mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-03 10:02:20 -04:00
8ec7d60432
Update D0 <-> D3 sequence to correctly transition hardware and DSP core from and to D3. On top of that, set SHIM registers to their recommended defaults during D0 and D3 proceduces as HW does not reset registers for us. Connected to: [alsa-devel][BUG] bdw-rt5650 DSP boot timeout https://mailman.alsa-project.org/pipermail/alsa-devel/2019-July/153098.html Github issue ticket reference: https://github.com/thesofproject/linux/pull/1842 Tested on: - BDW-Y RVP with rt286 - SAMUS with rt5677 Proposed solution (both in July 2019 and on github): 'Revert "ASoC: Intel: Work around to fix HW d3 potential crash issue"' is NAKed as it only covers the problem up and actually brings back the undefined behavior: some registers (e.g.: APLLSE) are describing LPT offsets rather than WPT ones. In consequence, during power-transitions driver issues incorrect writes and leaves the regs of interest alone. Existing patch - the non-revert - does not resolve the HW D3 issue at all as it ignores the recommended sequence and does not initialize hardware registers as expected. And thus, leaving things as are is also unacceptable. Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com> Tested-by: Ross Zwisler <zwisler@google.com> Link: https://lore.kernel.org/r/20200330194520.13253-1-cezary.rojewski@intel.com Signed-off-by: Mark Brown <broonie@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.