diff options
| author | Stefan Mätje <stefan.maetje@esd.eu> | 2019-03-29 18:07:35 +0100 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2019-04-06 09:25:47 -0500 |
| commit | 4ec73791a64bab25cabf16a6067ee478692e506d (patch) | |
| tree | 0ef29a9ccbd480436332dd50bfbcdf60667dc008 /include | |
| parent | 86fa6a344209d9414ea962b1f1ac6ade9dd7563a (diff) | |
PCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratum
Due to an erratum in some Pericom PCIe-to-PCI bridges in reverse mode
(conventional PCI on primary side, PCIe on downstream side), the Retrain
Link bit needs to be cleared manually to allow the link training to
complete successfully.
If it is not cleared manually, the link training is continuously restarted
and no devices below the PCI-to-PCIe bridge can be accessed. That means
drivers for devices below the bridge will be loaded but won't work and may
even crash because the driver is only reading 0xffff.
See the Pericom Errata Sheet PI7C9X111SLB_errata_rev1.2_102711.pdf for
details. Devices known as affected so far are: PI7C9X110, PI7C9X111SL,
PI7C9X130.
Add a new flag, clear_retrain_link, in struct pci_dev. Quirks for affected
devices set this bit.
Note that pcie_retrain_link() lives in aspm.c because that's currently the
only place we use it, but this erratum is not specific to ASPM, and we may
retrain links for other reasons in the future.
Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
[bhelgaas: apply regardless of CONFIG_PCIEASPM]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
CC: stable@vger.kernel.org
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/pci.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/pci.h b/include/linux/pci.h index 77448215ef5b..2c056a7a728a 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -348,6 +348,8 @@ struct pci_dev { unsigned int hotplug_user_indicators:1; /* SlotCtl indicators controlled exclusively by user sysfs */ + unsigned int clear_retrain_link:1; /* Need to clear Retrain Link + bit manually */ unsigned int d3_delay; /* D3->D0 transition time in ms */ unsigned int d3cold_delay; /* D3cold->D0 transition time in ms */ |