This now fails unconditionally and will be always optimised away, but
provides for quirks to implement recovery for failed links detected in
device probing and device hot plug events.
Signed-off-by: Maciej W. Rozycki <ma...@orcam.me.uk>
---
New change in v9, factored out from 7/7:
- Rename `pcie_downstream_link_retrain' to `pcie_failed_link_retrain'.
- Add stub implementation in "pci.h".
---
drivers/pci/pci.c | 2 ++
drivers/pci/pci.h | 4 ++++
drivers/pci/probe.c | 2 ++
3 files changed, 8 insertions(+)
linux-pcie-failed-link-retrain.diff
Index: linux-macro/drivers/pci/pci.c
===================================================================
--- linux-macro.orig/drivers/pci/pci.c
+++ linux-macro/drivers/pci/pci.c
@@ -4912,6 +4912,8 @@ static bool pcie_wait_for_link_delay(str
if (active)
msleep(20);
ret = pcie_wait_for_link_status(pdev, false, active);
+ if (active && !ret)
+ ret = pcie_failed_link_retrain(pdev);
if (active && ret)
msleep(delay);
Index: linux-macro/drivers/pci/pci.h
===================================================================
--- linux-macro.orig/drivers/pci/pci.h
+++ linux-macro/drivers/pci/pci.h
@@ -554,6 +554,10 @@ static inline int pci_dev_specific_disab
return -ENOTTY;
}
#endif
+static inline bool pcie_failed_link_retrain(struct pci_dev *dev)
+{
+ return false;
+}
/* PCI error reporting and recovery */
pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
Index: linux-macro/drivers/pci/probe.c
===================================================================
--- linux-macro.orig/drivers/pci/probe.c
+++ linux-macro/drivers/pci/probe.c
@@ -2549,6 +2549,8 @@ void pci_device_add(struct pci_dev *dev,
dma_set_max_seg_size(&dev->dev, 65536);
dma_set_seg_boundary(&dev->dev, 0xffffffff);
+ pcie_failed_link_retrain(dev);
+
/* Fix up broken headers */
pci_fixup_device(pci_fixup_header, dev);
