mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-29 08:12:41 -04:00
c8af5274c3
For all platforms that run haswell_crtc_enable, our spec tells us to configure the transcoder clocks and do link training before it tells us to set pipeconf and the other pipe/transcoder/plane registers. Starting from Icelake, we get machine hangs if we try to touch the pipe/transcoder registers without having the clocks configured and not having some chicken bits set. So this patch changes haswell_crtc_enable() to issue the calls at the appropriate order mandated by the spec. While setting the appropriate chicken bits would also work here, it's better if we actually program the hardware the way it is intended to be programmed. And the chicken bit also has some theoretical downsides that may or may not affect us. Also, correctly programming the hardware does not prevent us from setting the chicken bits in a later patch in case we decide to. v2: Don't forget link training (Ville). Cc: Arthur J Runyan <arthur.j.runyan@intel.com> Cc: James Ausmus <james.ausmus@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Reviewed-by: Manasi Navare <manasi.d.navare@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180502215851.30736-1-paulo.r.zanoni@intel.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 Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
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.