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Michael Strauss
791897f5c7
[WHY] These fields are read for the explicit purpose of detecting embedded LTTPRs (i.e. between host ASIC and the user-facing port), and thus need to calculate the correct DPCD address offset based on LTTPR count to target the appropriate LTTPR's DPCD register space with these queries. [HOW] Cascaded LTTPRs in a link each snoop and increment LTTPR count when queried via DPCD read, so an LTTPR embedded in a source device (e.g. USB4 port on a laptop) will always be addressible using the max LTTPR count seen by the host. Therefore we simply need to use a recently added helper function to calculate the correct DPCD address to target potentially embedded LTTPRs based on the received LTTPR count. Cc: Mario Limonciello <mario.limonciello@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Michael Strauss <michael.strauss@amd.com> Signed-off-by: Alex Hung <alex.hung@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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 reStructuredText 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.