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Revision d2e3fce9ddafe689c6f7cb355f23560637e30b9d authored by Ville Syrjälä on 10 November 2020, 21:04:47 UTC, committed by Rodrigo Vivi on 19 November 2020, 06:52:25 UTC 
drm/i915: Handle max_bpc==16
 
EDID can declare the maximum supported bpc up to 16,
and apparently there are displays that do so. Currently
we assume 12 bpc is tha max. Fix the assumption and
toss in a MISSING_CASE() for any other value we don't
expect to see.

This fixes modesets with a display with EDID max bpc > 12.
Previously any modeset would just silently fail on platforms
that didn't otherwise limit this via the max_bpc property.
In particular we don't add the max_bpc property to HDMI
ports on gmch platforms, and thus we would see the raw
max_bpc coming from the EDID.

I suppose we could already adjust this to also allow 16bpc,
but seeing as no current platform supports that there is
little point.

Cc: stable@vger.kernel.org
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2632
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201110210447.27454-1-ville.syrjala@linux.intel.com
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
(cherry picked from commit 2ca5a7b85b0c2b97ef08afbd7799b022e29f192e)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
1 parent b5462cc
Raw File
vexpress.rst 
Kernel driver vexpress
======================

Supported systems:

  * ARM Ltd. Versatile Express platform

    Prefix: 'vexpress'

    Datasheets:

      * "Hardware Description" sections of the Technical Reference Manuals
	for the Versatile Express boards:

	- http://infocenter.arm.com/help/topic/com.arm.doc.subset.boards.express/index.html

      * Section "4.4.14. System Configuration registers" of the V2M-P1 TRM:

	- http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0447-/index.html

Author: Pawel Moll

Description
-----------

Versatile Express platform (http://www.arm.com/versatileexpress/) is a
reference & prototyping system for ARM Ltd. processors. It can be set up
from a wide range of boards, each of them containing (apart of the main
chip/FPGA) a number of microcontrollers responsible for platform
configuration and control. Theses microcontrollers can also monitor the
board and its environment by a number of internal and external sensors,
providing information about power lines voltages and currents, board
temperature and power usage. Some of them also calculate consumed energy
and provide a cumulative use counter.

The configuration devices are _not_ memory mapped and must be accessed
via a custom interface, abstracted by the "vexpress_config" API.

As these devices are non-discoverable, they must be described in a Device
Tree passed to the kernel. Details of the DT binding for them can be found
in Documentation/devicetree/bindings/hwmon/vexpress.txt.
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