mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-05 18:13:26 -04:00
e7e3975636
PCIe r6.0.1, sec 7.5.3.7, recommends setting the link control parameters,
then waiting for the Link Training bit to be clear before setting the
Retrain Link bit.
This avoids a race where the LTSSM may not use the updated parameters if it
is already in the midst of link training because of other normal link
activity.
Wait for the Link Training bit to be clear before toggling the Retrain Link
bit to ensure that the LTSSM uses the updated link control parameters.
[bhelgaas: commit log, return 0 (success)/-ETIMEDOUT instead of bool for
both pcie_wait_for_retrain() and the existing pcie_retrain_link()]
Suggested-by: Lukas Wunner <lukas@wunner.de>
Fixes: 7d715a6c1a ("PCI: add PCI Express ASPM support")
Link: https://lore.kernel.org/r/20230502083923.34562-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.