e10f480902
This change will allow platform designers better control over signal integrity by allowing them to tune the HS200 and HS400 driver strengths. The driver strength was previously hard coded to A to solve boot problems with certain platforms. This driver strength does not universally apply to all platforms so we need a knob to adjust it. All older platforms currently have the SDR104 preset hard coded to A in the firmware. This means that switching from the hard coded value in the kernel to reading the SDR104 preset is a no-op for these platforms. Newer platforms will have properly set presets. So this change will support both new and old platforms. Signed-off-by: Raul E Rangel <rrangel@chromium.org> Signed-off-by: Victor Ding <victording@google.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Link: https://lore.kernel.org/r/20201027084612.528301-1-victording@google.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.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.