bd1b8041c2
commit 91e8b74fe6381e083f8aa55217bb0562785ab398 upstream. CRC errors (code -84 EILSEQ) have been observed for some SanDisk Ultra A1 cards when running at 50MHz. Waveform analysis suggest that the level shifters that are used on the RK3399-Q7 module for voltage translation between 3.0 and 3.3V don't handle clock rates at or above 48MHz properly. Back off to 40MHz for some safety margin. Cc: stable@vger.kernel.org Fixes: 60fd9f72ce8a ("arm64: dts: rockchip: add Haikou baseboard with RK3399-Q7 SoM") Signed-off-by: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com> Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com> Link: https://lore.kernel.org/r/20221019-upstream-puma-sd-40mhz-v1-0-754a76421518@theobroma-systems.com Signed-off-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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.