spec says the
* software must allow at least 1s before it can determine that the
- * device that did not respond is a broken device. There is
- * evidence that 100 ms is not always enough, for example certain
- * Titan Ridge xHCI controller does not always respond to
- * configuration requests if we only wait for 100 ms (see
- * https://bugzilla.kernel.org/show_bug.cgi?id=203885).
+ * device that did not respond is a broken device. Also device can
+ * take longer than that to respond if it indicates so through Request
+ * Retry Status completions.
*
* Therefore we wait for 100 ms and check for the device presence
* until the timeout expires.
@@ -5024,16 +5029,36 @@ int pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, char *reset_type)
return 0;
if (pcie_get_speed_cap(dev) <= PCIE_SPEED_5_0GT) {
+ u16 status;
+
pci_dbg(dev, "waiting %d ms for downstream link\n", delay);
msleep(delay);
- } else {
- pci_dbg(dev, "waiting %d ms for downstream link, after activation\n",
- delay);
- if (!pcie_wait_for_link_delay(dev, true, delay)) {
- /* Did not train, no need to wait any further */
- pci_info(dev, "Data Link Layer Link Active not set in 1000 msec\n");
+
+ if (!pci_dev_wait(child, reset_type, PCI_RESET_WAIT - delay))
+ return 0;
+
+ /*
+ * If the port supports active link reporting we now check
+ * whether the link is active and if not bail out early with
+ * the assumption that the device is not present anymore.
+ */
+ if (!dev->link_active_reporting)
return -ENOTTY;
- }
+
+ pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &status);
+ if (!(status & PCI_EXP_LNKSTA_DLLLA))
+ return -ENOTTY;
+
+ return pci_dev_wait(child, reset_type,
+ PCIE_RESET_READY_POLL_MS - PCI_RESET_WAIT);
+ }
+
+ pci_dbg(dev, "waiting %d ms for downstream link, after activation\n",
+ delay);
+ if (!pcie_wait_for_link_delay(dev, true, delay)) {
+ /* Did not train, no need to wait any further */
+ pci_info(dev, "Data Link Layer Link Active not set in 1000 msec\n");
+ return -ENOTTY;
}
return pci_dev_wait(child, reset_type,